Gauge pressure core

Abstract

The invention relates to the field of pressure sensors, in particular to a gauge pressure core which comprises a shell, a first chip, a second chip, a first diaphragm, a second diaphragm and silicone oil. The shell is made of a metal material and is configured into a first section and a second section, the first section is concavely provided with a first mounting cavity, the second section is concavely provided with a second mounting cavity, the first chip is arranged in the first mounting cavity, and the second chip is arranged in the second mounting cavity; the first diaphragm covers the first mounting cavity, the second diaphragm covers the second mounting cavity, and the first mounting cavity and the second mounting cavity are configured to be isolated from each other. On the basis that an air hole in the prior art is omitted, the pressure of a detected medium is obtained through the first diaphragm, and the atmospheric pressure is obtained through the second diaphragm; the atmospheric pressure enables the second diaphragm to deform along the direction from the second diaphragm to the first diaphragm, so that the atmospheric pressure extrudes the silicone oil in the second mounting cavity through the second diaphragm to be transmitted to the second chip.

Description

Technical Field

[0001] The invention relates to the field of pressure sensors, in particular to a gauge pressure core. Background Art

[0002] The gauge pressure sensor in the prior art is usually provided with an air hole. For example, the patent document with application number 202211719967.6 and invention name is a ventilated gauge pressure sensor. The patent document specifically proposes a gauge pressure sensor, and the pressure core of the gauge pressure sensor is provided with an air hole.

[0003] In a pressure core with pores, the atmospheric pressure outside the pressure core is introduced into the interior of the pressure core through the pores, so that the atmospheric pressure acts on the pressure chip. Under this setting, water vapor can adhere to the pressure chip. If this pressure core is used for a long time, the water vapor condenses into water and corrodes the pressure chip, or causes the adhesive of the pressure chip to crack, causing the pressure core of the gauge pressure sensor to fail.

[0004] The inventor of this case proposed a gauge pressure core without the air hole; however, under the condition of eliminating the air hole, how the gauge pressure core can detect the atmospheric pressure becomes a technical problem to be solved. Summary of the invention

[0005] In order to solve the technical problem of how the gauge pressure core detects the atmospheric pressure after the air hole is eliminated, the present invention provides a gauge pressure core.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is:

[0007] According to one aspect of the present invention, there is provided a gauge pressure core, comprising a housing, a first chip, a second chip, a first diaphragm, a second diaphragm and silicone oil;

[0008] The shell is made of metal material, and is configured into a first section and a second section, the first section and the second section are respectively configured as a cylinder, the diameter of the first section is greater than the diameter of the second section, and the first section and the second section are coaxial and integrally manufactured;

[0009] Along the direction from the first section to the second section, the first section is recessed to form a first mounting cavity, and along the direction from the second section to the first section, the second section is recessed to form a second mounting cavity, the first chip is disposed in the first mounting cavity, and the second chip is disposed in the second mounting cavity;

[0010] The first diaphragm covers the first installation cavity, the second diaphragm covers the second installation cavity, and the first installation cavity and the second installation cavity are configured to be isolated from each other.

[0011] Furthermore, it also includes a first oil injection channel and a second oil injection channel, wherein the first oil injection channel is used to connect the first installation cavity and the atmosphere, and the second oil injection channel is used to connect the second installation cavity and the atmosphere, and the silicone oil is configured to be injected into the first installation cavity through the first oil injection channel, and the silicone oil is configured to be injected into the second installation cavity through the second oil injection channel.

[0012] It also includes a sealing ball, which is made of metal material;

[0013] The first oil injection channel and the surface of the first section form a first oil injection hole, and the first oil injection hole is covered by the first sealing ball, wherein the gap between the first sealing ball and the first section is defined as a first gap, and the first gap forms a first sealing structure by welding the first sealing ball and the first section;

[0014] The second oil injection channel and the surface of the first section form a second oil injection hole, and the second oil injection hole is covered by the second sealing ball, wherein the gap between the second sealing ball and the first section is defined as a second gap, and the second gap forms a second sealing structure by welding the second sealing ball to the first section.

[0015] Furthermore, the end faces of the two axial ends of the first section are respectively a first end face and a second end face, and the second section is located at the second end face;

[0016] The first oil filling hole is located on the second end surface;

[0017] The second oil filling hole is located on the circumferential surface of the second section.

[0018] Furthermore, it also includes a first chip base and a second chip base;

[0019] The first chip base is arranged in the first mounting cavity, the second chip base is arranged in the second mounting cavity, and the first chip base and the second chip base are respectively made of ceramic materials;

[0020] The first oil injection channel passes through the first chip base, and the second oil injection channel passes through the second chip base;

[0021] The first chip is bonded to the first chip base, and the second chip is bonded to the second chip base.

[0022] Furthermore, it also includes a first Kovar alloy pin, a second Kovar alloy pin and a third Kovar alloy pin;

[0023] The housing is provided with a first channel, a second channel and a third channel, wherein the first channel and the second channel are respectively located in the first section, the first channel and the second channel are respectively used to connect the first installation cavity and the atmosphere, the third channel passes through the first section and the second section, and the third channel connects the first installation cavity and the second installation cavity respectively;

[0024] Each of the first channels is respectively used to be provided with a first Kovar alloy pin, wherein one end of each of the first Kovar alloy pins is located in the first mounting cavity, and the other end of each of the first Kovar alloy pins is located outside the housing;

[0025] Any of the second channels is respectively used to be provided with a second Kovar alloy pin, wherein one end of any of the second Kovar alloy pins is located in the first mounting cavity, and the other end of any of the second Kovar alloy pins is located outside the housing;

[0026] Each of the third channels is used to be provided with a third Kovar alloy pin, wherein one end of each of the third Kovar alloy pins is located in the first mounting cavity, and the other end of each of the third Kovar alloy pins is located in the second mounting cavity;

[0027] The first chip is electrically connected to the first Kovar alloy pin through a gold wire bonding process;

[0028] The second chip is electrically connected to the third Kovar pin through a gold wire bonding process, and the third Kovar corner is electrically connected to the second Kovar pin through a gold wire bonding process.

[0029] Further, the first chip base is provided with a first through hole, a second through hole and a third through hole;

[0030] The second chip base is provided with a fourth through hole;

[0031] The number of the first through holes is the same as the number of the first channels, and any one of the first Kovar alloy pins passes through one of the first through holes;

[0032] The number of the second through holes is the same as the number of the second channels, and any one of the second Kovar alloy pins passes through one of the second through holes;

[0033] The number of the third through holes and the number of the fourth through holes are respectively the same as the number of the third channels, and any one of the third Kovar alloy pins passes through one of the third through holes and one of the fourth through holes respectively.

[0034] Furthermore, it also includes a first pressure ring and a second pressure ring;

[0035] The first pressing ring and the second pressing ring are respectively made of metal materials;

[0036] The first diaphragm is arranged between the first pressure ring and the first section, and the first pressure ring, the first diaphragm and the first section are welded together;

[0037] The second diaphragm is arranged between the second pressure ring and the second section, and the second pressure ring, the second diaphragm and the second section are welded into one.

[0038] The above technical solution has the following advantages or beneficial effects:

[0039] The gauge pressure core provided by the present invention eliminates the pores in the prior art, thereby preventing water vapor in the atmosphere from flowing into the interior of the gauge pressure core; on this basis, the gauge pressure core provided by the present invention obtains the pressure of the medium to be detected through the first diaphragm, and obtains the atmospheric pressure through the second diaphragm; the atmospheric pressure causes the second diaphragm to deform along the direction from the second diaphragm to the first diaphragm, so that the atmospheric pressure squeezes the silicone oil in the second mounting cavity through the second diaphragm and is transmitted to the second chip, thereby solving the technical problem of how the gauge pressure core can detect the atmospheric pressure under the condition of eliminating the pores. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of the structure of a gauge pressure core provided in Example 1 of the present invention;

[0041] Figure 2 A schematic diagram of the structure of a gauge pressure core provided in Example 1 of the present invention;

[0042] Figure 3 A schematic diagram of the split structure of the gauge pressure core provided in Example 1 of the present invention;

[0043] Figure 4 A schematic diagram of the structure of a gauge pressure core provided in Example 1 of the present invention;

[0044] Figure 5 A schematic diagram of the structure of a gauge pressure core provided in Example 1 of the present invention;

[0045] Figure 6 A cross-sectional view of a gauge pressure core provided in Example 1 of the present invention;

[0046] Figure 7 A cross-sectional view of a housing provided in Embodiment 1 of the present invention;

[0047] Figure 8 A cross-sectional view of a housing provided in Embodiment 1 of the present invention;

[0048] Fig. 9 A cross-sectional view of a shell provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0049] Embodiment 1:

[0050] In order to solve the technical problem in the prior art of how to prevent water vapor from entering into the interior of a gauge pressure sensor and contacting a pressure chip, the present invention provides a gauge pressure core.

[0051] For details, see Figure 1 , Figure 2 or Figure 6 The gauge pressure core of this embodiment includes a housing 1, a first chip 2, a second chip 3, a first diaphragm 4, a second diaphragm 5 and silicone oil 6;

[0052] The housing 1 is made of metal material, and is configured into a first section 11 and a second section 12. The first section 11 and the second section 12 are respectively configured in a cylindrical shape. The diameter of the first section 11 is greater than the diameter of the second section 12. The first section 11 and the second section 12 are coaxial and integrally manufactured.

[0053] Along the direction from the first section 11 to the second section 12, the first section 11 is recessed to form a first mounting cavity 111, and along the direction from the second section 12 to the first section 11, the second section 12 is recessed to form a second mounting cavity 121. The first chip 2 is disposed in the first mounting cavity 111, and the second chip 3 is disposed in the second mounting cavity 121.

[0054] The first diaphragm 4 covers the first installation cavity 111 , the second diaphragm 5 covers the second installation cavity 121 , and the first installation cavity 111 and the second installation cavity 121 are configured to be isolated from each other.

[0055] In this embodiment, see Figure 6 or Figure 8 , the first mounting cavity 111 in the housing 1 is used to accommodate the first chip 2, and the second mounting cavity 121 in the housing 1 is used to accommodate the second chip 3; the first diaphragm 4 covers the first mounting cavity 111, so that the first chip 2 is confined between the housing 1 and the first diaphragm 4. In other words, the first diaphragm 4 isolates the first mounting cavity 111 from the atmosphere; similarly, the second diaphragm 5 covers the second mounting cavity 121, so that the second chip 3 is confined between the housing 1 and the second diaphragm 5. In other words, the second diaphragm 5 isolates the second mounting cavity 121 from the atmosphere;

[0056] Under the condition that the first mounting cavity 111 is isolated from the atmosphere by the first diaphragm 4, and under the condition that the second mounting cavity 121 is isolated from the atmosphere by the second diaphragm 5, water vapor in the atmosphere cannot enter the first mounting cavity 111 along the direction from the first diaphragm 4 to the first mounting cavity 111, so that water vapor in the atmosphere cannot contact the first chip 2 in the first mounting cavity 111, and water vapor in the atmosphere cannot enter the second mounting cavity 121 along the direction from the second diaphragm 5 to the second mounting cavity 121, so that water vapor in the atmosphere cannot contact the second chip 3 in the second mounting cavity 121.

[0057] The first diaphragm 4 is welded to the housing 1; for details, see Figures 1 to 3 , the gauge pressure core of the present embodiment also includes a first pressure ring 21; the first pressure ring 21 is made of metal material, and the first diaphragm 4 is made of metal or alloy material, which is common knowledge known to those skilled in the art; when positioning the first diaphragm 4, the first diaphragm 4 is confined between the shell 1 and the first pressure ring 21, one side of the first diaphragm 4 contacts the shell 1, and the other side of the first diaphragm 4 contacts the first pressure ring 21, at this time, the first diaphragm 4 covers the first installation cavity 111; the shell 1, the first diaphragm 4 and the first pressure ring 21 are welded, and the welding position covers the gap between the shell 1 and the first diaphragm 4, and the gap between the first diaphragm 4 and the first pressure ring 21; from the perspective of a person, a circular ring-shaped welding structure is formed on the shell 1 after the welding is completed, and the welding structure at least seals the gap between the first diaphragm 4 and the shell 1, thereby preventing water vapor from flowing into the first installation cavity 111 through the gap between the first diaphragm 4 and the shell 1.

[0058] Similarly, the second diaphragm 5 is welded to the housing 1; for details, see Figures 1 to 3 The gauge pressure core of the present embodiment further includes a second pressure ring 22; the second pressure ring 22 is made of metal material, and the second diaphragm 5 is made of metal or alloy material, which is common knowledge known to those skilled in the art; when positioning the second diaphragm 5, the second diaphragm 5 is confined between the shell 1 and the second pressure ring 22, one side of the second diaphragm contacts the shell 1, and the other side of the second diaphragm 5 contacts the second pressure ring 22, at this time, the second diaphragm 5 covers the second installation cavity 121; the shell 1, the second diaphragm 5 and the second pressure ring 22 are welded, and the welding position covers the gap between the shell 1 and the second diaphragm 5, and the gap between the second diaphragm 5 and the second pressure ring 22; from the perspective of a person, a circular ring-shaped welding structure is formed on the shell 1 after the welding is completed, and the welding structure at least seals the gap between the second diaphragm 5 and the shell 1, thereby preventing water vapor from flowing into the second installation cavity 121 through the gap between the second diaphragm 5 and the shell 1.

[0059] In the prior art, the pressure core of the gauge pressure sensor is provided with an air hole for connecting to the atmosphere, so that water vapor in the atmosphere can flow into the interior of the pressure core of the gauge pressure sensor. The water vapor adheres to the surface of the chip, so that the condensed water formed by the water vapor corrodes the chip, or the condensed water causes the adhesive of the pressure chip to crack.

[0060] The gauge pressure core in the present embodiment eliminates the pores in the prior art, thereby preventing water vapor in the atmosphere from flowing into the interior of the gauge pressure core. On this basis, the gauge pressure core in the present embodiment obtains the pressure of the medium to be detected through the first diaphragm 4 and obtains the atmospheric pressure through the second diaphragm 5. The atmospheric pressure causes the second diaphragm 5 to deform along the direction from the second diaphragm 5 to the first diaphragm 4, so that the atmospheric pressure is transmitted to the second chip 3 by squeezing the silicone oil 6 in the second mounting cavity 121 through the second diaphragm 5, thereby solving the technical problem of how the gauge pressure core can detect the atmospheric pressure when the pores are eliminated.

[0061] For further information, see Figure 6 The gauge pressure core in this embodiment further includes a first oil injection channel 112 and a second oil injection channel 122, wherein the first oil injection channel 112 is used to connect the first installation cavity 111 with the atmosphere, and the second oil injection channel 122 is used to connect the second installation cavity 121 with the atmosphere, and the silicone oil 6 is configured to be injected into the first installation cavity 111 through the first oil injection channel 112, and the silicone oil 6 is configured to be injected into the second installation cavity 121 through the second oil injection channel 122;

[0062] It also includes a sealing ball 7, which is made of metal material;

[0063] The first oil injection channel 112 and the surface of the first section 11 form a first oil injection hole, and the first oil injection hole is covered by the first sealing ball 7, wherein the gap between the first sealing ball 7 and the first section 11 is defined as a first gap, and the first gap forms a first sealing structure by welding the first sealing ball 7 and the first section 11;

[0064] The second oil injection channel 122 and the circumferential surface of the second section 12 form a second oil injection hole, and the second oil injection hole is covered by the second sealing ball 7, wherein the gap between the second sealing ball 7 and the second section 12 is defined as a second gap, and the second gap forms a second sealing structure by welding the second sealing ball 7 and the second section 12.

[0065] In this embodiment, the first installation cavity 111 is connected to the atmosphere through the first oil injection channel 112; the purpose is to inject silicone oil 6 into the first installation cavity 111 through the first oil injection channel 112 after the first diaphragm 4 covers the first installation cavity 111; after the silicone oil 6 is injected into the first installation cavity 111, when the first diaphragm 4 receives the atmospheric pressure or the medium pressure, the first diaphragm 4 generates a deformation along the direction from the first diaphragm 4 to the first installation cavity 111, and the first diaphragm 4 squeezes the silicone oil 6 in the first installation cavity 111 through the deformation, so that the silicone oil 6 in the first installation cavity 111 receives the pressure from the first diaphragm 4 and transmits the pressure to the first chip 2, so that the first chip 2 can detect the atmospheric pressure or the medium pressure;

[0066] Similarly, the second mounting cavity 121 is connected to the atmosphere through the second oil injection channel 122; its purpose is to inject silicone oil 6 into the second mounting cavity 121 through the second oil injection channel 122 after the second diaphragm 5 covers the second mounting cavity 121; after the silicone oil 6 is injected into the second mounting cavity 121, when the second diaphragm 5 receives the atmospheric pressure or the medium pressure, the second diaphragm 5 produces a deformation along the direction from the second diaphragm 5 to the first mounting cavity 111, and the second diaphragm 5 squeezes the silicone oil 6 in the second mounting cavity 121 through the deformation, so that the silicone oil 6 in the second mounting cavity 121 receives the pressure from the second diaphragm 5 and transmits the pressure to the second chip 3, so that the second chip 3 can detect the atmospheric pressure or the medium pressure.

[0067] After injecting the silicone oil 6, in order to prevent water vapor in the atmosphere from flowing into the first installation cavity 111 or the second installation cavity 121 through the first oil injection channel 112 and the second oil injection channel 122, and in order to prevent the silicone oil 6 from flowing to the outside of the first installation cavity 111 through the first oil injection channel 112, or in order to prevent the silicone oil 6 from flowing to the outside of the second installation cavity 121 through the second oil injection channel 122, it is necessary to seal the first oil injection hole formed by the first oil injection channel 112 and the shell 1, and it is necessary to seal the second oil injection hole formed by the second oil injection channel 122 and the shell 1.

[0068] In this embodiment, see Figure 6 , the first oil injection hole and the second oil injection hole are respectively blocked by a sealing ball 7;

[0069] Specifically, a sealing ball 7 is arranged at the position of the first oil filling hole, so that the sealing ball 7 contacts the contour of the first oil filling hole. At this time, there is still a first gap between the sealing ball 7 and the contour of the first oil filling hole that cannot be directly observed or can be observed by human sight. By welding the sealing ball 7 to the housing 1, the welding position covers the first gap, so that the first sealing structure formed after welding covers the first gap, so that the first gap is sealed by the first sealing structure.

[0070] Similarly, a sealing ball 7 is arranged at the position of the second oil filling hole, so that the sealing ball 7 contacts the contour of the second oil filling hole. At this time, there is still a second gap between the sealing ball 7 and the contour of the second oil filling hole that cannot be directly observed or observed by human sight. By welding the sealing ball 7 to the shell 1, the welding position covers the second gap, and the second sealing structure formed after welding covers the second gap, so that the second gap is sealed by the second sealing structure.

[0071] By adopting the above-mentioned welding method, the first gap between the first sealing ball 7 and the first oil filling hole on the shell 1 (specifically the first section 11) is sealed by the first sealing structure after welding, thereby preventing water vapor from entering the first installation cavity 111 through the first oil filling channel 112; similarly, the second gap between the second sealing ball 7 and the second oil filling hole on the shell 1 (specifically the second section 12) is sealed by the second sealing structure after welding, thereby preventing water vapor from entering the second installation cavity 121 through the second oil filling channel 122.

[0072] For further information, see Figures 4 to 6 , the gauge pressure core of this embodiment, the end faces of the first section 11 at both ends of the axial direction are the first end face 113 and the second end face 114 respectively, and the second section 12 is located at the second end face 114;

[0073] The first oil filling hole is located at the second end surface 114;

[0074] The second oil filling hole is located on the circumferential surface of the second section 12 .

[0075] The gauge pressure core in this embodiment needs to inject silicone oil 6 into the first installation cavity 111 through the first oil injection channel 112 after the first diaphragm 4 is welded to the housing 1 and the second diaphragm 5 is welded to the housing 1, and needs to inject silicone oil 6 into the second installation cavity 121 through the second oil injection channel 122;

[0076] Sealing balls 7 are respectively provided at the first oil filling hole and the second oil filling hole. If the sealing ball 7 is provided at a position protruding from the determined maximum contour of the shell 1, the contour of the sealing ball 7 will increase the maximum contour of the shell 1, which may cause difficulty in installing the gauge pressure core and the mounting cavity of the gauge pressure sensor. Therefore, in order to reduce this installation difficulty, the position of the sealing ball 7 must be set within the range of the maximum contour determined by the shell 1, and the position of the sealing ball 7 is actually the position of the first oil filling hole and the second oil filling hole. Therefore, how to select the positions of the first oil filling hole and the second oil filling hole becomes a technical problem to be solved.

[0077] In this embodiment, the diameter of the first section 11 is greater than the diameter of the second section 12, so that the first section 11 and the second section 12 form a step-like structure, wherein the space between the second end surface 114 and the circumferential surface of the second section 12 forms a processing space;

[0078] When the sealing ball 7 is arranged in the first oil filling hole on the second end surface 114, the sealing ball 7 is actually arranged in the processing space, wherein the sealing ball 7 is actually confined between the first section 11 and the second section 12, and between the circumferential surface of the first section 11 and the circumferential surface of the second section 12, so that the sealing ball 7 is actually confined within the range of the maximum contour determined by the housing 1;

[0079] Similarly, when the sealing ball 7 is arranged on the second oil filling hole located on the circumferential surface of the second section 12, the sealing ball 7 is actually arranged in the processing space, wherein the sealing ball 7 is actually restricted to the side of the second section 12 and to between the circumferential surface of the first section 11 and the circumferential surface of the second section 12, so that the sealing ball 7 is actually restricted within the range of the maximum contour determined by the shell 1.

[0080] The above-mentioned method can avoid the phenomenon that the sealing ball 7 protrudes beyond the maximum contour determined by the housing 1; therefore, the above-mentioned technical solution solves the technical problem of how to select the positions of the first oil filling hole and the second oil filling hole.

[0081] See also Figure 6 , the second end face 114 of the first section 11 is away from the first diaphragm 4 located on the first end face 113; from the perspective of the first oil injection channel 112, the first oil injection channel 112 can be processed along the direction from the second end face 114 to the first end face 113, and the first oil injection channel 112 can reach the first mounting cavity 111, so that the first oil injection channel 112 no longer continues to extend toward the position of the first diaphragm 4; the first oil injection hole is located on the second end face 114, so that the first oil injection hole is actually located in the aforementioned processing space, and when the first oil injection hole is provided with a sealing ball 7, the sealing ball 7 is actually located in the processing space, thereby providing a welding basis for facilitating the welding of the sealing ball 7 and the first oil injection hole to form a first sealing structure.

[0082] See also Figure 6, the circumferential surface of the second section 12 and the end surface of the second section 12 (the end surface covered by the second diaphragm 5) intersect with each other; from the perspective of the second oil injection channel 122, the second oil injection channel 122 can be processed along the radial direction of the second section 12, and the second oil injection channel 122 can reach the second mounting cavity 121, so that the second oil injection channel 122 cannot extend to the position of the first diaphragm 4; the second oil injection hole is located on the circumferential surface of the second section 12, so that the second oil injection hole is actually located in the aforementioned processing space, and when the second oil injection hole is provided with a sealing ball 7, the sealing ball 7 is actually located in the processing space, thereby providing a welding basis for facilitating the welding of the sealing ball 7 and the second oil injection hole to form a second sealing structure.

[0083] During the actual oil injection of the above technical scheme, the intermediate product consisting of the shell 1, the first diaphragm 4 and the second diaphragm 5 is first positioned by a special tooling so that the first diaphragm 4 is located at the lower part of the second diaphragm 5, and the opening direction of the first oil injection hole is positioned vertically upward, and then the silicone oil 6 is injected into the first oil injection channel 112 by a vacuum oil injection machine; the oil outlet direction of the vacuum oil injection machine is vertically downward; after the silicone oil 6 is injected, a sealing ball 7 is set in the first oil injection hole, and the sealing ball 7 and the first section 11 are welded to prevent the silicone oil 6 from flowing from the first installation cavity 111 to the outside of the shell 1; thereafter, the intermediate product is re-positioned by a special tooling so that the opening direction of the second oil injection hole is positioned vertically upward, and then the silicone oil 6 is injected into the second oil injection channel 122 by a vacuum oil injection machine; after the silicone oil 6 is injected, a sealing ball 7 is set in the first oil injection hole, and the sealing ball 7 and the second section 12 are welded to prevent the silicone oil 6 from flowing from the second installation cavity 121 to the outside of the shell 1.

[0084] For further information, see Figures 3 to 6 , Figure 8 The gauge pressure core of this embodiment further includes a first chip base 8 and a second chip base 9;

[0085] The first chip base 8 is disposed in the first mounting cavity 111, and the second chip base 9 is disposed in the second mounting cavity 121. The first chip base 8 and the second chip base 9 are respectively made of ceramic materials;

[0086] The first oil injection channel 112 passes through the first chip base 8 , and the second oil injection channel 122 passes through the second chip base 9 ;

[0087] The first chip 2 is bonded to the first chip base 8 , and the second chip 3 is bonded to the second chip base 9 .

[0088] It has been mentioned in the aforementioned content that the shell 1 is made of metal material; the thermal expansion coefficient of the shell 1 is greater than the thermal expansion coefficient of the first chip 2 and the second chip 3, resulting in that during the thermal expansion of the shell 1, the first chip 2 and the second chip 3, the deformation of the shell 1 is relatively large, while the deformation of the first chip 2 and the second chip 3 is relatively small, thereby cracking the adhesive between the first chip 2 and the second chip 3 and the shell 1 respectively.

[0089] Therefore, the gauge pressure core in the present embodiment is provided with a first chip base 8 made of ceramic material in the first mounting cavity 111, and the first chip 2 is bonded to the first chip base 8. By utilizing the fact that the thermal expansion coefficient of the first chip base 8 is similar or close to that of the first chip 2, the deformation of the first chip base 8 is similar to that of the first chip 2 during the thermal expansion process of the first chip base 8 and the first chip 2, thereby reducing or avoiding the cracking of the adhesive between the first chip 2 and the first chip base 8; similarly, a second chip base 9 made of ceramic material is provided in the second mounting cavity 121, and the second chip 3 is bonded to the second chip base 9. By utilizing the fact that the thermal expansion coefficient of the second chip base 9 is similar or close to that of the second chip 3, the deformation of the second chip base 9 is similar to that of the second chip 3 during the thermal expansion process of the second chip base 9, thereby reducing or avoiding the cracking of the adhesive between the second chip 3 and the second chip base 9.

[0090] In the prior art, the front side of the pressure chip directly receives the atmospheric pressure through the air holes, and the back side of the pressure chip can receive the expansion force generated by the thermal expansion of the metal shell during the thermal expansion process, thereby causing the force on the front side and the force on the back side of the pressure chip to be unbalanced, resulting in chip breakage.

[0091] The gauge pressure core in this embodiment prevents the atmospheric pressure from directly contacting the second chip 3 because the second chip 3 is surrounded by the second diaphragm 5 and the shell 1, and the thermal expansion coefficient of the second chip 3 is similar to the thermal expansion coefficient of the second chip base 9, so that the front and back forces of the second chip 3 are more uniform, reducing or avoiding the occurrence of chip breakage as in the prior art.

[0092] The first chip base 8 is bonded to the housing 1 , and the second chip base 9 is bonded to the housing 1 ;

[0093] In the first mounting cavity 111, the first chip 2 is located between the first chip base 8 and the silicone oil 6. In other words, the silicone oil 6 needs to be injected between the first diaphragm 4 and the first chip base 8, so that the first oil injection channel 112 needs to penetrate the first chip base 8 along the direction from the second end face 114 to the first end face 113, but cannot penetrate the first chip 2. Therefore, a through hole for circulating the silicone oil 6 is provided on the first chip base 8, and the through hole is a part of the first oil injection channel 112;

[0094] Similarly, in the second mounting cavity 121, the second chip 3 is located between the second chip base 9 and the silicone oil 6. To put it another way, the silicone oil 6 needs to be injected between the second diaphragm 5 and the second chip base 9. Thus, the second oil injection channel 122 needs to pass through the second chip base 9 along the aforementioned second section 12, but cannot pass through the second chip 3. Therefore, a through hole for circulating the silicone oil 6 is provided on the second chip base 9, and the through hole is a part of the second oil injection channel 122.

[0095] For further information, see Figure 4 , Figure 5 , Figures 7 to 9 The gauge pressure core of this embodiment further includes a first Kovar alloy pin 01, a second Kovar alloy pin 02 and a third Kovar alloy pin 03;

[0096] The housing 1 is provided with a first channel 04, a second channel 05 and a third channel 06, wherein the first channel 04 and the second channel 05 are respectively located in the first section 11, and the first channel 04 and the second channel 05 are respectively used to connect the first installation cavity 111 and the atmosphere, and the third channel 06 respectively penetrates the first section 11 and the second section 12, and the third channel 06 connects the first installation cavity 111 and the second installation cavity 121;

[0097] Each of the first channels 04 is used to be provided with a first Kovar alloy pin 01, wherein one end of each of the first Kovar alloy pins 01 is located in the first mounting cavity 111, and the other end of each of the second Kovar alloy pins 02 is located outside the housing 1;

[0098] Each second channel 05 is used to be provided with a second Kovar alloy pin 02, wherein one end of each second Kovar alloy pin 02 is located in the first mounting cavity 111, and the other end of each second Kovar alloy pin 02 is located outside the housing 1;

[0099] Each of the third channels 06 is used to be provided with a third Kovar alloy pin 03, wherein one end of each of the third Kovar alloy pins 03 is located in the first mounting cavity 111, and the other end of each of the third Kovar alloy pins 03 is located in the second mounting cavity 121;

[0100] The first chip 2 is electrically connected to the first Kovar alloy pin 01 through a gold wire bonding process;

[0101] The second chip 3 is electrically connected to the third Kovar pin 03 through a gold wire bonding process, and the third Kovar corner is electrically connected to the second Kovar pin 02 through a gold wire bonding process.

[0102] The specific structure of the Kovar alloy pin is common knowledge known to those skilled in the art and will not be described in detail here.

[0103] Any first channel 04 is used to set a first Kovar alloy pin 01, which extends from the inside of the shell 1 to the outside of the shell 1, specifically along the direction from the first end face 113 to the second end face 114. The first Kovar alloy pin 01 extends from the first installation cavity 111 to the outside of the shell 1. The ends of the three first Kovar alloy pins 01 located outside the shell 1 are used to connect the communication line, so that the first chip 2 can receive electrical energy through the first Kovar alloy pin 01, and output the pressure electrical signal generated by the first chip 2 to the outside through the first Kovar alloy pin 01.

[0104] Similarly, any second channel 05 is used to set a second Kovar alloy pin 02, and any third channel 06 is used to set a third Kovar alloy pin 03, wherein the second Kovar alloy pin 02 extends from the inside of the shell 1 to the outside of the shell 1, specifically along the direction from the first end face 113 to the second end face 114, and the second Kovar alloy pin 02 extends from the first installation cavity 111 to the outside of the shell 1, and the third Kovar alloy pin 03 is used to connect 'the end of the second Kovar alloy pin 02 located in the first installation cavity 111' and 'the second chip 3 located in the second installation cavity 121', so the third Kovar alloy pin 03 actually plays the role of changing the direction of connection between the second chip 3 and the second Kovar alloy pin 02, and the ends of the three second Kovar alloy pins 02 located outside the body are used to connect the communication line, so that the second chip 3 can receive electrical energy through the second Kovar alloy pin 02 and the third Kovar alloy pin 03, and output the pressure electrical signal generated by the second chip 3 to the outside through the third Kovar alloy pin 03 and the second Kovar alloy pin 02.

[0105] It should be understood that the end of the first Kovar pin 01 located outside the shell 1 and the end of the second Kovar pin 02 located outside the shell 1 are respectively located in the aforementioned processing space between the second end face 114 and the circumferential surface of the second section 12, so as to avoid the phenomenon that the ends of the first Kovar pin 01 and the second Kovar pin 02 protrude beyond the maximum contour determined by the shell 1.

[0106] For further information, see Figures 3 to 5, the gauge pressure core of this embodiment, the first chip base 8 is provided with a first through hole 07, a second through hole 08 and a third through hole 09;

[0107] The second chip base 9 is provided with a fourth through hole 010;

[0108] The number of the first through holes 07 is the same as the number of the first channels 04, and any first Kovar alloy pin 01 passes through one of the first through holes 07;

[0109] The number of the second through holes 08 is the same as the number of the second channels 05, and any second Kovar alloy pin 02 passes through one of the second through holes 08;

[0110] The number of the third through holes 09 and the number of the fourth through holes 010 are respectively the same as the number of the third channels 06 , and any third Kovar alloy pin 03 passes through one of the third through holes 09 and one of the fourth through holes 010 .

[0111] In order to prevent the silicone oil 6 in the first mounting cavity 111 from flowing to the outside of the housing 1 through the aforementioned first channel 04, firstly, the first chip base 8 is bonded to the housing 1 by an adhesive, and the adhesive is used to seal the gap between the first chip base 8 and the housing 1. Then, a self-sealing structure is formed by the first Kovar alloy pin 01 and the first chip base 8. The principle is that the thermal expansion of the first Kovar alloy pin 01 is similar to the thermal expansion of the first chip base 8 made of ceramic material, so that the first Kovar alloy pin 01 forms an interference fit with the first through hole 07 penetrated by it, thereby forming a self-sealing structure. The self-sealing structure is used to seal the gap between the first Kovar alloy pin 01 and the first chip base 8. Therefore, the silicone oil 6 and the first channel 04 are blocked by the self-sealing structure formed by the first Kovar alloy pin 01 and the first chip base 8 and the adhesive between the first chip base 8 and the housing 1, so that the silicone oil 6 cannot flow to the outside of the housing 1 through the first channel 04.

[0112] Similarly, in order to prevent the silicone oil 6 in the second mounting cavity 121 from flowing to the outside of the housing 1 through the aforementioned second channel 05, first, the first chip base 8 is bonded to the housing 1 by an adhesive, and the adhesive is used to seal the gap between the first chip base 8 and the housing 1. Then, a self-sealing structure is formed by the second Kovar alloy pin 02 and the first chip base 8. The principle is the same as the principle of the self-sealing structure formed by the first Kovar alloy pin 01 and the first chip base 8. The difference is that the second Kovar alloy pin 02 here penetrates the first through hole. The rest is not repeated here. The self-sealing structure is used to seal the gap between the second Kovar alloy pin 02 and the first chip base 8. Therefore, the silicone oil 6 and the second channel 05 are blocked by the self-sealing structure formed by the second Kovar alloy pin 02 and the first chip base 8 and the adhesive between the first chip base 8 and the housing 1, so that the silicone oil 6 cannot flow to the outside of the housing 1 through the second channel 05.

[0113] Furthermore, in order to prevent the silicone oil 6 in the first installation cavity 111 from flowing into the second installation cavity 121 through the aforementioned third channel 06, firstly, in the first installation cavity 111, the first chip base 8 and the housing 1 are bonded by adhesive, and the adhesive is used to seal the gap between the first chip base 8 and the housing 1, and then, a self-sealing mechanism is formed by the third Kovar alloy pin 03 and the first chip base 8, and its principle is the same as the principle of the self-sealing structure formed by the first Kovar alloy pin 01 and the first chip base 8, except that the third Kovar alloy pin 03 here penetrates the third through hole 09, and the rest is not repeated here, and the self-sealing structure is used to seal the gap between the third Kovar alloy pin and the first chip base 8, so that the silicone oil 6 in the first installation cavity 111 and the third channel 06 are blocked by the self-sealing mechanism formed by the third Kovar alloy pin 03 and the first chip base 8 and the adhesive between the first chip base 8 and the housing 1, so that the silicone oil 6 in the first installation cavity 111 cannot flow into the second installation cavity 121 through the third channel 06;

[0114] In addition, in order to prevent the silicone oil 6 in the second mounting cavity 121 from flowing into the first mounting cavity 111 through the aforementioned third channel 06, first, in the second mounting cavity 121, the second chip base 9 is bonded to the housing 1 by adhesive, and the adhesive is used to seal the gap between the second chip base 9 and the housing 1. Then, a self-sealing mechanism is formed by the third Kovar alloy pin 03 and the second chip base 9. The principle is the same as the principle of the self-sealing structure formed by the first Kovar alloy pin 01 and the first chip base 8. The difference is that the Kovar alloy pin here penetrates the fourth through hole 010. The rest is not repeated here. The self-sealing structure is used to seal the gap between the third Kovar alloy pin and the second chip base 9. Therefore, the silicone oil 6 and the third channel 06 in the second mounting cavity 121 are blocked by the self-sealing mechanism formed by the third Kovar alloy pin 03 and the second chip base 9 and the adhesive between the second chip base 9 and the housing 1, so that the silicone oil 6 in the second mounting cavity 121 cannot flow into the first mounting cavity 111 through the third channel 06.

[0115] It should be understood that if the silicone oil 6 in the first installation cavity 111 can flow to the outside of the shell 1 through the first channel 04 and / or the second channel 05, and if the silicone oil 6 in the first installation cavity 111 can flow to the second installation cavity 121 through the third channel 06, then the pressure applied by the first diaphragm 4 to the first chip 2 through the silicone oil 6 will produce a pressure difference with the atmospheric pressure received by the first diaphragm 4, resulting in inaccurate measurement of the first chip 2; similarly, if the silicone oil 6 in the second installation cavity 121 can flow to the first installation cavity 111 through the third channel 06, then the pressure applied by the second diaphragm 5 to the second chip 3 through the silicone oil 6 will produce a pressure difference with the atmospheric pressure received by the second diaphragm 5, resulting in inaccurate measurement of the second chip 3.

[0116] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. Gauge pressure core, characterized in that: It includes a housing, a first chip, a second chip, a first diaphragm, a second diaphragm and silicone oil; The shell is made of metal material, and is configured into a first section and a second section, the first section and the second section are respectively configured as a cylinder, the diameter of the first section is greater than the diameter of the second section, and the first section and the second section are coaxial and integrally manufactured; Along the direction from the first section to the second section, the first section is recessed to form a first mounting cavity, and along the direction from the second section to the first section, the second section is recessed to form a second mounting cavity, the first chip is disposed in the first mounting cavity, and the second chip is disposed in the second mounting cavity; The first diaphragm covers the first installation cavity, the second diaphragm covers the second installation cavity, and the first installation cavity and the second installation cavity are configured to be isolated from each other.

2. The gauge pressure core according to claim 1, characterized in that: It also includes a first oil injection channel and a second oil injection channel, wherein the first oil injection channel is used to connect the first mounting cavity and the atmosphere, and the second oil injection channel is used to connect the second mounting cavity and the atmosphere, and the silicone oil is configured to be injected into the first mounting cavity through the first oil injection channel, and the silicone oil is configured to be injected into the second mounting cavity through the second oil injection channel. It also includes a sealing ball, which is made of metal material; The first oil injection channel and the surface of the first section form a first oil injection hole, and the first oil injection hole is covered by the first sealing ball, wherein the gap between the first sealing ball and the first section is defined as a first gap, and the first gap forms a first sealing structure by welding the first sealing ball and the first section; The second oil injection channel and the surface of the first section form a second oil injection hole, and the second oil injection hole is covered by the second sealing ball, wherein the gap between the second sealing ball and the first section is defined as a second gap, and the second gap forms a second sealing structure by welding the second sealing ball to the first section.

3. The gauge pressure core according to claim 2, characterized in that: The end faces of the first section at both axial ends are respectively a first end face and a second end face, and the second section is located at the second end face; The first oil filling hole is located on the second end surface; The second oil filling hole is located on the circumferential surface of the second section.

4. The gauge pressure core according to any one of claims 1 to 3, characterized in that: Also included is a first chip base and a second chip base; The first chip base is arranged in the first mounting cavity, the second chip base is arranged in the second mounting cavity, and the first chip base and the second chip base are respectively made of ceramic materials; The first oil injection channel passes through the first chip base, and the second oil injection channel passes through the second chip base; The first chip is bonded to the first chip base, and the second chip is bonded to the second chip base.

5. The gauge pressure core according to claim 4, characterized in that: Also included is a first kovar pin, a second kovar pin, and a third kovar pin; The housing is provided with a first channel, a second channel and a third channel, wherein the first channel and the second channel are respectively located in the first section, the first channel and the second channel are respectively used to connect the first installation cavity and the atmosphere, the third channel passes through the first section and the second section, and the third channel connects the first installation cavity and the second installation cavity respectively; Each of the first channels is respectively used to be provided with a first Kovar alloy pin, wherein one end of each of the first Kovar alloy pins is located in the first mounting cavity, and the other end of each of the first Kovar alloy pins is located outside the housing; Any of the second channels is respectively used to be provided with a second Kovar alloy pin, wherein one end of any of the second Kovar alloy pins is located in the first mounting cavity, and the other end of any of the second Kovar alloy pins is located outside the housing; Each of the third channels is used to be provided with a third Kovar alloy pin, wherein one end of each of the third Kovar alloy pins is located in the first mounting cavity, and the other end of each of the third Kovar alloy pins is located in the second mounting cavity; The first chip is electrically connected to the first Kovar alloy pin through a gold wire bonding process; The second chip is electrically connected to the third Kovar pin through a gold wire bonding process, and the third Kovar corner is electrically connected to the second Kovar pin through a gold wire bonding process.

6. The gauge pressure core according to claim 5, characterized in that: The first chip base is provided with a first through hole, a second through hole and a third through hole; The second chip base is provided with a fourth through hole; The number of the first through holes is the same as the number of the first channels, and any one of the first Kovar alloy pins passes through one of the first through holes; The number of the second through holes is the same as the number of the second channels, and any one of the second Kovar alloy pins passes through one of the second through holes; The number of the third through holes and the number of the fourth through holes are respectively the same as the number of the third channels, and any one of the third Kovar alloy pins passes through one of the third through holes and one of the fourth through holes respectively.

7. The gauge pressure core according to claim 1, characterized in that: Also includes a first pressure ring and a second pressure ring; The first pressing ring and the second pressing ring are respectively made of metal materials; The first diaphragm is arranged between the first pressure ring and the first section, and the first pressure ring, the first diaphragm and the first section are welded together; The second diaphragm is arranged between the second pressure ring and the second section, and the second pressure ring, the second diaphragm and the second section are welded into one.

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