Method for arranging electrode leads of measuring pump of nitrogen-oxygen sensor

Abstract

According to the arrangement method for the electrode leads of the measuring pump of the nitrogen-oxygen sensor, the electrode leads of the measuring pump are laid to extend along a path to avoid an expansion area of a measuring pump chamber, so that irregular gaps S surrounding the electrode leads of the main pump, the electrode leads of the auxiliary pump and the electrode leads of the measuring pump are not generated in the expansion area of the measuring pump chamber. The improved measurement pump electrode lead laying path avoids the measurement pump chamber expansion area, so that irregular gaps generated around the measurement pump electrode lead are not communicated with the measurement pump chamber, and negative effects on measurement results and precision are avoided.

Description

[0001] This application is a divisional application of application number 2022109921800. The filing date of the original application is August 18, 2022. The name of the invention is "A method for arranging electrode leads of a nitrogen oxide sensor." Technical Field

[0002] The invention relates to the field of nitrogen oxygen sensor manufacturing, and in particular to a method for arranging internal electrode leads of a nitrogen oxygen sensor. Background Art

[0003] Nitrogen oxide sensors are mainly used to detect the concentration of specific gases such as NOx in vehicle exhaust. Their working principle is to decompose NOx in exhaust gas into nitrogen and oxygen on electrodes, and detect NOx concentration based on the current generated by the flow of oxygen obtained by decomposition between electrodes. The structure of a general nitrogen oxide sensor is as follows: Figure 1 As shown, there are an outer electrode layer 1, an inner electrode layer 2, a chamber layer 3, a measuring electrode layer 4, a reference electrode layer 5 and a heater layer 6 stacked in sequence from top to bottom (it can be seen from the figure that there are actually two layers stacked). Figure 1 The main positional relationship between the stacked structures is shown. In fact, there are also auxiliary stacked structures such as insulating layers and sacrificial layers between the layers, which are omitted and not shown because they have no direct relationship with the present invention. In the chamber layer 3, there are tail gas chamber buffer chamber 31, main pump chamber 32, auxiliary pump chamber 33, and measuring pump chamber 34 connected from left (gas inlet) to right. The chamber layer 3 is formed by stamping to form the aforementioned chambers, and the upper and lower end surfaces of each chamber are closed by stacking the upper inner electrode layer 2 and the lower measuring electrode layer 4. The main pump electrode 21 and the auxiliary pump electrode 22 are attached to the lower surface of the inner electrode layer 2. The main pump electrode 21 and the auxiliary pump electrode 22 are respectively connected to the main pump electrode pin 11 and the auxiliary pump electrode pin 12 in the chip pin on the upper surface of the outer electrode layer 1 after being led out through the main pump electrode lead 23 and the auxiliary pump electrode lead 24. A measurement pump electrode 41 (measurement electrode) is attached to the measurement electrode layer 4 and is connected to a measurement pump electrode pin 13 among chip pins on the upper surface of the outer electrode layer 1 via a measurement pump electrode lead 42 .

[0004] Figure 2a The stacked inner electrode layer 2, the chamber layer 3, and the measuring electrode layer 4 are shown. Figure 2b The internal main pump chamber 32, auxiliary pump chamber 33, measuring pump chamber 34 and the related electrode lead lines are shown. Figure 2b and Figure 2a It can be seen that the measuring pump chamber 34 is a three-dimensional area surrounded by thick solid lines. By expanding the measuring pump chamber 34 toward the side of the chamber layer 3, a measuring pump chamber expansion area 35 surrounded by thin dotted lines can be formed. Figure 2c for Figure 2bA-direction sectional view, from which it can be seen that the measuring pump electrode lead 42 enters the measuring pump chamber 34 from the measuring pump chamber expansion area 35, and the main pump electrode lead 23 and the auxiliary pump electrode lead 24 pass through the measuring pump chamber expansion area 35 respectively. In the manufacturing process of the nitrogen oxygen sensor, the inner electrode layer 2, the chamber layer 3, and the measuring electrode layer 4 are all made of ZrO2 green embryos, and the measuring pump electrode lead 42, the main pump electrode lead 23, and the auxiliary pump electrode lead 24 are all superimposed therein. Since the toughness of the ZrO2 green embryo is poor, the electrode lead has a certain thickness. If it is superimposed between adjacent ZrO2 green embryos, the composite ceramic sheet will have a certain bending deformation due to the thickness of the electrode lead. This deformation cannot fit around the electrode lead, so that an irregular gap S is formed around the electrode lead (such as Figure 2c As shown); if the electrode lead attachment groove is reserved, irregular gaps S may be generated due to the offset of machining superposition or the size error between the groove and the electrode lead. The influence of the irregular gaps S around the measuring pump electrode lead 42, the main pump electrode lead 23, and the auxiliary pump electrode lead 24 is also different: especially for the irregular gaps S generated by the measuring pump electrode lead 42, because it is generated around the measuring pump chamber 34, and because the measuring pump electrode lead 42 enters the measuring pump chamber 34, the irregular gaps S are connected to the measuring pump chamber 34, which will cause the NOx and other specific gases in the measuring pump chamber 34 to enter the irregular gaps S. Even worse, if the irregular gaps S are connected to the outside (the distance between the measuring pump electrode lead 42 and the edge of the measuring electrode layer 4 is very small, this possibility is very high), the external gas will be directly introduced into the measuring pump chamber 34. In any case, the NOx and other specific gas components in the measuring pump chamber 34 will change, which will ultimately greatly affect the measurement results and accuracy. As for the irregular gaps S around the main pump electrode leads 23 and the auxiliary pump electrode leads 24, on the one hand, they are similar to the irregular gaps S generated by the aforementioned measuring pump electrode leads 42, which will cause irregular gaps S to be generated around the main pump electrode leads 23 and the auxiliary pump electrode leads 24 entering the main pump chamber 32 and the auxiliary pump chamber 33, changing the NOx and other specific gas components in the chamber. However, since the main pump chamber 32 and the auxiliary pump chamber 33 have the function of feedback regulating NOx and other specific gas components during operation, the impact of the irregular gaps S is much smaller than that of the measuring pump chamber 34. On the other hand, according to Figure 2c It can be seen that since the main pump electrode lead 23 and the auxiliary pump electrode lead 24 pass through the measuring pump chamber extension area 35, the distance between the measuring pump chamber extension area 35 and the edge of the measuring electrode layer 4 is very small. The irregular gap S is very likely to be connected to the measuring pump chamber 34, and may be connected to the external space at the same time. In any case, as long as it is connected to the measuring pump chamber 34, the gas in the irregular gap S will also change the specific gas components such as NOx, which will ultimately affect the measurement results and accuracy.

[0005] Through patent search, it was found in the Chinese patent document with publication number CN110741249A that an attempt was made to use an insulating layer wrapping the leading end of the electrode lead to improve the impact of the above-mentioned irregular gaps. However, even if the leading end of the electrode lead is wrapped with an insulating layer, irregular gaps S will still be generated on the periphery of the leading end insulating layer, and the above-mentioned technical problems cannot be effectively improved.

[0006] It can be seen from this that the arrangement of each electrode lead needs to be optimized and improved to avoid the irregular gap S generated around the electrode lead affecting the measurement results and accuracy. Summary of the invention

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a method for arranging electrode leads of a nitrogen oxygen sensor measuring pump, wherein the nitrogen oxygen sensor comprises a chamber layer, wherein a measuring pump chamber is provided in the chamber layer, wherein the measuring pump chamber is formed by enclosing an upper layer and a lower layer of the chamber layer, wherein the measuring pump chamber is extended toward the side of the chamber layer to form an extended region of the measuring pump chamber, and an extended path of laying the electrode leads of the measuring pump is avoided in the extended region of the measuring pump chamber; The measuring pump electrode lead is laid in an extended path to avoid the measuring pump chamber expansion area by setting a measuring pump electrode via in the measuring electrode layer, so that one end of the measuring pump electrode via is vertically connected to the bottom of the measuring pump electrode, and the other end is vertically connected to the measuring pump electrode lead, and the measuring pump electrode lead is laid in a layer that is not the same as the measuring pump chamber expansion area.

[0008] Furthermore, the measuring electrode layer is divided into two layers, the measuring pump electrode vias extend vertically downward between the two layers, the measuring pump electrode leads are laid between the two layers and led out from the rear side elevation of the measuring electrode layer through the rear side elevation of the measuring electrode layer to be connected with the measuring pump electrode pins.

[0009] Furthermore, the measuring electrode layer is divided into an upper and lower layer, the measuring pump electrode vias extend vertically downward between the upper and lower layers, the measuring pump electrode leads are laid between the upper and lower layers and penetrate the measuring electrode layer, the chamber layer, the inner electrode layer, and the outer electrode layer, and are connected to the measuring pump electrode pins through the measuring pump electrode lead vias.

[0010] The present invention has the following advantages: the improved measurement pump electrode lead laying path avoids the measurement pump chamber expansion area, so that the irregular gaps generated around the measurement pump electrode lead will not be connected to the measurement pump chamber, avoiding negative impact on measurement results and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 : Schematic diagram of the layered structure of the prior art nitrogen oxide sensor; Figure 2a : Schematic diagram of the electrode lead laying path of the prior art nitrogen oxygen sensor Figure 1 ; Figure 2b : Schematic diagram 2 of the electrode lead laying path of the prior art nitrogen oxide sensor; Figure 2c : Figure 2b A-direction sectional view; Figure 3 : Schematic diagram of electrode lead laying path in embodiment 1; Figure 4 : Figure 3 A-direction sectional view; Figure 5 : Schematic diagram of electrode lead laying path in embodiment 1; Figure 6 : Schematic diagram of electrode lead laying path in embodiment 2; Figure 7 : Schematic diagram of electrode lead laying path in Example 3; Figure 8 : Schematic diagram of electrode lead laying path in Example 4; Fig. 9 : Schematic diagram of electrode lead laying path in Example 5; Fig.10 : Schematic diagram of electrode lead laying path in Example 6; Fig.11 : Schematic diagram of the laying method of the main pump electrode lead and the auxiliary pump electrode lead in Example 3 and Example 6. DETAILED DESCRIPTION

[0012] In order to enable those skilled in the art to fully implement the present invention, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. The directional expressions of front, back, left, and right in the drawings of this specification correspond to the directional markings in the drawings.

[0013] Embodiment 1: Figure 3-Figure 5 As shown, a method is provided to use vias to lead the measurement pump electrode lead 42 out in a staggered layer to avoid the measurement pump chamber expansion area 35.

[0014] In the measuring electrode layer 4, a measuring pump electrode via 71 is vertically connected to the bottom of the measuring pump electrode 41. The measuring pump electrode via 71 should be led out vertically downward to the central position of the measuring electrode layer 4, and a measuring pump electrode lead 42 is connected to the end of the measuring pump electrode via 71 away from the measuring pump electrode 41. The measuring pump electrode lead 42 extends in the middle of the measuring electrode layer 4 and is finally led out at the rear elevation of the measuring electrode layer 4. The measuring electrode layer 4 is a single-layer structure in the prior art. In this embodiment, in order to achieve the laying of the measuring pump electrode lead 42 in the center of the layer, the measuring electrode layer 4 can be divided into an upper and lower layer (4a, 4b). During processing and manufacturing, the measuring pump electrode lead 42 is laid in the middle of the upper and lower layers (4a, 4b) of the measuring electrode layer 4. In order to keep the overall thickness of the sensor consistent, the sum of the thickness of the upper and lower layers (4a, 4b) is the thickness of the measuring electrode layer 4. Figure 5 It can be seen that one end of the measurement pump electrode via 71 is vertically connected to the measurement pump electrode 41, and the other end is connected to the measurement pump electrode lead 42, thereby avoiding the measurement pump electrode lead 42 and the measurement pump chamber expansion area 35. Since the connection between the measurement pump electrode 41 and the measurement pump electrode via 71 can ensure sealing, even if an irregular gap S is generated during the laying process of the measurement pump electrode lead 42 after the staggered layer, since the irregular gap S is avoided due to the staggered laying of the measurement pump electrode lead 42 and the measurement pump chamber expansion area 35, no irregular gap S is generated within the measurement pump chamber expansion area 35, thereby avoiding the negative impact of the irregular gap S and the measurement pump chamber 34 on the measurement result and accuracy.

[0015] It is a preferred implementation to lay the measuring pump electrode lead 42 between the upper and lower layers (4a, 4b) of the measuring electrode layer 4. Generally, for the purpose of staggering the measuring pump electrode lead 42 to avoid the measuring pump chamber expansion area 35, the measuring pump electrode lead 42 can also be led to the upper surface of the reference electrode layer 5 through the vertically downward via 71. However, since the reference electrode 51 and related leads exist on the upper surface of the reference electrode layer 5, it is necessary to control the spacing between the measuring pump electrode lead 42 and the reference electrode 5 and its leads to avoid interference, which increases the difficulty of manufacturing.

[0016] After the above method is used for the bottom of the measurement pump electrode 41 in the measurement electrode layer 4, the main pump electrode lead 23 and the auxiliary pump electrode lead 24 in the main pump chamber 32 and the auxiliary pump chamber 33 also avoid the measurement pump chamber expansion area 35 by adopting the via staggered layer method. Specifically, the main pump electrode 21 and the auxiliary pump electrode 22 lead the main pump electrode lead 23 and the auxiliary pump electrode lead 24 to the upper surface of the inner electrode layer 2 through the vertically upward main pump electrode via 72 and the auxiliary pump electrode via 73, respectively. The main pump electrode lead 23 and the auxiliary pump electrode lead 24 extend from the upper surface of the inner electrode layer 2 to the front side of the inner electrode layer 2 and are led out. The main pump electrode lead 23 and the auxiliary pump electrode lead 24 in the main pump chamber 32 and the auxiliary pump chamber 33 can also avoid the measurement pump chamber expansion area 35 by adopting the through-hole staggered layer method, and can also avoid the irregular gap S around the main pump electrode lead 23 and the auxiliary pump electrode lead 24 from being connected to the main pump chamber 32 and the auxiliary pump chamber 33, thereby further reducing the negative impact of the irregular gap on the measurement results and accuracy.

[0017] Through the above method, the measurement pump electrode lead 42 is led out from the rear side elevation of the measurement electrode layer 4, and the main pump electrode lead 23 and the auxiliary pump electrode lead 24 are led out from the front side elevation of the inner electrode layer 2. The measurement pump electrode lead 42 and the measurement pump electrode pin 13 are connected on the rear side elevation of the measurement electrode layer 4 through a conductive printed layer. The main pump electrode lead 23, the auxiliary pump electrode lead 24 and the main pump electrode pin 11 and the auxiliary pump electrode pin 12 are connected on the front side elevation of the inner electrode layer 2 through a conductive printed layer. The main pump electrode lead 23, the auxiliary pump electrode lead 24 and the measurement pump electrode lead 42 are not on the same side elevation, and the lead-out section of the measurement pump electrode lead 42 is laid separately on the rear side elevation of the measurement electrode layer 4 to avoid circuit interference.

[0018] Embodiment 2 (such as Figure 3 , Figure 4 , Figure 6 ): The laying method of the measuring pump electrode lead 42 is the same as that in the first embodiment, and the measuring pump electrode lead 42 is led out in a staggered layer by a via hole to avoid the measuring pump chamber expansion area 35. The measuring pump electrode lead 42 extends in the middle of the measuring electrode layer 4 and is finally led out at the rear side elevation of the measuring electrode layer 4.

[0019] The difference from the first embodiment is that the lead-out method of the main pump electrode lead 23 and the auxiliary pump electrode lead 24 is different. The laying method of the main pump electrode lead 23 and the auxiliary pump electrode lead 24 is consistent with that of the embodiment, and the main pump electrode lead 23 and the auxiliary pump electrode lead 24 also avoid the measurement pump chamber expansion area 35 by using the via staggered layer method. Specifically, the main pump electrode 21 and the auxiliary pump electrode 22 lead the main pump electrode lead 23 and the auxiliary pump electrode lead 24 to the upper surface of the inner electrode layer 2 through the vertically upward main pump electrode via 72 and the auxiliary pump electrode via 73 respectively. The main pump electrode lead 23 and the auxiliary pump electrode lead 24 extend to the right on the upper surface of the inner electrode layer 2 to just below the main pump electrode pin 11 and the auxiliary pump electrode pin 12, and the main pump electrode pin 11 and the main pump electrode lead 23 are connected by the main pump electrode lead via 75 that penetrates the outer electrode layer 1; the auxiliary pump electrode lead via 76 connects the auxiliary pump electrode lead 24 and the auxiliary pump electrode pin 12.

[0020] Embodiment 3 (such as Figure 3 , Fig.11 , Figure 7 ): The difference from the second embodiment is that the laying method of the main pump electrode lead 23 and the auxiliary pump electrode lead 24 is different.

[0021] As described in the background technology section of the present application, even if the irregular gaps S generated around the main pump electrode leads 23 and the auxiliary pump electrode leads 24 are connected to the main pump chamber 32 and the auxiliary pump chamber 33, the impact on the overall measurement accuracy of the sensor is much smaller than that of the irregular gaps S being connected to the measuring pump chamber 34. Therefore, the present embodiment only considers that the main pump electrode leads 23 and the auxiliary pump electrode leads 24 are not laid out in layers to avoid the measuring pump chamber expansion area 35, so as to prevent the irregular gaps S around them from being generated in the measuring pump chamber expansion area 35.

[0022] Therefore, a relatively simple method can be used for laying the main pump electrode lead 23 and the auxiliary pump electrode lead 24. The main pump electrode lead 23 and the auxiliary pump electrode lead 24 can still be laid in the adjacent surface of the current inner electrode layer 2 and the chamber layer 3, and not laid in a staggered layer with the measurement pump chamber expansion area 35. Since the laying path needs to avoid the measurement pump chamber expansion area 35, the laying path of the main pump electrode lead 23 and the auxiliary pump electrode lead 24 can be selected in the surface area to the left of the measurement pump chamber expansion area 35 (such as Fig.11 shaded area).

[0023] One way is to extend the main pump electrode lead 23 and the auxiliary pump electrode lead 24 directly from the main pump electrode 21 and the auxiliary pump electrode 22 to the front side elevation of the inner electrode layer 2, respectively, without extending along the left and right direction of the inner electrode layer 2. Obviously, although this laying method is simpler than the via lead-out method of the first embodiment, it can also completely avoid the main pump electrode lead 23 and the auxiliary pump electrode lead 24 from penetrating the measurement pump chamber expansion area 35, so that the irregular gap S around them will not be connected to the measurement pump chamber expansion area 35.

[0024] After the main pump electrode lead 23 and the auxiliary pump electrode lead 24 extend to the front side elevation of the inner electrode layer 2 , they extend vertically upward to the upper surface of the outer electrode layer 1 and extend to the right to finally connect with the main pump electrode pin 11 and the auxiliary pump electrode pin 12 .

[0025] Embodiment 4 (such as Figure 3 , Figure 4 , Figure 8 )、Example 5(such as Figure 3 , Figure 4 , Fig. 9 )、Example 6(such as Figure 3 , Fig.11 , Fig.10 ) The lead-out methods of the measurement pump electrode lead wire 42 in the second embodiment, the first embodiment, and the third embodiment are changed respectively, as follows: The measuring pump electrode lead 42 extends from the middle of the measuring electrode layer 4 to the right to just below the measuring pump electrode pin 13 , and the measuring pump electrode lead via 74 passes through the measuring electrode layer 4 , the chamber layer 3 , the inner electrode layer 2 , and the outer electrode layer 1 and then connects the measuring pump electrode lead 42 and the measuring pump electrode pin 13 .

[0026] Obviously, the above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A method for arranging electrode leads of a nitrogen oxygen sensor measuring pump, the nitrogen oxygen sensor comprising a chamber layer (3), wherein the chamber layer (3) has a measuring pump chamber (34), the measuring pump chamber (34) being formed by laminating and sealing an upper layer and a lower layer of the chamber layer (3), characterized in that: The measuring pump chamber (34) is extended toward the side of the chamber layer (3) to form a measuring pump chamber extension area (35), and the measuring pump electrode lead (42) is laid out along an extension path to avoid the measuring pump chamber extension area (35); The measuring pump electrode lead (42) is laid out in an extended path to avoid the measuring pump chamber expansion area (35) by providing a measuring pump electrode via (71) in the measuring electrode layer (4), with one end of the measuring pump electrode via (71) vertically connected to the bottom of the measuring pump electrode (41) and the other end of the measuring pump electrode via (71) vertically connected to the measuring pump electrode lead (42), so that the measuring pump electrode lead (42) is led out in a staggered manner to avoid the measuring pump chamber expansion area (35).

2. The method for arranging electrode leads of a nitrogen oxygen sensor measuring pump as claimed in claim 1, characterized in that: The measuring electrode layer (4) is divided into an upper and lower layer (4a, 4b), the measuring pump electrode via (71) vertically extends downward to between the upper and lower layers (4a, 4b), the measuring pump electrode lead (42) is laid between the upper and lower layers (4a, 4b) and is led out from the rear side elevation of the measuring electrode layer (4) and connected to the measuring pump electrode pin (13) through the rear side elevation of the measuring electrode layer (4).

3. The method for arranging electrode leads of a nitrogen oxygen sensor measuring pump according to claim 1, characterized in that: The measuring electrode layer (4) is divided into an upper and lower layer (4a, 4b); a measuring pump electrode via (71) vertically extends downward to between the upper and lower layers (4a, 4b); a measuring pump electrode lead (42) is laid between the upper and lower layers (4a, 4b) and penetrates through the measuring electrode layer (4), the chamber layer (3), the inner electrode layer (2), and the measuring pump electrode lead via (74) of the outer electrode layer (1) to be connected to the measuring pump electrode pin (13).

Images