JP6027517B2 - Solenoid valve, diaphragm assembly and drive shaft connection structure - Google Patents

Description

  The present invention holds the outer edge of the diaphragm between the valve body provided with the valve seat, the diaphragm assembly in which the shaft member is fixed to the diaphragm that contacts or separates from the valve seat, and the valve body. A diaphragm holding member through which the shaft member is inserted, and a solenoid that abuts the diaphragm holding member and the movable iron core is biased in the valve seat direction by the first biasing member, and moves the shaft member together with the movable iron core. The present invention relates to an electromagnetic valve for bringing a diaphragm into contact with or separating from a valve seat, and a structure for connecting a diaphragm assembly and a drive shaft.

  For example, in a medical device, a chemical solution such as hypochlorous acid or acetic acid whose flow rate is controlled by a solenoid valve is flowed for sterilization or cleaning. A diaphragm is used for the solenoid valve in order to make the wetted part metal-free. Medical devices are becoming more compact and the installation space for solenoid valves is becoming narrower. Therefore, the solenoid valve is required to be downsized.

  For example, in the electromagnetic valve 101 shown in FIG. 4, a diaphragm 104 that contacts or separates from the valve seat 111 is sandwiched between the valve body 102 and the diaphragm holding member 103. In the solenoid 107, the movable iron core 108 projects into the diaphragm holding member 103, and the compression spring 110 constantly urges the movable iron core 108 toward the valve seat 111 side.

  The small solenoid valve 101 has a very small diameter of the diaphragm 104 of about 5 mm. For this reason, the diaphragm 104 cannot be sufficiently secured to be directly connected to the movable iron core 108 to transmit the driving force. Therefore, the diaphragm 104 is configured by fixing a shaft member 105 made of hard resin or metal by insert molding or the like to constitute a diaphragm assembly 106. In the diaphragm assembly 106, a shaft member 105 is connected to a movable iron core 108 of a solenoid 107 via a connecting member 109.

  As shown in FIG. 5, in the connecting member 109, the engagement hole 109a is formed in the horizontal direction in the drawing from the outer peripheral surface, and the engaging projection 108a of the movable core 108 is fitted into the engagement hole 109a. 108. On the other hand, the connecting member 109 is provided with a wedge portion 109c in the middle of the insertion hole 109b formed along the axis from the lower end surface in the drawing so as to protrude toward the center portion. The shaft member 105 is inserted into the insertion hole 109b so as to be press-fitted into the wedge portion 109c, and is connected to the connecting member 109 by being engaged with the wedge portion 109c so as to hook the small diameter portion 105a.

  However, the conventional solenoid valve 101 needs to be provided with a backlash for sliding and engaging the locking projection 108a into the engagement hole 109a. As shown in FIG. A clearance C1 was formed between 108a and the inner wall of the engagement hole 109a. Further, the electromagnetic valve 101 needs to be provided with a backlash for press-fitting the distal end portion of the shaft member 105 into the wedge portion 109c. As shown in FIG. 5, when the valve is closed, the inner wall of the small diameter portion 105a and the wedge portion 109c Clearance C2 was formed between the end faces.

  When the solenoid 107 is energized when the solenoid 107 is closed, the movable iron core 108 is lifted by the clearance C1, and then the locking convex portion 108a is brought into contact with the upper inner wall of the engagement hole 109a. The connection member 109 is lifted up against it. When the connecting member 109 is pulled up by the clearance C2, the wedge portion 109c comes into contact with the side wall of the small diameter portion 105a, the diaphragm assembly 106 is pulled up to the movable iron core 108 via the connecting member 109, and the diaphragm 104 is separated from the valve seat 111. Start letting. That is, since the movable iron core 108 is indirectly connected to the diaphragm assembly 106 via the connecting member 109 in the solenoid valve 101, when the valve is opened from the valve closed state and the set flow rate is controlled, The diaphragm assembly 106 started to be lifted after the clearances C1 and C2 were raised, and the movable iron core 108 had to be moved by a stroke obtained by adding the clearances C1 and C2 to the stroke necessary for controlling the set flow rate.

  Since the sizes of the clearances C1 and C2 are determined by the accumulation of the dimensional tolerances of the movable iron core 108, the connecting member 109, and the shaft member 105, they vary among solids. For this reason, in the solenoid valve 101, the stroke of the movable iron core 108 varies between solids. Since the small solenoid valve 101 has a fine control flow rate, an error of about 10% occurs in the control flow rate even if the stroke variation between solids is small. In order to eliminate this error, in the conventional solenoid valve 101, the clearances C1 and C2 are largely estimated to determine the size of the solenoid 107, and the size of the solenoid 107 cannot be sufficiently reduced.

  Therefore, the inventors of the present application, as shown in FIG. 6, penetrate the shaft member 205 of the diaphragm assembly 206 through the connecting member 209 and replace the male screw portion 205 a of the shaft member 205 with the female screw portion 208 a formed on the movable iron core 208. The electromagnetic valve 201 that directly connects the diaphragm assembly 206 and the movable iron core 208 by screwing has been devised. Such a solenoid valve 201 has no clearance between the connecting member 209 and the shaft member 205, and the movable iron core 208 directly pulls up the diaphragm assembly 206 regardless of the clearance C1 between the movable iron core 208 and the connecting member 209. The size of the solenoid 107 can be selected according to the stroke required for the flow rate, and the electromagnetic valve 201 can be downsized.

  However, when the solenoid valve 201 repeats the valve opening / closing operation, the movable iron core 208 may move up and down and the compression spring 110 may expand and contract, so that a rotational force acts on the movable iron core 208 and the screw loosens to change the stroke. It was. The durability required for the solenoid valve 201 is 5 to 10 million times. However, the solenoid valve 201 has the worst possibility that the valve may not be opened before the durability. The shaft member 205 has a very thin diameter of about 1.8 mm. For this reason, the male screw portion 205a and the female screw portion 208a have to be processed at a very small pitch, which is difficult to screw.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a solenoid valve that can eliminate variation in stroke between solids, and a structure for connecting a diaphragm assembly and a drive shaft. To do.

One embodiment of the present invention has the following configuration.
(1) A valve body provided with a valve seat, a diaphragm assembly in which a shaft member is fixed to a diaphragm that contacts or separates from the valve seat, and an outer edge portion of the diaphragm held between the valve body A diaphragm holding member through which the shaft member is inserted, and a solenoid that is in contact with the diaphragm holding member and whose movable iron core is urged in the valve seat direction by the first urging member, together with the movable iron core In the electromagnetic valve that moves the shaft member to bring the diaphragm into contact with or separates from the valve seat, the biasing force is smaller than that of the first biasing member, and the diaphragm assembly is always biased in the counter valve seat direction. having a biasing member, the second biasing member is a compression spring attached to the outer periphery of the shaft member, the valve seat-side end face of the movable core, the shaft member and the second biasing portion And forming a receiving hole portion for accommodating the.

( 2 ) In the configuration described in ( 1 ), preferably, the shaft member projects from the solenoid side end face of the diaphragm holding member to the solenoid side in a state where the diaphragm is in contact with the valve seat.

( 3 ) A diaphragm assembly in which a shaft member is fixed to a diaphragm that contacts or separates from the valve seat, and a drive shaft that is urged in the valve seat direction by the first urging member and transmits a driving force to the diaphragm assembly. In the connecting structure of the diaphragm assembly to be connected and the drive shaft, the second urging member has a urging force smaller than that of the first urging member and constantly urges the diaphragm assembly in the counter valve seat direction . The urging member is a compression spring attached to the outer periphery of the shaft member, and a housing hole portion for accommodating the shaft member and the second urging member is formed on a valve seat side end surface of the drive shaft. To do.

  In the coupling structure of the solenoid valve and diaphragm assembly and the drive shaft, the second urging member having a smaller urging force than the first urging member urges the shaft member of the diaphragm assembly in the direction opposite to the first urging member and is movable. The diaphragm assembly and the movable iron core are assembled without play so that they always contact the iron core (drive shaft). Also, during the valve opening / closing operation, the shaft member always contacts the movable iron core, and the movable iron core and the diaphragm assembly are integrally displaced. Even if the movable core rotates due to displacement of the movable core or expansion / contraction of the first urging member while repeating the valve opening / closing operation, the diaphragm assembly is kept in contact with the movable core by the urging force of the second urging member. Will not change. Therefore, according to the connecting structure of the solenoid valve and diaphragm assembly and the drive shaft, it is possible to eliminate stroke variation between solids.

  In addition, according to the solenoid valve, the second urging member attached to the outer peripheral surface of the shaft member is housed in the housing hole of the movable iron core, so that the diaphragm assembly and the movable iron core can always be in contact with each other while suppressing the overall height. The device size can be made compact.

  Further, according to the electromagnetic valve, the shaft member projects from the solenoid side end face of the diaphragm holding member to the solenoid side in a state where the diaphragm is in contact with the valve seat, so that the diaphragm assembly, the diaphragm holding member, the second The biasing member and the solenoid can be assembled in this order, and the assemblability is good.

It is sectional drawing of the solenoid valve which concerns on embodiment of this invention. It is sectional drawing which expands and shows the connection structure of the diaphragm assembly of FIG. 1, and a movable iron core, Comprising: A valve closed state is shown. The valve opening state of the expanded sectional view shown in FIG. 2 is shown. It is sectional drawing of the conventional solenoid valve. It is sectional drawing which expands and shows the connection structure of the diaphragm assembly of FIG. 4, and a movable iron core. It is an expanded sectional view of the reference example regarding the connection structure of a diaphragm assembly and a movable iron core.

  DESCRIPTION OF EMBODIMENTS Embodiments of an electromagnetic valve, a diaphragm and a drive shaft connecting structure according to the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a solenoid valve 1 according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing a connection structure between the diaphragm assembly 3 and the movable iron core 14 of FIG. 1 and shows a valve closed state. 3 shows the valve open state of the enlarged cross-sectional view shown in FIG.

  The solenoid valve 1 is used, for example, in a medical device and controls a chemical solution such as hypochlorous acid or acetic acid. In the solenoid valve 1, a solenoid 10 is attached to a valve body 2 via a diaphragm holding member 7. The cover 20 is formed of a nonmagnetic material and is attached so as to cover the solenoid 10 and the diaphragm holding member 7. The electromagnetic valve 1 controls the fluid by applying a driving force of the solenoid 10 to the diaphragm assembly 3 held between the valve body 2 and the diaphragm holding member 7.

  The valve body 2 is formed of a corrosion-resistant material such as a fluororesin, and the first port 2a and the second port 2b communicate with each other via the valve seat 2c. The diaphragm 4 is made of a corrosion-resistant rubber, resin, or the like, and has a valve body portion 4a that contacts or separates from the valve seat 2c, and a thin film portion 4b that extends outward from the outer peripheral surface of the valve body portion 4a. And the outer edge part 4c provided in the outer edge part of the thin film part 4b is provided. Since the diaphragm 4 has a small diameter of about 5 mm and cannot be directly connected to the solenoid 10, the shaft member 5 made of metal or hard resin is fixed to the valve body portion 4 a by insert molding or the like to constitute the diaphragm assembly 3. Yes. The diaphragm holding member 7 is formed of a corrosion-resistant material such as a fluororesin, and the outer edge portion 4 c of the diaphragm 4 is airtightly sandwiched between the valve body 2.

  The solenoid 10 has a coil 11 wound around a coil bobbin 12 having a hollow hole 12a. In the solenoid 10, a fixed iron core 13 is fixed to the upper end opening of the hollow hole 12a, and a movable iron core 14 is slidably loaded from the lower end opening of the hollow hole 12a. The coil 11 is covered with a magnetic cover 15 and a magnetic plate 16 so that a magnetic path for the fixed iron core 13 to attract the movable iron core 14 is easily formed.

  The movable iron core 14 is penetrated by the magnetic plate 16, and the tip portion projects toward the diaphragm holding member 7 side. A magnetic member 17 is disposed between the movable iron core 14 and the magnetic plate 16, and a magnetic path is formed from the magnetic plate 16 to the lower end portion of the movable iron core 14. A flange portion 14 c is provided at the lower end of the movable iron core 14. The first compression spring 18 (an example of a first urging member) is contracted between the flange portion 14c and the magnetic member 17, and constantly urges the movable iron core 14 in the valve seat direction.

  As shown in FIGS. 2 and 3, the lower end portion of the movable iron core 14 and the first compression spring 18 are accommodated in an opening 7 a provided on the solenoid side end surface 7 d of the diaphragm holding member 7 so as to be displaceable. In the diaphragm holding member 7, the shaft member 5 is passed through an insertion hole 7c provided coaxially with the opening 7a. The bottom wall of the opening 7a is provided with a boss 7b at the opening of the insertion hole 7c, and is guided by the boss 7b so that the shaft member 5 can stably reciprocate linearly along the axis.

  As shown in FIG. 2, the shaft member 5 protrudes upward from the solenoid-side end surface 7 d of the diaphragm holding member 7 in a state where the valve body portion 4 a is in contact with the valve seat 2 c. The second compression spring 9 (an example of a second urging member) is inserted into the shaft member 5 so as to abut against a spring receiving stepped portion 7e provided on the end surface of the boss portion 7b, and a retaining ring 8 is inserted into the shaft member 5. By being attached, it is contracted between the retaining ring 8 and the spring receiving stepped portion 7e. Therefore, the shaft member 5 is always urged in the counter valve seat direction by the second compression spring 9. Here, since the shaft member 5 has the retaining ring 8 attached to the outer peripheral surface of the portion protruding from the solenoid-side end surface 7d when the valve is closed, when the valve body 2, the diaphragm assembly 3, and the diaphragm holding member 7 are assembled in this order, 2 It is easy to attach the compression spring 9 to the shaft member 5.

  The movable iron core 14 has an opening 14a on the valve seat side end surface. The distal end portion of the shaft member 5 and the second compression spring 9 are disposed inside the storage hole portion 14a. The spring force of the second compression spring 9 is smaller than the spring force of the first compression spring 18. Therefore, when the coil 11 is not energized, the first compression spring 18 depresses the movable iron core 14 against the second compression spring 9, and pushes the shaft member 5 in the valve seat direction at the bottom surface 14b of the housing hole portion 14a, thereby the diaphragm 4 Is in contact with the valve seat 2c. Since the second compression spring 9 is compressed when the valve is closed in this way, when the coil 11 is energized, the second compression spring 9 expands as the movable iron core 14 rises as shown in FIG. The shaft member 5 is kept pressed against the bottom surface 14b of the storage hole 14a. That is, the solenoid valve 1 is assembled so that the shaft member 5 and the movable iron core 14 are always in contact with no gap.

  The storage hole portion 14a is fitted to the boss portion 7b so that the inner peripheral surface is in sliding contact with the outer peripheral surface of the boss portion 7b. Therefore, the movable iron core 14 is supported by the boss portion 7 b at the lower end where the spring force of the first and second compression springs 18 and 9 acts strongly, and can move stably in the axial direction without contacting the magnetic member 17. .

  In the electromagnetic valve 1, when the coil 11 is energized, the fixed iron core 13 is excited, and the movable iron core 14 is attracted against the first compression spring 18. Following the rise of the movable iron core 14, the second compression spring 9 extends while pushing up the shaft member 5, and keeps the shaft member 5 in contact with the bottom surface 14b. Accordingly, in the diaphragm 4, the valve body portion 4a rises together with the shaft member 5, and is separated from the valve seat 2c. Therefore, when the solenoid valve 1 is opened, the movable iron core 14 and the diaphragm assembly 3 are integrally raised by a predetermined stroke.

  Thereafter, when energization of the coil 11 is stopped, the movable iron core 14 is urged by the first compression spring 18 and descends. At this time, since the spring force of the first compression spring 18 is larger than the spring force of the second compression spring 9, the movable iron core 14 starts to descend with good responsiveness. The movable iron core 14 descends while pushing down the shaft member 5 at the bottom surface 14b, and brings the valve body portion 4a into contact with the valve seat 2c. When the valve body portion 4 a comes into contact with the valve seat 2 c, the movable iron core 14 is stopped from moving via the shaft member 5. That is, the solenoid valve 1 is in a valve closed state in a state where the diaphragm assembly 3 and the movable iron core 14 are in contact with each other.

  As described above, in the solenoid valve 1, the second compression spring 9 having a smaller urging force than the first compression spring 18 urges the shaft member 5 of the diaphragm assembly 3 in the direction opposite to the first compression spring 18 to move the movable iron core. The diaphragm assembly 3 and the movable iron core 14 are assembled without play so as to be always in contact with 14 (an example of a drive shaft). And also at the time of valve opening and closing operation, the shaft member 5 is always in contact with the movable iron core 14, and the movable iron core 14 and the diaphragm assembly 3 are integrally displaced. Even if the movable core 14 rotates due to the displacement of the movable core 14 or the expansion / contraction of the first compression spring 18 while repeating the valve opening / closing operation, the shaft member 5 is brought into contact with the movable core 14 by the urging force of the second compression spring 9. Since it continues, the stroke does not change. Therefore, according to the connecting structure of the solenoid valve 1 and the diaphragm assembly 3 and the movable iron core 14, it is possible to eliminate variations in strokes between solids.

  Moreover, since the diaphragm 4, the shaft member 5, and the movable iron core 14 move up and down integrally, the solenoid valve 1 should just select the solenoid 10 so that a design stroke may be obtained. Therefore, according to the solenoid valve 1, the solenoid 10 can be reduced in size.

  Moreover, since the electromagnetic valve 1 accommodates the 2nd compression spring 9 attached to the outer peripheral surface of the shaft member 5 in the accommodation hole part 14a of the movable iron core 14, it always makes the diaphragm assembly 3 and the movable iron core 14 contact, restraining total height. The apparatus size can be made compact.

  Further, in the solenoid valve 1, the shaft member 5 protrudes from the solenoid side end face 7 d of the diaphragm holding member 7 to the solenoid 10 side with the diaphragm 4 in contact with the valve seat 2 c, so that the diaphragm assembly 3, The diaphragm holding member 7, the second compression spring 9, and the solenoid 10 can be assembled in this order, and the assemblability is good. That is, the electromagnetic valve 1 places the diaphragm assembly 3 on the valve body 2, then makes the diaphragm holding member 7 abut against the valve body 2 while inserting the shaft member 5 through the boss portion 7 b, and the second compression spring 9 is It is inserted into the shaft member 5 so as to abut against the receiving stepped portion 7e, the retaining ring 8 is attached to the shaft member 5, the second compression spring 9 is fixed, and then the solenoid 10 is placed on the diaphragm holding member 7. If the solenoid 10, the diaphragm assembly 3, and the valve body 2 are fixed by the fixing member, the components in the cover 20 can be assembled.

In addition, this invention is not limited to the said embodiment, Various application is possible.
The connection structure of the diaphragm 4 of the electromagnetic valve 1 and the movable iron core 14 (an example of the drive shaft) of the above embodiment may be applied to the connection structure of the diaphragm of the air operated valve and the drive shaft.
In the said embodiment, although the electromagnetic valve 1 was used for the medical device, it cannot be overemphasized that you may use for another use.
You may comprise the 2nd biasing member by making the 2nd compression spring 9 of the said embodiment into biasing members, such as a leaf | plate spring.

DESCRIPTION OF SYMBOLS 1 Solenoid valve 2 Valve body 2c Valve seat 3 Diaphragm assembly 4 Diaphragm 4c Outer edge part 5 Shaft member 7 Diaphragm holding member 7d Solenoid side end surface 9 2nd compression spring (an example of 2nd biasing member)
DESCRIPTION OF SYMBOLS 10 Solenoid 14 Movable iron core 14a Storage hole 18 1st compression spring (an example of 1st biasing member)

Claims (3)

A valve body provided with a valve seat, a diaphragm assembly in which a shaft member is fixed to a diaphragm that contacts or separates from the valve seat, and an outer edge portion of the diaphragm is held between the valve body and A diaphragm holding member through which the shaft member is inserted, and a solenoid that is in contact with the diaphragm holding member and has a movable iron core biased in a valve seat direction by a first biasing member, together with the movable iron core, the shaft member In an electromagnetic valve that moves the diaphragm to contact or separate the diaphragm from the valve seat,
Having a second urging member having a smaller urging force than the first urging member and constantly urging the diaphragm assembly in the counter valve seat direction ;
The second urging member is a compression spring attached to the outer periphery of the shaft member;
A storage hole portion for storing the shaft member and the second urging member is formed on the end face of the movable iron core on the valve seat side.
Solenoid valve according to claim <br/> be formed. In the solenoid valve according to claim 1 ,
The electromagnetic valve, wherein the shaft member protrudes from a solenoid side end face of the diaphragm holding member toward the solenoid side in a state where the diaphragm is brought into contact with the valve seat. A diaphragm assembly in which a shaft member is fixed to a diaphragm that contacts or separates from the valve seat, and a drive shaft that is urged in the valve seat direction by the first urging member to transmit a driving force to the diaphragm assembly. In the connection structure of assembly and drive shaft,
Having a second urging member having a smaller urging force than the first urging member and constantly urging the diaphragm assembly in the counter valve seat direction;
The second urging member is a compression spring attached to the outer periphery of the shaft member;
A structure for connecting a diaphragm assembly and a drive shaft , wherein a housing hole portion for housing the shaft member and the second urging member is formed on a valve seat side end surface of the drive shaft.

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