JP2020197469A - Device for sealing sealing liquid - Google Patents

Abstract

To provide a device for sealing a sealing liquid which can prevent alteration of a sealing liquid and leakage of the sealing liquid.SOLUTION: The present invention includes: a passage formation member 2 (device body) having a sealing hole 5 (space) having an opening, the sealing hole being filled with a sealing liquid 6; and a sealing material 4 for sealing the opening of the sealing hole 5 by partially melting. The sealing material 4 is in contact with the sealing liquid 6, at least a part of the region in contact with the sealing liquid 6 is not melting, and the sealing liquid 6 is not altered by melting of the sealing material 4.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sealing liquid sealing device.

Examples of the technique related to the sealing device for the encapsulating liquid include the technique described in Patent Document 1 below. In the differential pressure transmitter according to the technique described in Patent Document 1, the oil introduction path is sealed by melting the metal balls arranged in the recess after the oil is poured from the recess of the oil introduction path. ..

Japanese Unexamined Patent Publication No. 2018-159593.

For example, like the differential pressure transmitter described in Patent Document 1, a space filled with an encapsulating liquid (corresponding to the oil introduction path described in Patent Document 1) is provided with a sealing material (metal described in Patent Document 1). When the ball is melted and sealed, the sealing material may be melted while the sealing material is in contact with the sealing liquid. In this case, if the temperature of the encapsulating liquid rises above the heat-resistant temperature, deterioration of the encapsulating liquid may occur, for example, a part of the encapsulating liquid evaporates or air bubbles are mixed in the encapsulating liquid. For example, when the encapsulating liquid is a pressure transmission medium and a part of the encapsulating liquid is vaporized, the pressure changes due to the decrease in volume. Further, for example, when the encapsulating liquid is a pressure transmission medium and air bubbles are mixed in the encapsulating liquid, the pressure cannot be transmitted correctly. On the other hand, if the temperature of the encapsulant is prevented from rising during sealing in order to avoid the influence of such heat, the encapsulant may be insufficiently melted and the encapsulant may leak.

An object of the present invention is to provide an encapsulating liquid sealing device capable of preventing deterioration of the encapsulating liquid and leakage of the encapsulating liquid.

In order to achieve this object, the encapsulant sealing device according to the present invention has an opening and a space for filling the encapsulant, and a part thereof is melted to seal the opening. The sealing material is in contact with the encapsulant, and at least a part of the portion in contact with the encapsulant is not melted, and the encapsulant is melted. The encapsulant is not altered.

In the present invention, in the encapsulant sealing device, the encapsulant has a thermal conductivity such that the temperature of the encapsulant does not rise above the temperature at which the temperature of the encapsulant is altered when the opening is sealed. You may.

In the present invention, in the sealing liquid sealing device, the sealing material may be formed of a single material.

In the present invention, in the encapsulant sealing device, the encapsulant is formed of a plurality of materials having different thermal conductivity, and the material of the portion in contact with the encapsulant is a material having a lower thermal conductivity. There may be.

In the present invention, in the encapsulation liquid sealing device, the encapsulation liquid is oil which is a pressure transmission medium, has a diaphragm which bends under the pressure transmitted by the oil, and is based on the change of the diaphragm. It may further include a detection member for detecting pressure.

The sealing liquid sealing device according to the present invention includes a passage forming member configured to open a sealing hole on a main surface on one end side, and an opening of the sealing hole in a state where the sealing hole is filled with the sealing liquid. The sealing material includes a melt-solidifying portion formed by melting and solidifying a part of the passage forming member located on the one end side, and the sealing hole. The encapsulation portion has an unmelted portion inserted inside, the melt-solidified portion is in close contact with the main surface of the passage forming member, the unmelted portion is in contact with the encapsulant, and the unmelted portion is in contact with the unmelted portion. The liquid has not deteriorated.

In the present invention, in the sealing liquid sealing device, the sealing hole has a recess that opens to the main surface of the passage forming member on one end side, and a hole that opens to the bottom of the recess. The sealing material may have an insertion portion that is inserted into the recess and supported by the passage forming member, and a protruding portion that protrudes from the passage forming member.

In the present invention, in the sealing liquid sealing device, the sealing hole has a recess that opens to the main surface of the passage forming member on one end side, and a hole that opens to the bottom of the recess. The sealing material has an insertion portion that is inserted into the recess and supported by the passage forming member, and a protruding portion that protrudes from the passage forming member so as to overlap the main surface on one end side of the passage forming member. You may be.

In the present invention, in the sealing liquid sealing device, the sealing hole has a recess that opens to the main surface of the one end side of the passage forming member and a hole that opens to the bottom of the recess. The encapsulant is composed of a thermal insulator placed on the bottom of the recess and made of a material having a relatively low thermal conductivity, and a encapsulant body that is superposed on the thermal insulator and projects from the recess. The unmelted portion may be formed by at least a part of the thermal insulator, and the melt-solidified portion may be formed by the sealing material main body.

In the present invention, in the sealing liquid sealing device, two recesses that are communicated with the sealing hole and filled with the filling liquid are formed on the main surface on the other end side of the passage forming member to form the passage. The member constitutes a differential pressure sensor together with a sensor diaphragm that closes the openings of the two recesses and a support member that sandwiches the sensor diaphragm in cooperation with the passage forming member, and the support member comprises the two recesses. Has a pair of pressure chambers facing each other with the sensor diaphragm in between, and pressure on the low pressure side is transmitted to one of the pair of pressure chambers via a pressure transmission medium and to the other pressure chamber. The pressure on the high pressure side may be transmitted via the pressure transmission medium.

According to the present invention, deterioration of the encapsulating liquid and leakage of the encapsulating liquid can be prevented.

It is sectional drawing which shows the structure of the sealing apparatus of the sealing liquid which concerns on this invention. It is sectional drawing which shows the sealing apparatus before sealing. It is sectional drawing of the differential pressure sensor which has the sealing device of the sealing liquid which concerns on this invention. It is sectional drawing of the absolute pressure sensor which has the sealing device of the sealing liquid which concerns on this invention. It is sectional drawing which shows the modification of the sealing hole and the sealing material. It is sectional drawing which shows the modification of the sealing hole and the sealing material. It is sectional drawing which shows the modification of the sealing hole and the sealing material.

(First Embodiment)
Hereinafter, an embodiment of the encapsulation liquid encapsulation device according to the present invention will be described in detail with reference to FIGS. 1 and 2.
The sealing liquid sealing device 1 shown in FIG. 1 is welded to the passage forming member 2 located on the lower side in FIG. 1 and the main surface 3 on one end side (upper side in FIG. 1) of the passage forming member 2. It includes a sealing material 4. The passage forming member 2 constitutes the "device main body" of the present invention, and opens through the main surface 3 on one end side and the main surface (not shown) on the other end side to penetrate the passage forming member 2. It has an encapsulation hole 5. The sealing hole 5 is a space having an opening and filled with the filling liquid 6. As the material for forming the passage forming member 2, metal, glass, silicon or the like can be used, and there is no particular limitation. In this embodiment, a case where the passage forming member 2 is formed of silicon will be described.

The sealing hole 5 has a recess 5a that opens in the main surface 3 on one end side of the passage forming member 2, and a hole 5b that opens in the bottom of the recess 5a. The other end of the hole 5b is closed by a member (not shown). The sealing liquid 6 is filled in the sealing hole 5. The encapsulating liquid 6 is a liquid encapsulating material for the purpose of encapsulation, silicon oil or fluorine oil which is a pressure transmission medium, or the like. When the encapsulating liquid 6 is used as a pressure transmission medium, for example, an oil called KF96, an oil called SH704, an oil called SH705, or the like can be used.

The recess 5a is a hole having a circular opening shape and a depth shallower than the inner diameter. The hole 5b is open to the center of the recess 5a. The wall surface of the recess 5a is covered with the metal film 7. The metal film 7 is formed so as to extend from the inside of the recess 5a onto the main surface 3 on one end side of the passage forming member 2. Although not shown in detail, the metal film 7 is a multi-layered film including a layer bonded to the passage forming member 2 and a layer bonded to the sealing material 4. Such a metal film 7 can be formed by a sputtering method, a vacuum vapor deposition method, or the like.

A part of the sealing material 4 is melted to seal the opening of the sealing hole 5. More specifically, the sealing material 4 is welded to the passage forming member 2 in a state where the sealing hole 5 is filled with the filling liquid 6 to close the opening of the sealing hole 5. The term "welding" as used herein means that a part of the sealing material 4 is melted and spreads wet on the main surface of the passage forming member 2, and the wet and spread melted portion cools and solidifies to form the main passage forming member 2. It is a phenomenon that adheres to the surface. The sealing material 4 is formed of a metal material described later, and has a melt-solidified portion 11 in which a part of the passage forming member 2 located on the main surface side is melted and solidified, and the inside (recessed portion) of the sealing hole 5. It has an unmelted portion 12 inserted into (inside 5a). That is, the sealing material 4 is in contact with the encapsulant 6, and at least a part of the portion in contact with the encapsulant is not melted. Further, the sealing material 4 has a thermal conductivity such that the temperature of the sealing liquid 6 does not rise above the temperature at which the temperature of the sealing liquid 6 is altered when the opening of the sealing hole 5 is sealed. The encapsulant 4 according to this embodiment is made of a single material.

The melt-solidified portion 11 is in close contact with the main surface 3 on one end side of the passage forming member 2 via the metal film 7. When the melt-solidifying portion 11 is in close contact with the passage forming member 2, the encapsulating liquid 6 in the encapsulation hole 5 is sealed. The unmelted portion 12 is located in the recess 5a of the sealing hole 5 and is in contact with the filling liquid 6. There are a plurality of types of metal materials that can be used to form the sealing material 4. Examples of the metal material of the sealing material 4 include Au-20Sn, Au-90Sn, Au-12Ge, Pb-63Sn, and Au. Au-20Sn has a melting point of 280 ° C, Au-90Sn has a melting point of 217 ° C, Au-12Ge has a melting point of 356 ° C, Pb-63Sn has a melting point of 183 ° C, and Au has a melting point of 1063 ° C. Is. The heat resistant temperature of the encapsulant 6 used in this embodiment is lower than the melting point of the encapsulant 4 described above.

The fact that the unmelted portion 12 of the sealing material 4 is in contact with the sealing liquid 6 can prevent the sealing liquid 6 from exceeding the heat resistant temperature in the process of welding the sealing material 4 to the passage forming member 2. Means. Therefore, the encapsulant 6 can be maintained in a state in which the encapsulant 4 is not deteriorated in the process of being welded. That is, the encapsulant 6 has not deteriorated due to the melting of the encapsulant 4. The term "alteration" as used herein means that when the temperature of the encapsulating liquid 6 exceeds the heat resistant temperature, a part of the encapsulating liquid 6 is vaporized or bubbles are generated in the encapsulating liquid 6. When the sealing device 1 is a differential pressure sensor described later or an absolute pressure sensor described later, whether or not the filling liquid 6 is altered in the sealing device 1 is determined by, for example, whether or not the zero point is offset. can do. The method for determining whether or not the filling liquid 6 has deteriorated is not limited to the example shown above. For example, whether or not the encapsulant 6 has been altered may be determined by analyzing the components of the encapsulant 6.

The melt-solidified portion 11 and the unmelted portion 12 of the sealing material 4 can be formed by melting a part of the spherically formed metal balls 13 by laser light and then solidifying them as shown in FIG. it can. By controlling the energy of the laser beam, a part of the metal ball 13 is melted and spreads wet on the main surface 3 of the passage forming member 2, and a part of the metal ball 13 is formed as an unmelted portion 12 in the recess 5a. The remaining semi-molten state can be realized.

The length W (see FIG. 1) of the molten portion that wets and spreads on the passage forming member 2 can be changed according to the adhesion strength required for the sealing material 4. When increasing the adhesion strength of the sealing material 4, the length W of the molten portion is increased. When the adhesion strength of the sealing material 4 may be low, the length W of the molten portion is shortened. The sealing material 4 according to this embodiment is attached to the passage forming member 2 so that the width W of the molten portion is maximized while satisfying the condition that the temperature of the unmelted portion 12 is lower than the heat resistant temperature of the filling liquid 6. It is welded.

In this embodiment, in order to satisfy the condition that the temperature of the unmelted portion 12 is lower than the heat resistant temperature of the filling liquid 6, the main passage forming member 2 is located at the melting limit position shown by the alternate long and short dash line A in FIG. Welding is performed so that the sealing material 4 melts only on the surface 3 side. The melting limit position is a position separated from the filling liquid 6 by a predetermined length on the main surface 3 side of the passage forming member 2.

In the sealing device 1 of the sealing liquid 6 configured in this way, the sealing liquid 6 can be sealed in the sealing hole 5 by the sealing material 4 in which the unmelted portion 12 is in contact with the sealing liquid 6, and the sealing liquid 6 is sealed. The temperature of the encapsulant 6 at that time can be kept low. Therefore, it is possible to provide a sealing liquid sealing device capable of melting the sealing material 4 and sealing the sealing liquid 6 while preventing deterioration of the sealing liquid 6 and leakage of the sealing liquid 6.

The heat resistant temperature of the encapsulant 6 according to this embodiment is lower than the melting point of the encapsulant 4. Therefore, since a general oil having a low heat resistant temperature can be used as the encapsulating liquid 6, it is possible to provide a highly versatile encapsulating liquid sealing device.

(Second Embodiment)
The encapsulation liquid encapsulation device according to the present invention can be used for a differential pressure sensor as shown in FIG. In FIG. 3, the same or equivalent members as those described with reference to FIGS. 1 and 2 are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate. The sealing liquid sealing device according to this embodiment constitutes the invention according to claim 10.

The sealing liquid sealing device 1 shown in FIG. 3 constitutes a part of the differential pressure sensor 21 located at the top in FIG. A first recess 23 and a second recess 24 are formed on the main surface 22 on the other end side (lower side in FIG. 3) of the passage forming member 2 constituting the sealing liquid sealing device 1. .. These first and second recesses 23 and 24 are communicated with each other via a communication passage 25 formed in the passage forming member 2. The communication passage 25 is connected to the hole portion 5b of the sealing hole 5. The first and second recesses 23 and 24, the communication passage 25, and the sealing hole 5 are filled with the filling liquid 6 serving as a pressure transmission medium. The filling liquid 6 is oil which is a pressure transmission medium, and is injected through the filling hole 5. The sealing hole 5 is closed by the sealing material 4 after the filling liquid 6 is injected.

One main surface 26a of the plate-shaped sensor diaphragm 26 that bends in response to the pressure transmitted by the filling liquid 6 (oil) is joined to the main surface 22 on the other end side of the passage forming member 2. The opening portion of the first recess 23 and the opening portion of the second recess 24 of the passage forming member 2 are closed by the sensor diaphragm 26. The sensor diaphragm 26 is formed so as to protrude from the passage forming member 2 in a direction orthogonal to the thickness direction. A bridge circuit 28 for converting the displacement of the sensor diaphragm 26 into an electric signal is provided in a portion of the sensor diaphragm 26 facing the first recess 23 and a portion facing the second recess 24, respectively. These bridge circuits 28 constitute a detection member that detects pressure based on a change in the sensor diaphragm 26. Further, these bridge circuits 28 are connected to electrode pads 27 provided on the side portions of the sensor diaphragm 26.

One main surface 31a of the support member 31 is joined to the other main surface 26b (lower side in FIG. 3) of the sensor diaphragm 26. The sensor diaphragm 26 and the support member 31 are each formed of silicon into a predetermined shape. The support member 31 sandwiches and supports the sensor diaphragm 26 in cooperation with the passage forming member 2. The differential pressure sensor 21 according to this embodiment is composed of a passage forming member 2, a sensor diaphragm 26, a support member 31, and the like. Further, the differential pressure sensor 21 is mounted on the diaphragm base 34 of the differential pressure transmitter 33 via an insulating member 32 described later.

The support member 31 of the differential pressure sensor 21 has a pair of pressure chambers 35 and 36 facing the first and second recesses 23 and 24 of the passage forming member 2 with the sensor diaphragm 26 interposed therebetween. Each of these pressure chambers 35 and 36 has a support member 31 opened to one main surface 31a and the other main surface 31b, and is formed by being surrounded by the support member 31, the sensor diaphragm 26, and the insulating member 32. Has been done. The support member 31 is joined to one main surface 32a of the insulating member 32.

The insulating member 32 is made of glass and electrically insulates the differential pressure sensor 21 and the diaphragm base 34. The other main surface 32b of the insulating member 32 is adhered to one main surface 34a of the diaphragm base 34 by an adhesive 37. The insulating member 32 is formed with a first through hole 38 that opens into one pressure chamber 35 of the support member 31 and a second through hole 39 that opens into the other pressure chamber 36 of the support member 31. ..

The diaphragm base 34 is formed in a predetermined shape by a metal material such as stainless steel. A relay board 41 is provided on one main surface 34a of the diaphragm base 34 so as to be adjacent to the differential pressure sensor 21. The relay board 41 is provided with an electrode pad 42 and a plurality of external output pins (not shown). The electrode pad 42 is connected to the external output pin by a wiring (not shown). Further, the electrode pad 42 is connected to the electrode pad 27 of the sensor diaphragm 26 via a bonding wire 43. As a result, the differential pressure sensor 21 uses the electrode pad 27 on the sensor diaphragm 26 side, the bonding wire 43, the electrode pad 42 on the relay board 41 side, a signal processing circuit and a power supply (not shown) via an external output pin or the like. It is electrically connected to other circuits such as circuits.

On the other main surface 34b of the diaphragm base 34 (lower side in FIG. 3), a first pressure receiving chamber 44 and a second pressure receiving chamber 45 formed of recesses that open in the direction opposite to the insulating member 32 are formed. Has been done. The opening of the first pressure receiving chamber 44 is closed by the first barrier diaphragm 46. The opening of the second pressure receiving chamber 45 is closed by the second barrier diaphragm 47. Although not shown, the first barrier diaphragm 46 is configured to be a part of the wall of the low-pressure side fluid passage through which the fluid to be measured flows, and is joined to the diaphragm base 34. The second barrier diaphragm is configured to be a part of the wall of the high-pressure side fluid passage through which the fluid to be measured flows, and is joined to the diaphragm base 34.

Further, the diaphragm base 34 has a third through hole 48 that communicates the first through hole 38 of the insulating member 32 and the first pressure receiving chamber 44, and the second through hole 39 and the second through hole 39 of the insulating member 32. A fourth through hole 49 is formed which communicates with the pressure receiving chamber 45 of the above. The first pressure receiving chamber 44, the third through hole 48, the first through hole 38, and one pressure chamber 35 of the support member 31 use the pressure applied to the first barrier diaphragm 46 as a sensor diaphragm. A first pressure guiding path 51 that transmits to 26 is formed, and is filled with oil 52 as a pressure transmitting medium. The oil 52 is injected into the first pressure receiving chamber 44 through the first oil introduction hole 53 provided on one side of the diaphragm base 34. The first oil introduction hole 53 is closed by the first plug member 54 after the oil is injected.

Further, the second pressure receiving chamber 45, the fourth through hole 49, the second through hole 39, and the other pressure chamber 36 of the insulating member 32 apply the pressure applied to the second barrier diaphragm 47. A second pressure guiding path 55 that transmits to the sensor diaphragm 26 is formed, and is filled with oil 52 as a pressure transmitting medium as in the first pressure guiding path 51. The oil 52 in the second pressure guiding path 55 is injected into the second pressure receiving chamber 45 through the second oil introduction hole 56 provided on the other side of the diaphragm base 34. The second oil introduction hole 56 is closed by the second plug member 57 after the oil is injected.

In the differential pressure transmitter 33 configured in this way, the pressure of the fluid to be measured applied to the first barrier diaphragm 46 is transmitted to one pressure chamber 35 of the support member 31 via the oil 52. Further, the pressure of the fluid to be measured applied to the second barrier diaphragm 47 is transmitted to the other pressure chamber 36 of the support member 31 via the oil 52. As the pressure is transmitted to one pressure chamber 35 and the other pressure chamber 36 in this way, the sensor diaphragm 26 is displaced, and the differential pressure is detected by the differential pressure sensor 21.

The sealing device 1 for the filling liquid 6 shown in FIG. 3 seals the filling liquid 6 that transmits pressure between the inside of the first recess 23 and the inside of the second recess 24 of the differential pressure sensor 21. .. Therefore, by using this sealing device 1, a differential pressure sensor 21 in which the filling liquid 6 in the passage forming member 2 is not deteriorated can be obtained. The presence or absence of deterioration of the encapsulant 6 can be determined by whether or not the 0 point of the differential pressure sensor 21 changes between before and after welding the encapsulant 4.

When the encapsulant 6 is vaporized due to alteration, the 0 point of the differential pressure sensor 21 changes because the volume of the encapsulant 6 decreases. Further, when the filling liquid 6 is altered in quality, bubbles may be generated. Whether or not bubbles are generated in the filling liquid 6 can be determined by whether or not the 0 point of the differential pressure sensor 21 changes while the periphery of the differential pressure sensor 21 is evacuated. When air bubbles are mixed in the encapsulating liquid 6, the 0 point of the differential pressure sensor 21 changes because the surroundings become a vacuum and the air bubbles expand and the encapsulating liquid 6 is pressed. Further, the strength of the sealing device 1, that is, the bonding strength of the sealing material 4, can be inspected by applying a static pressure to the sealing liquid 6.
Therefore, according to this embodiment, it is possible to realize a sealing liquid sealing device in which the influence on the sensor characteristics of the differential pressure sensor 21 can be ignored.

(Third Embodiment)
The sealing liquid sealing device according to the present invention can be used for an absolute pressure sensor as shown in FIG. In FIG. 4, the same or equivalent members as those described with reference to FIGS. 1 and 2 are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate. The sealing liquid sealing device 1 shown in FIG. 4 constitutes a part of the absolute pressure sensor 61 located at the top in FIG.

The absolute pressure sensor 61 is overlapped with the passage forming member 2 forming a part of the sealing device 1 of the encapsulating liquid 6 on the other end side of the passage forming member 2 so that the passage forming member 2 is located at one end. It is composed of four members. The four members are a sensor diaphragm 62 joined to the main surface 22 on the other end side (lower side in FIG. 4) of the passage forming member 2, an intermediate member 63 joined to the sensor diaphragm 62, and an intermediate member 63. It is a support member 64 joined to. The passage forming member 2, the sensor diaphragm 62, the intermediate member 63, and the support member 64 are each made of silicon. Further, the absolute pressure sensor 61 is supported by the diaphragm base 67 of the absolute pressure transmitter 66 via a glass insulating member 65.

A pressure chamber 71 formed of a recess is formed on the main surface 22 on the other end side of the passage forming member 2. The opening portion of the pressure chamber 71 is closed by the sensor diaphragm 62. Further, the pressure chamber 71 is connected to the sealing hole 5 via the communication hole 72. The sealing hole 5 is formed so as to penetrate the passage forming member 2 from one end side (upper side in FIG. 4) to the other end side.

A bridge circuit (not shown) that converts the displacement of the sensor diaphragm 62 into an electric signal is provided at a portion of the sensor diaphragm 62 facing the pressure chamber 71. Although not shown, this bridge circuit is electrically connected to other circuits such as a signal processing circuit and a power supply circuit of the absolute pressure transmitter 66. The sensor diaphragm 62 according to this embodiment is formed with a first through hole 73 connected to the sealing hole 5 of the passage forming member 2. The first through hole 73 is formed so as to penetrate the sensor diaphragm 62 from one end to the other end in the thickness direction.

The intermediate member 63 cooperates with the passage forming member 2 to support the sensor diaphragm 62. In the intermediate member 63, a second through hole 74 having a relatively large opening diameter and a third through hole 75 having a relatively small opening diameter penetrate the intermediate member 63 from one end side to the other end side, respectively. It is formed like this. The opening on one end side of the second through hole 74 is closed by the sensor diaphragm 62, and the opening on the other end side is closed by the support member 64. The inside of the second through hole 74 is hermetically sealed in a vacuum state. The third through hole 75 is formed at a position connected to the first through hole 73 of the sensor diaphragm 62.

The support member 64 is formed with a fourth through hole 76 connected to the third through hole 75 of the intermediate member 63. The fourth through hole 76 is formed so as to penetrate the support member 64 from one end side to the other end side.
The insulating member 65 is formed with a fifth through hole 77 connected to the fourth through hole 76 of the support member 64. The fifth through hole 77 is formed so as to penetrate the insulating member 65 from one end side to the other end side. The insulating member 65 is adhered to the main surface 67a on one end side of the diaphragm base 67 by an adhesive 78.

The diaphragm base 67 is formed of a metal material such as stainless steel into a predetermined shape, and has a pressure receiving chamber 81 formed of a recess opening in the main surface 67b on the other end side and a sixth opening in the bottom of the pressure receiving chamber 81. Through hole 82 is formed. The opening portion of the pressure receiving chamber 81 is closed by the barrier diaphragm 83. The barrier diaphragm 83 forms a part of the wall of the fluid passage through which the fluid to be measured (not shown) flows, and is joined to the diaphragm base 67.

The sixth through hole 82 is formed so as to penetrate the diaphragm base 67 from one end side to the other end side, and is connected to the fifth through hole 77 of the insulating member 65.
The sealing hole 5 of the passage forming member 2, the communication hole 72 and the pressure chamber 71, the first through hole 73, the third through hole 75, the fourth through hole 76, and the fifth through hole 77. The pressure receiving chamber 81 and the sixth through hole 82 form a pressure guiding passage 84 that transmits the pressure applied to the barrier diaphragm 83 to the sensor diaphragm 62, and is filled with oil 85 as a pressure transmitting medium.

The sealing liquid sealing device 1 shown in FIG. 4 seals the oil 85 that transmits pressure between the sensor diaphragm 62 of the absolute pressure sensor 61 and the barrier diaphragm 83. Therefore, by using this sealing device 1, an absolute pressure transmitter 66 in which the oil 85 is not deteriorated can be obtained.

In the absolute pressure transmitter 66 according to this embodiment, an injection port for injecting oil 85 (filling liquid) into the pressure guiding path 84 from the pressure receiving chamber 81 of the diaphragm base 67 to the pressure chamber 71 of the passage forming member 2 is provided. There is only one place in the sealing hole 5. Therefore, as compared with the case where the diaphragm base 67 is provided with the lubrication portion including the lubrication passage, the volume of the pressure guiding path filled with the oil 85 can be reduced as much as possible, and the amount of the oil 85 can be reduced. Can be done. As a result, the amount of expansion and contraction of the oil 85 due to the temperature change is reduced, and the load on the barrier diaphragm 83 can be reduced. Further, since the barrier diaphragm 83 can be miniaturized, the absolute pressure transmitter 66 can be miniaturized.

(Fourth Embodiment)
The sealing liquid sealing device according to the present invention can be configured as shown in FIGS. 5 to 7. In these figures, the same or equivalent members as those described with reference to FIGS. 1 and 2 are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate. The encapsulating liquid sealing device 1 shown in FIG. 5 constitutes the invention according to claim 7, and the encapsulating liquid sealing device 1 shown in FIG. 6 constitutes the invention according to claim 8. It is a thing. The sealing liquid sealing device 1 shown in FIG. 7 constitutes the invention according to claim 9. 5 and 7 show a state before the sealing material 4 is welded to the passage forming member 2.

The sealing holes 5 shown in FIGS. 5 to 7 have a recess 5a that opens in the main surface 3 on one end side of the passage forming member 2 and a hole 5b that opens in the bottom of the recess 5a. The opening shape of the recess 5a is a circle, a quadrangle, a triangle, or the like. Further, as shown in FIGS. 5 to 7, the recess 5a has a rectangular cross-sectional shape when viewed from a direction orthogonal to the main surface 3 of the passage forming member 2 (direction perpendicular to the paper surface of FIGS. 5 to 7). It is formed like this.

The sealing material 4 before welding shown in FIG. 5 has an insertion portion 91 inserted into the recess 5a of the sealing hole 5 and supported by the passage forming member 2, and a protruding portion 92 protruding from the passage forming member 2. There is. The protruding portion 92 according to this embodiment is formed in a columnar shape in which the insertion portion 91 is extended to the side opposite to the recess 5a. In a state where the sealing material 4 is welded to the passage forming member 2, the insertion portion 91 becomes an unmelted portion 12 as shown in FIG. 1, and the protruding portion 92 becomes a melt-solidified portion 11 as shown in FIG. ..

By adopting the configuration shown in FIG. 5, since the support of the sealing material 4 is stabilized before welding, welding can be performed more reliably. Further, since it is difficult for a gap to be formed between the recess 5a and the sealing material 4, the sealing material 4 is firmly fixed to the passage forming member 2.

The sealing material 4 before welding shown in FIG. 6 overlaps the insertion portion 93 inserted into the recess 5a of the sealing hole 5 and supported by the passage forming member 2 and the main surface 3 on one end side of the passage forming member 2. It has a protruding portion 94 protruding from the passage forming member 2. The protruding portion 94 has a flat surface 94a that overlaps with the main surface 3 on one end side of the passage forming member 2. In the state where the sealing material 4 is welded to the passage forming member 2, the insertion portion 93 becomes the unmelted portion 12 as shown in FIG. 1, and the protruding portion 94 becomes the melt-solidified portion 11 as shown in FIG. ..

By adopting the configuration shown in FIG. 6, since the sealing material 4 can be welded to the passage forming member 2 by melting the outer edge portion of the protruding portion 94, the sealing material 4 is transmitted to the filling liquid via the inserting portion 93. The heat can be reduced as much as possible. Therefore, it is possible to secure a wider welding area and increase the welding strength.

The sealing material 4 before welding shown in FIG. 7 is formed of a plurality of materials having different thermal conductivity. That is, the sealing material 4 shown in FIG. 7 is placed on the bottom of the recess 5a and closes the hole 5b with a thermal insulator 95 having a relatively low thermal conductivity, and the recess 95 is overlapped with the thermal insulator 95. It is composed of a columnar sealing material main body 96 protruding from 5a. In the sealing material 4 according to this embodiment, the material of the portion in contact with the sealing liquid is a material having a lower thermal conductivity. The thermal insulator 95 is formed in a shape that can be inserted into the recess 5a. The melting point of the thermal insulator 95 is relatively high, and the melting point of the sealing material body 96 is relatively low. The thermal insulator 95 can be formed of a metal, a heat-resistant plastic material, or the like. In a state where the sealing material 4 is welded to the passage forming member 2, the sealing material main body 96 becomes a melt-solidified portion 11 as shown in FIG. In this welding process, the thermal insulator 95 can be realized in a state where the sealing material main body 96 is melted and the thermal insulator 95 is not melted, so that the heat transferred to the encapsulant is blocked by the thermal insulator 95. Become. Therefore, the filling liquid can be more reliably maintained at a temperature lower than the heat resistant temperature.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings. However, the technical scope of the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the technical field of the present invention can come up with various modifications within the scope of the technical idea described in the claims, and these modifications Of course, also belongs to the technical scope of the present invention.

1 ... Sealing liquid sealing device, 2 ... Passage forming member, 3 ... Main surface on one end side, 4 ... Sealing material, 5 ... Sealing hole, 5a ... Recessed portion, 5b ... Hole, 6 ... Encapsulating liquid, 11 ... Melt solidification part, 12 ... unmelted part, 21 ... differential pressure sensor, 26 ... sensor diaphragm, 28 ... bridge circuit, ... 31 ... support member, 91, 93 ... insertion part, 92, 94 ... protrusion, 95 ... thermal insulation Body, 96 ... Encapsulant body.

Claims (10)

The main body of the device, which has an opening and a space for filling the encapsulant,
A sealing material that partially melts to seal the opening,
With
The sealing material is
It is contacted with the encapsulant
At least a part of the portion that comes into contact with the filling liquid is not melted.
An encapsulation liquid encapsulation device in which the encapsulant is not altered by melting of the encapsulant. The encapsulant encapsulant according to claim 1, wherein the encapsulant has a thermal conductivity such that the temperature of the encapsulant does not rise above the temperature at which the encapsulant changes in quality when the opening is sealed. The encapsulant encapsulant according to claim 1 or 2, wherein the encapsulant is made of a single material. The sealing material is
Formed from multiple materials with different thermal conductivity,
The encapsulation liquid encapsulation device according to claim 1 or 2, wherein the material of the portion that comes into contact with the encapsulant is a material having a lower thermal conductivity. The filling liquid is an oil that is a pressure transfer medium.
The encapsulant according to any one of claims 1 to 4, further comprising a detection member having a diaphragm that bends in response to the pressure transmitted by the oil and detecting the pressure based on the change in the diaphragm. Sealing device. A passage forming member configured to have an encapsulation hole on the main surface on one end side,
A sealing material configured to close the opening of the sealing hole in a state where the sealing hole is filled with the sealing liquid is provided.
The sealing material is
A melt-solidified portion formed by melting and solidifying a part of the passage forming member located on the one end side.
It has an unmelted portion inserted inside the sealing hole, and has an unmelted portion.
The melt-solidified portion is in close contact with the main surface of the passage forming member.
The unmelted portion comes into contact with the filling liquid,
An encapsulating liquid sealing device in which the encapsulating liquid in contact with the unmelted portion has not deteriorated. The sealing hole has a recess that opens to the main surface of the passage forming member on one end side, and a hole that opens to the bottom of the recess.
The sealing liquid sealing device according to claim 6, wherein the sealing material has an insertion portion inserted into the recess and supported by the passage forming member, and a protruding portion protruding from the passage forming member. .. The sealing hole has a recess that opens to the main surface of the passage forming member on one end side, and a hole that opens to the bottom of the recess.
The sealing material has an insertion portion that is inserted into the recess and supported by the passage forming member, and a protruding portion that protrudes from the passage forming member so as to overlap the main surface of the passage forming member on one end side. The sealing device for an encapsulating liquid according to claim 6. The sealing hole has a recess that opens to the main surface of the passage forming member on one end side, and a hole that opens to the bottom of the recess.
The sealing material is
A thermal insulator placed on the bottom of the recess and made of a material having a relatively low thermal conductivity,
It is composed of a sealing material main body that is superposed on the thermal insulator and projects from the recess.
The unmelted portion is formed by at least a part of the thermal insulator.
The encapsulant sealing device according to claim 6, wherein the melt-solidified portion is formed by the encapsulant main body. On the main surface on the other end side of the passage forming member, two recesses are formed which are communicated with the sealing hole and filled with the filling liquid.
The passage forming member is
A sensor diaphragm that closes the openings of the two recesses,
A differential pressure sensor is configured together with a support member that sandwiches the sensor diaphragm in cooperation with the passage forming member.
The support member has a pair of pressure chambers facing each other with the sensor diaphragm interposed therebetween in the two recesses.
Claim that the pressure on the low pressure side is transmitted to one of the pair of pressure chambers via the pressure transmission medium, and the pressure on the high pressure side is transmitted to the other pressure chamber via the pressure transmission medium. 6. The apparatus for sealing an encapsulating liquid according to any one of claims 9.

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