Lead-free oxygen sensor and shell thereof

Abstract

The utility model relates to a lead-free oxygen sensor and a shell thereof. The sensor comprises a shell, an electrochemical reaction layer is arranged in the shell, the electrochemical reaction layer comprises a working electrode, a reference electrode and a counter electrode, the shell comprises an upper cover and a shell, an air inlet is formed in the upper cover, an electrolyte cavity is formed in the shell, and a liquid injection port and an air outlet are formed in the shell. A protrusion is arranged on the outer side wall of the shell, a first groove is formed in the protrusion, and a pin mounting hole is formed in the groove bottom of the first groove. The contact pins are connected with the corresponding electrodes through metal conductive wires, through holes are formed in the shell, and the metal conductive wires penetrate through the through holes to seal and block the through holes. The first groove is provided with a gland, and the gland is used for blocking and protecting the metal conductive wire and the pin. According to the utility model, the upper cover and the shell of the sensor are in ultrasonic connection without influencing the metal conductive wire and the contact pin, so that the problems of contact pin liquid leakage and metal conductive wire damage caused by ultrasonic connection of the upper cover and the shell in the prior art can be solved.

Description

Technical Field

[0001] The utility model relates to the field of oxygen sensors, in particular to a lead-free oxygen sensor and a shell thereof. Background Art

[0002] Among the numerous electrochemical gas sensors, oxygen sensors are used in significant quantities and have the widest range of applications. The demand for oxygen sensors across various industries approaches the combined total for all other gas sensors. Traditional lead-based oxygen sensors, however, suffer from sensor degradation due to the generation of PbO as the lead block is consumed. The expansion of the lead block releases internal stress within the sensor, leading to severe electrolyte leakage. Corrosion of the sensor housing and pins can also contaminate and damage the instrument's PCB, severely impacting sensor performance, shortening its lifespan, causing sensor failure and permanent damage, and even leading to environmental pollution and personal safety concerns. For example, patent application publication number CN101339157 B directly passes a metal conductive wire through the lead block. This can easily damage the metal during assembly, leading to assembly failure and significant waste of housing materials, labor, and resources. Furthermore, the high concentration of oxygen in the air causes the lead-based oxygen sensor to be constantly exposed to the air, causing oxygen to continuously react with the catalyst, resulting in a consumption-type sensor. This accelerates lifespan degradation and significantly shortens the lifespan of the lead-based oxygen sensor.

[0003] Therefore, the industry has developed a long-life, lead-free oxygen sensor to overcome the problems caused by lead. However, while lead-free oxygen sensors are pollution-free and have a long lifespan, they still suffer from pin leakage and metal filament damage. Furthermore, with the continuous advancement of technology, oxygen sensors are moving towards miniaturization, integration, modularization, and intelligence to meet the needs of small devices and intelligent systems. However, miniaturization also means that the sensor's size is also shrinking, leading to conflicting design requirements within the sensor. For example, most current lead-free oxygen sensors mainly consist of a housing, a waterproof and breathable membrane, a working electrode, a reference electrode, a counter electrode, an electrolyte, a metal filament, and pins. Each pin is welded with a metal filament for electrical connection to the corresponding electrode, and the housing is equipped with an air inlet, an electrolyte injection port, and an air outlet. However, when the upper cover of existing lead-free oxygen sensors is ultrasonically connected to the housing, especially when the ultrasonic energy is too high, the pins and the metal filaments can loosen, causing damage to the metal filaments and electrolyte leakage from the pins, resulting in sensor failure. Therefore, there is a need to design a small-sized, lead-free oxygen sensor that can address sensor pin leakage and metal filament damage. Utility Model Content

[0004] The purpose of the utility model is to provide a lead-free oxygen sensor housing to solve the technical problems of liquid leakage and damage to the metal conductive wire when the upper cover and the housing are ultrasonically connected in the prior art; at the same time, the purpose of the utility model is also to provide a lead-free oxygen sensor using the above housing.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical solution for a lead-free oxygen sensor housing: a lead-free oxygen sensor housing, comprising an upper cover and a shell, the upper cover is provided with an air inlet, an electrolyte chamber is provided in the shell, the shell is provided with a liquid injection port connected to the electrolyte chamber, and the shell is also provided with an air outlet, a protrusion is provided on the outer wall of the shell, a first groove is provided on the protrusion, a pin mounting hole is provided on the bottom of the first groove, a through hole is provided on the shell for a metal conductive wire for connecting to the pin to pass through, the first groove is equipped with a pressure cover, and the pressure cover is used to seal and protect the metal conductive wire and the pin.

[0006] A channel for a metal conductive wire connected to the pin to pass through is provided between the pressure cover and the outer side wall of the shell.

[0007] A second groove is provided on the outer side wall of the shell, a through hole is provided on the bottom of the second groove, and a gap is provided between the side of the pressure cover facing the shell and the outer side wall of the shell to form the above-mentioned channel.

[0008] The pressure cover includes a first pressure cover portion for blocking the first groove and the second groove, and also includes a second pressure cover portion extending into the first groove for pressing and fixing the pin connected to the metal conductive wire.

[0009] The first portion of the pressure cover and the second portion of the pressure cover form a longitudinal cross-section of an inverted "convex"-shaped structure with a larger upper portion and a smaller lower portion.

[0010] The utility model adopts the following technical solution: a lead-free oxygen sensor, comprising a shell, an electrochemical reaction layer is arranged inside the shell, the electrochemical reaction layer includes a working electrode, a reference electrode and a counter electrode, the shell includes an upper cover and a shell body, the upper cover is provided with an air inlet, an electrolyte cavity is provided in the shell body, the shell body is provided with a liquid injection port connected to the electrolyte cavity, and the shell body is also provided with an air outlet, a protrusion is provided on the outer wall of the shell body, a first groove is provided on the protrusion, a pin mounting hole is provided on the bottom of the first groove for mounting a pin; the pin is connected to the corresponding electrode through a metal conductive wire, a through hole is provided on the shell body for the metal conductive wire to pass through, and after the metal conductive wire passes through the through hole, the through hole is sealed and blocked to prevent the electrolyte from passing through; the first groove is equipped with a pressure cover, and the pressure cover is used to seal and protect the metal conductive wire and the pin.

[0011] A channel for a metal conductive wire connected to the pin to pass through is provided between the pressure cover and the outer side wall of the shell.

[0012] A second groove is provided on the outer side wall of the shell, a through hole is provided on the bottom of the second groove, and a gap is provided between the side of the pressure cover facing the shell and the outer side wall of the shell to form the above-mentioned channel.

[0013] The pressure cover includes a first pressure cover portion for blocking the first groove and the second groove, and also includes a second pressure cover portion extending into the first groove for pressing and fixing the pin connected to the metal conductive wire.

[0014] The first portion of the pressure cover and the second portion of the pressure cover form a longitudinal cross-section of an inverted "convex"-shaped structure with a larger upper portion and a smaller lower portion.

[0015] The beneficial effects of the present invention are as follows: the installation position of the plug pin is away from the electrolyte chamber on the shell, so that the two are not connected; the plug pin is separately installed on the bottom of the first groove on the protrusion outside the shell and is sealed by a pressure cover. This arrangement allows ultrasonic connection between the upper cover and the shell to be performed first, and then connection between the metal conductive wire and the plug pin to be performed, so that the ultrasonic connection between the upper cover and the shell will not affect the metal conductive wire and the plug pin, such as loosening of the plug pin, damage to the connection between the metal conductive wire and the plug pin, and damage to the metal conductive wire itself. This can solve the problems of plug pin leakage and metal conductive wire damage caused by ultrasonic connection between the upper cover and the shell in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of an embodiment of a lead-free oxygen sensor of the present invention;

[0017] Figure 2 yes Figure 1 Schematic diagram of the internal structure of the lead-free oxygen sensor;

[0018] Figure 3 yes Figure 1 Schematic diagram of the structure after removing the gland;

[0019] Figure 4 yes Figure 1 Schematic diagram of the structure of the middle pressure cover. DETAILED DESCRIPTION

[0020] To facilitate understanding of the present invention, the present invention is described in more detail below with reference to the accompanying drawings and specific embodiments. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0021] It should be noted that, unless otherwise defined, the technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art in the field of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0022] An embodiment of a lead-free oxygen sensor of the present utility model is as follows Figures 1-4 As shown, it includes a shell 1, and an electrochemical reaction layer (not shown in the figure) is arranged inside the shell. In this embodiment, the electrochemical reaction layer (the reaction of the sensor is carried out in this part), specifically, the electrochemical reaction layer includes a working electrode, a reference electrode, a counter electrode, a liquid-absorbing cotton and an airtight diaphragm. The liquid-absorbing cotton is used to absorb the electrolyte, and the airtight diaphragm is used to isolate the gas. The electrochemical reaction layer belongs to the prior art and is not an improved part of the present invention. Therefore, this part is no longer described in detail in this embodiment. The shell 1 includes an upper cover 2 and a shell 3. The upper cover is provided with an air inlet 4, and an electrolyte cavity 8 is provided in the shell. The electrochemical reaction layer is arranged in the electrolyte cavity and is located below the air inlet. The shell is provided with a liquid injection port 11 connected to the electrolyte cavity, and the shell is also provided with an air outlet 9. A raised platform is provided in the electrolyte chamber, an air outlet is provided on the platform and connects the outside with the electrolyte chamber, the electrochemical reaction layer is located above the platform, and the gas generated by the reaction is discharged through the air outlet. At this time, a placement groove 10 for placing the waterproof breathable membrane is provided above the platform.

[0023] The outer wall of the housing 3 is provided with a protrusion 5, and a first groove 12 with an upward opening is provided on the protrusion. The bottom of the first groove is provided with a pin mounting hole 19 for mounting a pin 7, which is connected to the corresponding electrode through a metal conductive wire. In this embodiment, the number of pins is three, and correspondingly, the number of pin mounting holes is also three. The housing is provided with a through hole 13 for the metal conductive wire to pass through. After the metal conductive wire passes through the through hole, the through hole is sealed to prevent the electrolyte from passing through. Specifically, the through hole can be sealed with a sealant such as epoxy glue. The first groove 12 is equipped with a pressure cover 6, which is used to seal and protect the metal conductive wire and the pin. The outer wall of the housing is provided with a second groove 18, and the through hole 13 is provided at the bottom of the second groove.

[0024] In this embodiment, a channel 17 is formed between the gland and the outer wall of the housing for the metal conductive wire connected to the pins to pass through. Specifically, a gap is formed between the side of the gland facing the housing and the outer wall of the housing to form the aforementioned channel. The gland 6 includes a first gland portion 14 that blocks the first and second grooves. The gland also includes a second gland portion 15 that extends into the first groove to press against and secure the pins after they are connected to the metal conductive wires. In this embodiment, the first and second gland portions 14, 15 form an inverted "convex"-shaped structure in longitudinal cross-section, with the top larger and the bottom smaller. The longitudinal cross-section in this embodiment refers to a section taken along the vertical direction shown in the accompanying drawings.

[0025] During use, the three pins are placed into the first groove. The pins are then pressed into the pin mounting holes with a pressure cap, and the pressure cap is removed. The trimmed metal conductive wire is then threaded through the through-holes, leaving a corresponding length of metal conductive wire inside the housing and in the first groove. The sensor is then assembled by aligning the electrochemical reaction layer with the metal conductive wire. Ultrasonication is then performed to connect the upper cover to the housing. After the ultrasonication is complete, the through-holes on the side of the housing are sealed with epoxy glue. This seal prevents electrolyte from escaping through the through-holes during the subsequent injection process and reduces damage to the metal conductive wire caused by the ultrasonication. After the epoxy glue dries, an appropriate amount of electrolyte is injected through the injection port at the bottom of the housing. This biases the internal electrodes to react with oxygen. Finally, the external structure of the injection port is melted, sealing the injection port and completing the complete seal. Finally, the metal conductive wire is spot welded to the pins, one-to-one. This prevents excessive ultrasonic energy from damaging the metal conductive wire at the pins. After the metal conductive wire is spot-welded, an appropriate amount of epoxy glue is injected into the spot weld to secure it. The gland is then installed. This protects the metal conductive wire and the pins, and also adds aesthetic appeal. The gland and the first groove can be connected by a tight fit, adhesive bonding, or other conventional connection methods as needed.

[0026] In the above description of this specification, unless otherwise expressly specified or limited, terms such as "fixed," "mounted," "connected," or "connected" should be understood broadly. For example, the term "connected" can refer to a fixed connection, a removable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal connection between two components or the interaction between two components. Therefore, unless otherwise expressly defined in this specification, those skilled in the art can understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0027] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "up", "down", "front", "back", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "center", "longitudinal", "lateral", "clockwise" or "counterclockwise", etc., which indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings of this specification, and are only for the purpose of facilitating the explanation of the scheme of the utility model and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the utility model.

[0028] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinal numbers are used for descriptive purposes only and should not be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, "plurality" means at least two, such as two, three or more, etc., unless otherwise clearly specified.

[0029] In other embodiments of the present invention, the channel between the gland and the outer wall of the shell for the metal conductive wire to pass through can also be formed by a wire groove opened on the side of the gland and / or the outer wall of the shell; on the premise of ensuring the fixation of the pin, the second part of the gland may also be not provided on the gland, and in this case the gland is connected to the first groove or the outer wall of the shell by gluing.

[0030] The embodiment of the lead-free oxygen sensor housing of the present invention has the same structure as the housings in the above embodiments of the lead-free oxygen sensor, and will not be described in detail here.

Claims

1. A lead-free oxygen sensor housing, comprising an upper cover and a shell, wherein the upper cover is provided with an air inlet, an electrolyte chamber is provided within the shell, a liquid injection port communicating with the electrolyte chamber is provided on the shell, and an air outlet is also provided on the shell, characterized in that: A protrusion is provided on the outer wall of the shell, a first groove is provided on the protrusion, a pin mounting hole is provided on the bottom of the first groove, a through hole is provided on the shell for the metal conductive wire connected to the pin to pass through, and the first groove is equipped with a pressure cover, which is used to seal and protect the metal conductive wire and the pin.

2. The lead-free oxygen sensor housing according to claim 1, characterized in that: A channel for a metal conductive wire connected to the pin to pass through is provided between the pressure cover and the outer side wall of the shell.

3. The lead-free oxygen sensor housing according to claim 2, characterized in that: A second groove is provided on the outer side wall of the shell, a through hole is provided on the bottom of the second groove, and a gap is provided between the side of the pressure cover facing the shell and the outer side wall of the shell to form the above-mentioned channel.

4. The lead-free oxygen sensor housing according to claim 3, characterized in that: The pressure cover includes a first pressure cover portion for blocking the first groove and the second groove, and also includes a second pressure cover portion extending into the first groove for pressing and fixing the pin connected to the metal conductive wire.

5. The lead-free oxygen sensor housing according to claim 4, characterized in that: The first part of the pressure cover and the second part of the pressure cover form an inverted "convex" shaped structure with a longitudinal section that is larger at the top and smaller at the bottom.

6. A lead-free oxygen sensor comprising a housing, an electrochemical reaction layer disposed within the housing, the electrochemical reaction layer comprising a working electrode, a reference electrode, and a counter electrode, the housing comprising an upper cover and a shell, the upper cover being provided with an air inlet, the shell being provided with an electrolyte chamber, the shell being provided with a liquid injection port communicating with the electrolyte chamber, and the shell being provided with an air outlet, characterized in that: A protrusion is provided on the outer wall of the shell, and a first groove is provided on the protrusion. A pin mounting hole is provided on the bottom of the first groove for installing the pin; the pin is connected to the corresponding electrode through a metal conductive wire, and a through hole is provided on the shell for the metal conductive wire to pass through. After the metal conductive wire passes through the through hole, the through hole is sealed to prevent the electrolyte from passing through; the first groove is equipped with a pressure cover, which is used to seal and protect the metal conductive wire and the pin.

7. The lead-free oxygen sensor according to claim 6, characterized in that: A channel for a metal conductive wire connected to the pin to pass through is provided between the pressure cover and the outer side wall of the shell.

8. The lead-free oxygen sensor according to claim 7, characterized in that: A second groove is provided on the outer side wall of the shell, a through hole is provided on the bottom of the second groove, and a gap is provided between the side of the pressure cover facing the shell and the outer side wall of the shell to form the above-mentioned channel.

9. The lead-free oxygen sensor according to claim 8, characterized in that: The pressure cover includes a first pressure cover portion for blocking the first groove and the second groove, and also includes a second pressure cover portion extending into the first groove for pressing and fixing the pin connected to the metal conductive wire.

10. The lead-free oxygen sensor according to claim 9, characterized in that: The first part of the pressure cover and the second part of the pressure cover form an inverted "convex" shaped structure with a longitudinal section that is larger at the top and smaller at the bottom.

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