JP2006242232A - Electric exhaust valve and blood pressure meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric exhaust valve having simple and compact construction for exhibiting stable property independently of an attitude difference. <P>SOLUTION: The electric exhaust valve comprises a rod fixed iron core 12 having one longitudinal end face 12b to which a flow-out port 17 for exhausting air is opened, an exciting coil 13 arranged on the outer periphery of the fixed iron core for energizing the fixed iron core to be magnetized in the longitudinal direction, a movable iron piece 21 to be magnetically attracted from an initial position toward the end face of the fixed iron core to which the flow-out port is opened, when the fixed iron core is magnetized, a plate spring 20 for holding the movable iron piece being energized to the initial position, and a rubber valve 22 provided on the movable iron piece for adjusting the opening of the flow-out port depending on the position of the movable iron piece when magnetically attracted toward the end face of the fixed ion core against the energizing force of the plate spring. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electric exhaust valve that is particularly suitable for application to an exhaust device for a sphygmomanometer, and a sphygmomanometer that includes the electric exhaust valve.

  Some sphygmomanometers increase the pressure in the cuff zone to a predetermined value, and then gradually reduce the pressure, and measure the blood pressure value in this pressure reduction process. In such a sphygmomanometer, an electric exhaust valve is used to gradually reduce the pressure in the cuff belt.

  As a conventional example of an electric exhaust valve used in a sphygmomanometer, one described in Patent Document 1 is known. This electric exhaust valve is of a moving coil type and is configured as shown in FIG.

  In FIG. 12, 201 is a main body housing and 202 is a front housing. The front housing 202 that closes the front end opening of the main body housing 201 is provided with an air flow passage 203 that communicates with a pump, a cuff belt, and the like. ) 204 is opened.

  Inside the main body housing 201, an armature 220 as a movable element is disposed at the center, and a permanent magnet 210 and yokes 211 and 212 are disposed on the outer periphery thereof. A drive coil 225 mounted on the armature 220 is inserted into the gap between the yokes 211 and 212, and the coil 225 is disposed so as to cross the magnetic field between the yokes 211 and 212.

  The head of the armature 220 is opposed to the center of the front housing 202, and a rubber valve (orifice packing) 230 for opening and closing the air outlet 204 is provided at the head of the armature 220 so as to face the air outlet 204. Is provided. The armature 220 is supported on the main body housing 201 by two leaf springs 241 and 242 at both ends in the displacement direction. The leaf springs 241 and 242 cause the valve to open, that is, the rubber valve 230 is air-flowed. It is biased in a direction away from the outlet 204.

  When blood pressure is measured using this electric exhaust valve, first, a current crossing the magnetic field between the yokes 211 and 212 is caused to flow through the coil 225 by energizing the drive coil 225. Then, a driving force is generated in the coil 225, the armature 220 moves against the urging force of the leaf springs 241 and 242, and the rubber valve 230 closes the air circulation port 204. In this state, air is supplied into the cuff belt by a pressurizing pump to pressurize the cuff belt.

  Next, the process proceeds to the cuff zone decompression process. At this time, the driving force acting on the drive coil 225 is weakened by gradually decreasing the current supplied to the drive coil 225. Then, the armature 220 moves toward the initial position by the urging force of the leaf springs 241 and 242, the rubber valve 230 moves away from the air circulation port 204, and the valve gradually opens. The air is exhausted to the outside little by little. The blood pressure is measured in the process of depressurization in the cuff zone by this minute amount of exhaust.

Japanese Patent No. 3029073

  By the way, the conventional electric exhaust valve is a system in which an armature equipped with a coil is moved by using the magnetic force of a permanent magnet to open and close the valve. It was easy to become heavy. Moreover, in order to obtain the driving force necessary to fully close so as not to leak air at the upper limit pressure (usually about 280 mmHg to 300 mmHg), the weight of the coil tends to increase, and the movable part tends to become heavier.

  Further, in order to increase the accuracy of exhaust, it is necessary to move the movable part, which tends to be heavy, smoothly and accurately in a state of being biased by a spring.

  Therefore, there is a problem that it is difficult to form a compact structure, and a precise assembling work is required, resulting in an increase in production cost.

  In addition, when the movable part becomes heavy, for example, when applied to a wrist sphygmomanometer, the exhaust characteristics may change due to the difference in posture during blood pressure measurement, and as a result, the measurement accuracy may be adversely affected. It was.

  In addition, the conventional movable coil type electric exhaust valve that extracts power by passing the current flowing through the coil across the magnetic field generated by the permanent magnet adjusts the valve opening by generating a force proportional to the current flowing through the coil. At first glance, it seems that pressure reduction control in proportion to the current is possible. However, in actuality, for example, an uneven surface of a rubber valve provided for exhausting at a slow speed (an uneven surface may be provided on the pressure contact surface of the rubber valve). When pressing, there is a valve characteristic that it can be pressed with a weak force at the beginning of pressing, but after that it must be pressed with a strong force as the amount of restriction is increased, and as a result, it is proportional to the current supplied to the coil. However, there is a problem that it is difficult to perform the control and the troublesome control must be performed.

  In consideration of the above circumstances, the present invention is an electric exhaust valve that has a simple and compact structure, can be easily assembled, can reduce production costs, and can exhibit stable characteristics regardless of a difference in posture. And it aims at providing a blood pressure meter provided with it.

  The electric exhaust valve of the invention of claim 1 is a magnetic member having an exhaust outlet opened on an end surface, an exciting coil that magnetizes the magnetic member by energization, and the magnetic member is magnetized. A movable piece that is magnetically attracted from an initial position toward an end surface of the magnetic member having an opening at the outlet, an urging means that urges the movable piece to an initial position, and the movable piece. A valve body that adjusts the opening degree of the outlet according to a suction position when the magnetic member is magnetically attracted toward the end surface of the magnetic member against the biasing force of the biasing means. And

  According to a second aspect of the present invention, there is provided a rod-shaped stationary core having an exhaust outlet opened at one end face in the longitudinal direction and an outer peripheral portion of the stationary core, and the stationary core is magnetized in the longitudinal direction by energization. An exciting coil, a movable iron piece that is magnetically attracted from an initial position toward an end surface of the fixed core that is open at the outlet when the fixed iron core is magnetized, and holding the movable iron piece while biasing the movable iron piece to the initial position And the opening of the outlet according to the suction position when the movable iron piece is magnetically attracted toward the end face of the fixed core against the urging force of the leaf spring. And a valve body for adjusting the pressure.

  According to a third aspect of the present invention, in the second aspect, a communication hole extending in the longitudinal direction of the fixed iron core is formed inside the rod-shaped fixed iron core, and one end of the communication hole is used as the outflow port in the longitudinal direction of the fixed iron core. The other end of the communication hole is opened as an inflow port on the other end surface in the longitudinal direction of the fixed iron core.

  According to a fourth aspect of the present invention, in the third aspect, the fixed iron core and the exciting coil are accommodated in a bottomed cylindrical housing, and the other end portion of the fixed iron core having the inflow port on an end surface thereof The fixed end of the leaf spring is supported by a bobbin around which the housing or the exciting coil is wound, and the open end of the housing is closed with a lid so as to protrude from the bottom wall of the housing. The movable iron piece and the leaf spring together with the iron core and the exciting coil are housed in a space sealed with a housing and a lid.

  According to a fifth aspect of the present invention, in the fourth aspect, the leaf spring is supported at both ends, the valve element is disposed at an intermediate point of the leaf spring supported at both ends, and a magnetic attraction point between the movable iron piece and the fixed iron core. Is set around the place where the valve element is disposed.

  According to a sixth aspect of the present invention, in the fourth aspect, the leaf spring is cantilever-supported, the valve element is disposed at a free end of the cantilever-supported leaf spring, and the magnetism between the movable iron piece and the fixed iron core is provided. The suction point is set around the place where the valve body is arranged, or outside the place where the valve body is arranged when viewed from the cantilever support point of the leaf spring.

  According to a seventh aspect of the present invention, in the sixth aspect, a yoke is attached to one end face of the fixed iron core, and the movable iron piece is formed in a size corresponding to the yoke.

  According to an eighth aspect of the present invention, in any one of the second to seventh aspects, a rubber valve that press-contacts around the outflow port is provided as the valve body.

  A ninth aspect of the invention is characterized in that, in any one of the second to eighth aspects, the outlet is formed in a resin or rubber nozzle attached to an end of the communication hole of the fixed core. And

  According to a tenth aspect of the present invention, in any one of the second to ninth aspects, the outlet is formed in a conical concave shape, and the valve body is formed in a conical convex shape that fits into the conical concave outlet. It is characterized by being.

  An eleventh aspect of the present invention is the method according to any one of the second to tenth aspects, wherein at least one of the pressure contact surface on the fixed iron core side and the pressure contact surface on the valve body side that are in pressure contact with each other in order to reduce the opening degree of the outflow port, The present invention is characterized in that an unevenness for forming a path is provided.

  The sphygmomanometer according to claim 12 is an electric exhaust valve according to any one of claims 1 to 11 as an exhaust valve for discharging air supplied into a cuff belt wound around a part of a human body such as an arm or a wrist. It is characterized by using.

  According to the first and second aspects of the present invention, the magnetic member (fixed iron core) is magnetized by energizing the exciting coil, and the movable piece (movable iron piece) is attracted by the magnetic attraction force. Because the opening of the outlet opening on the end face of the magnetic member (fixed iron core) is adjusted by the valve provided on the (movable iron piece), it is easy to use with a small number of parts without using a high-cost permanent magnet. The structure is compact and can be manufactured at low cost. In addition, since the movable piece (movable iron piece) with a valve body is attracted by magnetic attraction force, the movable part can be reduced in weight, thereby assembling work including attachment of biasing means (leaf spring) Can be facilitated.

  In addition, since the movable part that plays an important role in adjusting the throttle opening can be reduced in weight, changes in the valve characteristics due to posture differences can be minimized, for example, as with a wrist sphygmomanometer. Even when applied to applications that are highly likely to be used in a posture, stable characteristics can be exhibited, and high-precision measurement is possible.

  When the current flowing through the coil is increased, the movable piece (movable iron piece) is attracted to the magnetic member (fixed iron core) according to the generated electromagnetic force, but the attractive force at that time is inversely proportional to the square of the distance. Therefore, for example, when a fine path for throttling is secured while the rubber valve is crushed by the suction force, the linearity of the leakage amount (exhaust amount) with respect to the supply current can be improved. That is, the relationship between the force required to crush the rubber valve and the attractive force actually generated between the magnetic member (fixed iron core) and the movable piece (movable iron piece) can be brought closer to a linear relationship. . Therefore, the control characteristic of the slow depressurization speed can be improved, and the blood pressure can be measured with high accuracy with the stable depressurization characteristic.

  In particular, in the invention of claim 2, since the leaf spring is used as the biasing means, the movable piece (movable iron piece) can be easily supported while applying the biasing force, and the structure is made compact. Can do.

  According to the invention of claim 3, a communication hole extending in the longitudinal direction of the fixed iron core is formed inside the rod-shaped fixed iron core of the invention of claim 2, and one end of the communication hole is used as an outlet and the length of the fixed iron core. The other end of the communication hole is used as an inflow opening at the other end surface in the longitudinal direction of the fixed core, that is, the air passage required for the fixed core itself, not the housing Therefore, the structure can be simplified, the assembly can be facilitated, and the productivity can be improved.

  According to the invention of claim 4, the fixed iron core and the exciting coil in the invention of claim 3 are accommodated inside the bottomed cylindrical housing, and the other end portion of the fixed iron core having an inflow port on the end surface is provided. , Projecting outward from the bottom wall of the housing, while supporting the fixed end of the leaf spring with a bobbin around which the housing or excitation coil is wound, and closing the open end of the housing with a lid, thereby fixing the fixed core and the excitation coil In addition, since the movable piece and the leaf spring are accommodated in the space sealed by the housing and the lid, a compact and easily assembled structure can be realized.

  According to the invention of claim 5, since the leaf spring in the invention of claim 4 is supported at both ends and the movable iron piece provided with the valve body is arranged at the intermediate point of the leaf spring supported at both ends, the movable iron piece is supported in a balanced manner. Can do. In addition, since the magnetic attraction point between the movable iron piece and the fixed iron core is set around the location where the valve element is placed, a large force is applied to the flow restrictor by the valve element and the outlet, which is the action point, with a small drive power. Can be added.

  According to the invention of claim 6, the leaf spring in the invention of claim 4 is cantilever-supported, and the movable iron piece provided with the valve element is arranged at the free end of the cantilever-supported leaf spring. In addition to being easy, the movable iron piece at the free end can be attracted toward the fixed iron core with a weak magnetic attraction. In addition, since the magnetic attraction point between the movable iron piece and the fixed iron core is set around the place where the valve element is arranged, or outside the place where the valve element is arranged when viewed from the cantilever support point of the leaf spring, With a small driving power, a large force can be applied to the flow restrictor by the valve body and the outlet that are the operating points.

  According to the invention of claim 7, since the yoke is attached to one end surface of the fixed iron core in the invention of claim 6 and the movable iron piece is formed in a size corresponding to the yoke, it is limited to the size of the end surface of the fixed iron core. In addition, the magnetic suction surface having an effective size can be made to face the movable iron piece, the suction performance can be improved, and the valve performance can be stabilized.

  According to the eighth aspect of the present invention, since the rubber valve that press-contacts around the outlet is provided as the valve body, it is possible to ensure the prevention of air leakage when fully closed. Also, the suction posture difference of the movable iron piece can be absorbed by the elasticity of the rubber.

  According to invention of Claim 9, since the said outflow port was formed in the resin-made or rubber-made nozzle attached to the edge part of the communicating hole of a stationary iron core, the outflow port which requires a fine process is formed by resin molding. Easy to make. In addition, if multiple types of nozzles with different diameters of the outlet and the degree of unevenness (roughness) of the pressure contact surface with the valve body around the outlet are prepared, an appropriate one of them is selected. By simply mounting, it is possible to create an electric exhaust valve of a type with easily different characteristics while keeping the other components identical.

  According to the invention of claim 10, since the outlet is formed in a conical concave shape, and the valve body is formed in a conical convex shape that fits into the conical concave outlet, a conical shape is formed between the valve body and the outlet. The pressure contact surface (valve seat) can be made, making it easier to adjust the throttle.

  According to the eleventh aspect of the present invention, since the concave and convex portions for forming the micro flow path are provided on at least one of the press contact surface on the fixed iron core side and the press contact surface on the valve body side that are in pressure contact with each other in order to reduce the opening degree of the outlet, Flow rate adjustment (micro decompression) is possible.

  According to the invention of claim 12, since the electric exhaust valve according to any one of claims 1 to 11 is used, a sphygmomanometer that is compact, inexpensive, and stable in performance can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a side sectional view (a) of the electric exhaust valve 10 of the first embodiment and a front view (b) viewed from the terminal side.

  In the figure, reference numeral 11 denotes a bottomed cylindrical housing (made of resin) having an open end, and a small-diameter through hole 11a is formed at the center of the bottom wall of the housing 11. Inside the housing 11, a fixed iron core (magnetic member) 12 is disposed at the center, and an excitation coil 13 wound around a bobbin 14 is disposed on the outer periphery thereof. The exciting coil 13 is for magnetizing the rod-shaped fixed iron core 12 in the longitudinal direction by energization.

  A communication hole 16 extending in the longitudinal direction of the fixed iron core 12 is formed inside the fixed iron core 12, and one end of the communication hole 16 is an end surface of a convex portion 12 c formed at one end in the longitudinal direction of the fixed iron core 12. In addition, an exhaust outlet (exhaust port) 17 is opened. Further, the other end of the communication hole 16 is opened at the end face of the other end portion 12a of the fixed iron core 12 as an inflow port 18 communicating with the pump and the cuff belt.

  One end 12a of the fixed iron core 12 having the inlet 18 on the end surface is formed with a small diameter through the step, and the small diameter portion is in a state where the step is abutted against the bottom wall of the housing 11. By being inserted into the through hole 11 a in the bottom wall, one end 12 a of the fixed iron core 12 protrudes from the bottom wall of the housing 11 to the outside.

  The fixed iron core 12 passes through the center hole of the bobbin 14 in the housing 11, and the circular end surface 12b on the side having the outflow port 17 is formed flat as a magnetic attraction surface. And the convex part 12c which has the outflow port 17 in the end surface in the form protruded slightly in the center is formed. The bobbin 14 is fitted to the inner periphery of the housing 11 and has a bracket 19 for attaching a leaf spring 20 described later integrally with the end.

  Further, on the open end side in the housing 11, it is opposed to the end surface 12 b of the fixed core 12 having the outlet 17, and when the fixed core 12 is magnetized, it is magnetic from the initial position toward the end surface 12 b of the fixed core 12. A movable iron piece 21 to be sucked is disposed, and a leaf spring (biasing means) 20 is disposed to bias and hold the movable iron piece 21 at an initial position away from the outlet 17.

  Moreover, the recessed part 21a in which the convex part 12c can enter is formed in the part facing the convex part 12c by the side of the fixed core 12 among the opposing surfaces with the end surface 12b of the fixed iron core 12 of the movable iron piece 21, A disk-shaped rubber valve (valve element) 22 is disposed on the bottom surface of the recess 21a and is fixed by, for example, bonding. When the movable iron piece 21 is magnetically attracted toward the end surface 12b of the fixed core 12 against the urging force of the leaf spring 20, the rubber valve 22 adjusts the opening degree of the outlet 17 according to the suction position. Is. Here, the portions that attract strongly when the fixed iron core 12 is magnetized (magnetic attraction point = power point) are the annular portions around the recess 21a and around the convex portion 12c.

  The leaf spring 20 that holds the movable iron piece 21 is a material having an appropriate elasticity and strength, for example, a flat plate made of phosphor bronze, brass, nonmagnetic stainless steel, etc., having a special shape press-cut. It has a portion 20a, a hairpin portion 20b formed in a point-symmetric hairpin shape on both sides thereof, and a rectangular fixing portion 20c to which each end of the hairpin portion 20b is connected. Then, both ends are supported by fixing the fixing portions 20c at both ends to the bracket 19 of the bobbin 14 with, for example, screws 24 or the like. Accordingly, the rubber valve 22 disposed on the movable iron piece 21 is held at the middle point of the leaf spring 20 supported at both ends, and the rubber valve 22 is disposed at the magnetic attraction point (power point) between the movable iron piece 21 and the fixed iron core 12. It is set around the marked part.

  In the assembled state, the open end of the housing 11 is closed by the lid body 26, so that the movable iron piece 21 having the rubber valve 22 and the leaf spring together with the bobbin 14 around which the fixed iron core 12 and the exciting coil 13 are wound. 20 is accommodated in a space sealed by the housing 11 and the lid body 26. Therefore, the leaf spring 20 and the like can be protected from dust and external vibration.

  Note that both ends of the conducting wire of the exciting coil 13 are connected to a terminal 27 protruding from the lid body 26. The housing 11 and / or the lid 26 are formed with an opening and a gap (not shown) for releasing the exhausted air.

  The electric exhaust valve 10 having the above configuration can be applied as an exhaust valve of a sphygmomanometer. FIG. 11 is a system diagram showing a configuration of a sphygmomanometer to which the electric exhaust valve 10 is applied.

  The sphygmomanometer 110 includes a cuff band 111 wound around a part of a human body such as an arm, wrist, or finger, a pressure pump 112 that supplies compressed air to the cuff band 111, and a pressure that detects air pressure in the cuff band 111. Based on the detection signal from the pressure gauge 113, the electric exhaust valve 120 (corresponding to the electric exhaust valve 10) that discharges the air in the cuff zone 111 to the atmosphere at a constant speed through the outlet pipe 114. And a microcomputer 115 for supplying air at a constant pressure to the cuff belt 111 and controlling the operation of the electric exhaust valve 120 to discharge air from the cuff belt 111 at a constant speed. It is configured.

  Next, the operation of the electric exhaust valve 10 (120) applied to the sphygmomanometer 110 as described above will be described with reference to FIG.

  Before the exciting coil 13 is energized, the movable iron piece 21 is urged away from the circulation port 17 by the urging force of the leaf spring 20, so that the circulation port 17 is completely opened.

  When the exciting coil 13 is energized from this state, the fixed iron core 12 is magnetized in the longitudinal direction. Then, when a magnetic attractive force is generated on the end surface 12 b of the fixed iron core 12, the movable iron piece 21 is attracted to the end surface 12 b side of the fixed iron core 12. By being sucked to the maximum, the rubber valve 22 provided on the movable iron piece 21 comes into pressure contact with the end surface of the convex portion 12c of the fixed core 12 without a gap, and the outflow port 17 opened on the end surface 12c is fully closed. In this state, the pressurizing pump 112 is operated to supply air into the cuff band 111 to pressurize the cuff band 11.

  Next, the process proceeds to the pressure reducing process of the cuff band 111. At this time, the magnetic force generated in the fixed iron core 12 is weakened by gradually decreasing the current supplied to the exciting coil 13. Then, the movable iron piece 21 moves toward the initial position by the urging force of the leaf spring 20, the rubber valve 22 moves away from the outlet 17, and the valve gradually opens, and the air in the cuff belt 111 passes through the outlet 17. Exhaust by a small amount. The blood pressure is measured in the process of depressurization in the cuff belt 111 by this minute amount of exhaust.

  The electric exhaust valve 10 of this embodiment is compactly configured with a small number of parts without using a permanent magnet having a high unit price, and can be manufactured at low cost. In addition, it is not a moving coil system, but a system that adjusts the valve opening by attracting the movable iron piece 21 with the rubber valve 22 by the magnetic attraction force generated in the fixed iron core 12, so that it differs from the conventional example of the moving coil system. Thus, the movable part can be reduced in weight, and the assembly work including the attachment of the leaf spring 20 can be facilitated.

  In addition, since the movable part that plays an important role in adjusting the throttle opening can be reduced in weight, changes in valve characteristics due to posture differences can be minimized, for example, as with a wrist sphygmomanometer. Even when applied to applications that are highly likely to be used in a posture, stable characteristics can be exhibited, and high-precision measurement is possible.

  Further, when the current flowing through the exciting coil 13 is increased, the movable iron piece 21 is attracted to the end surface 12b of the fixed core 12 according to the generated electromagnetic force, but the attractive force at that time is inversely proportional to the square of the distance. Therefore, the linearity of the leakage amount (exhaust amount) with respect to the supply current can be improved when the throttle path is secured while the rubber valve 22 is crushed by the suction force. That is, the relationship between the force necessary for crushing the rubber valve 22 and the suction force actually generated between the fixed iron core 12 and the movable iron piece 21 can be brought close to a linear relationship. Therefore, the control characteristic of the slow depressurization speed can be improved, and the blood pressure can be measured with high accuracy with stable depressurization characteristics.

  Moreover, in the electric exhaust valve 10 of this embodiment, since the leaf | plate spring 20 is used as an urging means, while supporting the movable iron piece 21 while providing urging | biasing force, it can take a compact structure. can do.

  Further, a communication hole 16 is formed inside the rod-shaped fixed iron core 12, and one end of the communication hole 16 is opened as an outlet 17 on one end surface 12 b in the longitudinal direction of the fixed iron core 12, and the other end of the communication hole 16. Is opened at the other end surface in the longitudinal direction of the fixed iron core 12 as the inlet 18, that is, all the necessary air passages are formed not in the housing 11 but in the fixed iron core 12 itself. Can be simplified, and assembly can be facilitated and productivity can be improved.

  Further, the fixed core 12 and the exciting coil 13 are accommodated in the bottomed cylindrical housing 11, and the other end 12 a of the fixed core 12 having the inlet 18 on the end surface is passed through the bottom wall of the housing 11. On the other hand, the fixed end of the leaf spring 20 is supported by a bobbin 14 around which an exciting coil 13 is wound, and the open end of the housing 11 is closed by a lid body 26, whereby the fixed core 12 and Since the movable iron piece 21 and the leaf spring 20 are housed in the space sealed by the housing 11 and the lid body 26 together with the exciting coil 13, a compact and easily assembled structure can be realized.

  The bracket 19 that supports the leaf spring 20 can be provided not on the bobbin 14 but on the housing 11 or the lid 26 (in this case, it can be regarded as a part of the housing).

  Further, the electric exhaust valve 10 of this embodiment supports the leaf spring 20 at both ends, and the movable iron piece 21 with the rubber valve 22 is disposed at the middle point of the leaf spring 20 supported at both ends. The attached movable iron piece 21 can be supported. Further, since the magnetic attraction point (power point) between the movable iron piece 21 and the fixed iron core 12 is set so as to surround the portion where the rubber valve 22 is disposed, the rubber valve which is the working point with a small driving power. A large force can be applied to the flow restrictor by the outlet 22 and the outlet 17.

  Moreover, since the rubber valve 22 which press-contacts around the outflow port 17 is provided as a valve body, it can be ensured that air leakage is prevented when the valve is fully closed. Further, the suction posture difference of the movable iron piece 21 can be absorbed by the elasticity of the rubber.

FIG. 2 is a side sectional view (a) of the electric exhaust valve 10B of the second embodiment and a front view (b) viewed from the terminal side.
In the electric exhaust valve 10B, the leaf spring 20B is formed in a simple rectangular shape, and the leaf spring 20B is cantilevered by being fixed to the bracket 19 with, for example, a screw 24 or the like with one end portion as a fixed end. The movable iron piece 21 is attached to the free end of the plate spring 20B that is cantilevered, and the rubber valve 22 is attached to the recess 21a of the movable iron piece 21. Other configurations are the same as those of the first embodiment. In this case, the magnetic attraction point (power point) between the movable iron piece 21 and the fixed iron core 12 is set around the place where the rubber valve 22 is disposed.

  Thus, when the leaf spring 20B is cantilevered and the movable iron piece 21 with the rubber valve 22 is disposed at the free end of the cantilevered leaf spring 20B, the leaf spring 20B can be easily attached and the movable iron piece 21 can be attracted toward the fixed iron core 12 with a weaker magnetic attraction than in the case of supporting both ends.

  Further, since the magnetic attraction point between the movable iron piece 21 and the fixed iron core 12 is set around the place where the rubber valve 22 is disposed, the flow rate by the rubber valve 22 and the outlet 17 which are the action points can be obtained with a small driving power. A large force can be applied to the throttle portion.

FIG. 3 is an enlarged view of a main part of the electric exhaust valve of the third embodiment.
In this electric exhaust valve, the shape of the movable iron piece 32 attached to the free end of the cantilever-supported plate spring 20B is set to a curved plate shape different from that of the second embodiment. That is, a stepped portion 12e is provided on the end surface of the fixed iron core 12, and a yoke 30 extending long in the direction of extension of the free end of the leaf spring 20B is fitted therein, and the movable iron piece has a size corresponding to the yoke 30. 32 is formed. Then, a bent piece 32 a that is close to the magnetic attraction surface 30 a of the yoke 30 is provided on the extended portion of the movable iron piece 32 that extends in the free end extension direction of the leaf spring 20 </ b> B.

  In this case, the distance between the opposed surfaces of the bent piece 32a and the yoke 30 is set larger than the distance between the opposed surfaces of the rubber valve 22 and the convex portion 12c of the fixed iron core 12, and the rubber valve is surely secured at the maximum magnetic attraction. The outlet 17 can be closed by 22. Further, the magnetic attraction point (force point) between the movable iron piece 32 and the fixed iron core 12 is set outside the portion (action point) where the rubber valve 22 is disposed as seen from the cantilever support point of the leaf spring 20B. .

  Thus, when the yoke 30 is provided at the end of the fixed iron core 12, the suction surface of an effective size can be opposed to the movable iron piece 32 without being limited to the size of the end surface of the fixed iron core 12, The suction performance can be improved and the valve performance can be stabilized. In addition, since the magnetic attraction point (power point) between the movable iron piece 32 and the fixed iron core 12 is set outside the place where the rubber valve 22 is disposed, it can flow with the rubber valve 22 that is the working point with a small driving power. A large force can be applied to the flow restrictor by the outlet 17.

FIG. 4 is an enlarged view of a main part of the electric exhaust valve of the fourth embodiment.
In this electric exhaust valve, the outlet 17 is formed in a resin (or rubber) nozzle 37 attached to the end of the communication hole 16 of the fixed iron core 12. That is, the troublesome outlet 17 is formed in the resin nozzle 37 at the molding stage, and this nozzle 37 is press-fitted or bonded to the fitting portion 12 f formed at the end of the communication hole 16 of the fixed core 12. It is fixed by.

  Thus, by forming the outlet 17 in the resin nozzle 37, the outlet 17 that requires fine processing can be easily made by resin molding, and productivity is improved. In addition, if a plurality of types of nozzles 37 having different diameters (roughness) of the pressure contact surface with the valve body around the outlet are prepared, an appropriate one of them is selected. By simply mounting, it is possible to easily create an electric exhaust valve of a type with different characteristics while keeping the other components exactly the same.

  In the configuration of each of the embodiments described above, in order to reduce the opening degree of the outflow port 17, at least one of the pressure contact surface on the fixed iron core 12 side and the pressure contact surface on the rubber valve 22 side that are in pressure contact with each other May be provided. When the nozzle 37 is made of rubber, the valve element side may be formed of a hard material.

  In the example of FIG. 5, many minute convex portions 41 are regularly or irregularly scattered on the end surface of the convex portion 12 c of the fixed iron core 12. Further, in the example of FIG. 6, a large number of grooves (small concave portions) 42 are formed radially on the end face of the convex portion 12 c of the fixed iron core 12.

  In this way, by forming minute irregularities on the wall surface around the outlet port 17, minute flow rate adjustment (minute decompression) becomes possible. When the resin or rubber nozzle 37 is attached to the end of the fixed iron core 12 as shown in FIG. 4, the minute irregularities on the fixed iron core 12 side as shown in FIG. Can be formed.

7 and 8 show an example in which minute irregularities are provided on the rubber valve side facing the end face of the fixed core 12.
In the rubber valve 22B of FIG. 7, a large number of minute conical (conical or pyramidal) protrusions 43 are regularly arranged on the pressure contact surface on the fixed iron core 12 side. Further, in the rubber valve 22C of FIG. 8, a large number of minute chevron ridges 44 are provided in parallel on the pressure contact surface on the fixed iron core 12 side. When the protrusions 43 and the protrusions 44 (minute protrusions) are formed on the pressure contact surfaces of the rubber valves 22B and 22C in this way, the protrusions 43 and the protrusions 44 are crushed by being pressed against the protrusions 12c on the fixed core 12 side. A minute gap is formed, and air leaks therefrom, and a minute flow rate can be controlled.

FIG. 9 is an enlarged cross-sectional view of a main part of the electric exhaust valve of the fifth embodiment.
In this electric exhaust valve, the outlet 57 on the fixed iron core 12 side is formed in a conical concave shape, and the rubber valve 50 is formed in a conical convex shape that fits in the conical concave outlet 57. In this example, the conical outer surface 50a of the rubber valve 50 is in pressure contact with the conical inner surface 57a on the outlet 57 side when the valve is closed. Further, the rubber valve 50 is attached to the leaf spring 20 </ b> B together with the movable iron piece 21 by a locking portion 50 e protruding from the upper end.

  Thus, when the outlet 57 is formed in a conical concave shape and the rubber valve 50 is formed in a conical convex shape, the opposing surface of the rubber valve 50 and the outlet 57 can be a conical surface. It becomes easy to do.

  As shown in FIG. 10, by forming the minute irregularities 52 radially on the conical outer surface 50a of the rubber valve 50, it is possible to secure a minute throttle channel that is crushed and deformed by pressure contact.

  Moreover, in the said embodiment, the case where the movable iron piece 21 was urged | biased to the initial position by the leaf | plate springs 20 and 20B was shown, However, the movable iron piece 21 is urged | biased to an initial position using urging means other than a leaf | plate spring. Also good.

  Moreover, in the said embodiment, although the outflow port 17 of the end surface of the fixed iron core 12 is connected to the communicating hole 16 penetrated in the longitudinal direction of the fixed iron core 12, an air passage is formed in the other path, and the outflow port is formed. 17 may be communicated.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of 1st Embodiment of this invention, (a) is sectional side view, (b) is the front view seen from the terminal side. It is a block diagram of 2nd Embodiment of this invention, (a) is sectional side view, (b) is the front view seen from the terminal side. It is a principal part expanded sectional view of 3rd Embodiment of this invention. It is a principal part expanded sectional view of 4th Embodiment of this invention. It is a principal part enlarged view which shows the modification of the outflow outlet periphery of the fixed iron core edge part in each said embodiment, (a) is a front view, (b) is a side view. It is a principal part enlarged view which shows the other modification of the outflow port periphery of the fixed iron core edge part in each said embodiment, (a) is a front view, (b) is a side view. It is a principal part enlarged view perspective view which shows the modification of the rubber valve in each said embodiment. It is a principal part enlarged view perspective view which shows the other modification of the rubber valve in each said embodiment. It is a principal part expanded sectional view of 5th Embodiment of this invention. The modification of the rubber valve in the said 5th Embodiment is shown, (a) is a side view, (b) is a front view. It is a systematic diagram showing an example of a sphygmomanometer equipped with the electric exhaust valve of the present invention. It is a sectional side view of the conventional electric exhaust valve.

Explanation of symbols

10, 10B Electric exhaust valve 11 Housing 12 Fixed iron core (magnetic member)
12a End 12b End 12c Protrusion 13 Excitation coil 14 Bobbin 16 Communication hole 17 Outlet 18 Inlet 19 Bracket 20, 20B Leaf spring (biasing means)
21 Movable iron piece (movable piece)
22, 22B, 22C Rubber valve (valve)
26 Lid 30 Yoke 32 Movable iron piece 37 Nozzle 41 Micro convex part 42 Groove (micro concave part)
43 Protrusions (micro-projections)
44 ridges (micro-projections)
50 Conical convex rubber valve 57 Conical concave outlet 111 Cuff belt 112 Pressure pump 120 Electric exhaust valve

Claims (12)

A magnetic member having an exhaust outlet on the end face; and
An exciting coil for magnetizing the magnetic member by energization;
When the magnetic member is magnetized, a movable piece that is magnetically attracted from an initial position toward an end surface of the magnetic member having an opening at the outlet,
Biasing means for biasing the movable piece to an initial position;
Provided on the movable piece, the opening of the outlet is adjusted according to the suction position when the movable piece is magnetically attracted toward the end surface of the magnetic member against the biasing force of the biasing means. The disc,
An electrically driven exhaust valve comprising: A rod-shaped fixed iron core having an outlet for exhaust at one end face in the longitudinal direction; and
An excitation coil that is disposed on the outer periphery of the fixed core and magnetizes the fixed core in the longitudinal direction by energization;
When the fixed iron core is magnetized, a movable iron piece that is magnetically attracted from an initial position toward an end surface of the fixed iron core that is opened at the outlet.
A leaf spring for holding the movable iron piece while biasing it to an initial position;
A valve body that is provided on the movable iron piece and adjusts the opening degree of the outlet according to the suction position when the movable iron piece is magnetically attracted toward the end face of the fixed iron core against the biasing force of the leaf spring. When,
An electrically driven exhaust valve comprising:   A communication hole extending in the longitudinal direction of the fixed iron core is formed inside the rod-shaped fixed iron core, and one end of the communication hole is opened as one outlet surface of the fixed iron core in the longitudinal direction. 3. The motor-driven exhaust valve according to claim 2, wherein the other end of the motor is opened as an inflow port on the other end surface in the longitudinal direction of the fixed iron core.   The fixed iron core and the exciting coil are housed inside a bottomed cylindrical housing, and the other end of the fixed iron core having the inlet is provided on the end surface thereof to protrude outside from the bottom wall of the housing, The fixed end of the leaf spring is supported by a bobbin around which the housing or the exciting coil is wound, and the opening end of the housing is closed with a lid, so that the movable iron piece and the leaf spring are brought together with the stationary iron core and the exciting coil. The electric exhaust valve according to claim 3, wherein the electric exhaust valve is accommodated in a space sealed with a housing and a lid.   The leaf spring is supported at both ends, the valve body is disposed at an intermediate point of the leaf spring supported at both ends, and the magnetic attraction point between the movable iron piece and the fixed iron core is around the location where the valve body is disposed. The electric exhaust valve according to claim 4, wherein the electric exhaust valve is set as follows.   The leaf spring is cantilever-supported, the valve body is disposed at the free end of the cantilever-supported leaf spring, and the magnetic attraction point between the movable iron piece and the fixed iron core is the place where the valve body is disposed. 5. The electric exhaust valve according to claim 4, wherein the electric exhaust valve is set to a periphery of the valve body or outside a portion where the valve body is disposed when viewed from a cantilever support point of the leaf spring.   The electric exhaust valve according to claim 6, wherein a yoke is attached to one end face of the fixed iron core, and the movable iron piece is formed in a size corresponding to the yoke.   The electric exhaust valve according to any one of claims 2 to 7, wherein a rubber valve that press-contacts around the outflow port is provided as the valve body.   The electric exhaust valve according to any one of claims 2 to 8, wherein the outlet is formed in a resin or rubber nozzle attached to an end of the communication hole of the fixed iron core.   The said outflow port is formed in conical concave shape, and the said valve body is formed in the conical convex shape fitted in the said conical concave outflow port, The any one of Claims 2-9 characterized by the above-mentioned. Electric exhaust valve.   3. An unevenness for forming a micro flow path is provided on at least one of the pressure contact surface on the fixed iron core side and the pressure contact surface on the valve body side that are in pressure contact with each other in order to reduce the opening of the outlet. The electric exhaust valve according to any one of 10.   The electric exhaust valve according to any one of claims 1 to 11 is used as an exhaust valve for discharging air supplied in a cuff belt wound around a part such as an arm or wrist of a human body. Sphygmomanometer.

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