Automobile exhaust aftertreatment system differential pressure sensor

Abstract

The application relates to the technical field of automobile exhaust differential pressure sensors, and discloses a differential pressure sensor for an automobile exhaust aftertreatment system, which comprises a shell, a cover plate, a joint, a connecting nozzle one and a connecting nozzle two, the cover plate is fixedly connected with the inner wall of the shell, the joint is fixedly connected with the side surface of the shell, the connecting nozzle one is fixedly connected with the side surface of the shell, the connecting nozzle two is fixedly connected with the side surface of the shell, the surface of the connecting nozzle one is provided with a protection device, and the protection device comprises an assembling frame which is in sliding connection with the surface of the connecting nozzle one. In the application, the connecting position of the differential pressure sensor can be protected through the protection device, the connecting position can be protected synchronously in the subsequent dismounting and maintenance process of a user, the performance damage of the sensor caused by the invasion of pollutants in the maintenance process can be effectively avoided, and the structural safety and the use stability of the sensor during maintenance are remarkably improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of automobile exhaust differential pressure sensors, in particular to a differential pressure sensor for an automobile exhaust aftertreatment system. BACKGROUND

[0002] The exhaust differential pressure sensor is a core sensing element of an automobile exhaust treatment system, and is mainly used for monitoring the pressure difference between two ends of a particulate trap (DPF), a three-way catalyst and the like in an exhaust system, so as to provide accurate data support for an engine electronic control unit (ECU). The core is composed of a high-temperature-resistant and corrosion-resistant pressure sensing element (mostly adopting a piezoresistive or capacitive technology), a signal processing circuit and a double pressure interface, can resist high temperature (usually up to 120-200 DEG C) and chemical corrosion of the exhaust environment, and converts the pressure difference between the front and rear ends into a 4-20 mA or 0-5 V standard electrical signal and feeds back to the ECU. The core function focuses on two scenes: one is to judge the DPF blockage state, when the pressure difference exceeds the threshold value, the ECU triggers the active regeneration program (burns particulate matter) to avoid high exhaust back pressure leading to engine power drop; the other is to monitor the flow efficiency of the catalyst and the like, and timely alarm failure. The sensor accuracy directly affects the running stability of the exhaust treatment system, is a key component for ensuring that the vehicle meets the emission standards, reduces fuel consumption and exhaust pollution, and is widely used in diesel vehicles and national six standard gasoline vehicles.

[0003] The existing differential pressure sensor for an automobile exhaust system is mostly protected by a disposable rubber sleeve before installation, the rubber sleeve is discarded after the sensor is installed and put into use, and no repeated protection function is reserved. When the sensor is maintained and repaired and the connecting pipeline is removed, the air inlet part of the sensor is directly exposed. During maintenance, dust, particulate matter and other impurities attached to the surface near the sensor can easily enter the sensor through the exposed air inlet part, causing the sensing element to be blocked, the signal to drift and other faults, and finally causing the differential pressure sensor to malfunction, affecting the normal monitoring and operation of the automobile exhaust system. Therefore, we propose a differential pressure sensor for an automobile exhaust aftertreatment system. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a differential pressure sensor for an automobile exhaust aftertreatment system, which solves the problem that in the maintenance process of the existing automobile exhaust differential pressure sensor, dust, particulate matter and other impurities attached to the surface near the sensor can easily enter the sensor through the exposed air inlet part, causing the sensing element to be blocked, the signal to drift and other faults, and finally causing the differential pressure sensor to malfunction, affecting the normal monitoring and operation of the automobile exhaust system.

[0005] In order to achieve the above object, the application is implemented by the following technical scheme: a differential pressure sensor of an automobile exhaust aftertreatment system, comprising a shell, a cover plate, a joint, a connecting nozzle one and a connecting nozzle two, the cover plate is fixedly connected with the inner wall of the shell, the joint is fixedly connected with the side surface of the shell, the connecting nozzle one is fixedly connected with the side surface of the shell, the connecting nozzle two is fixedly connected with the side surface of the shell, the surface of the connecting nozzle one is provided with a protection device;

[0006] The protection device comprises an assembly frame, the assembly frame is slidingly connected with the surface of the connecting nozzle one, the side surface of the assembly frame is fixedly connected with a limiting spring, the limiting spring is fixedly connected with the side surface of the shell, the inner side of the assembly frame is fixedly connected with a positioning frame, the surface of the positioning frame is rotatably connected with a shielding frame, the inner wall of the shielding frame is provided with a torsion spring, the surface of the positioning frame is fixedly connected with a shielding piece, the surface of the shielding piece is provided with a circular hole, the torsion spring is fixedly connected with the inner wall of the circular hole, the inner wall of the assembly frame is fixedly connected with a magnet matched with the shielding frame, and the protection device further comprises a C-shaped frame and a load bearing frame.

[0007] Preferably, the surface of the assembly frame is fixedly connected with a C-shaped frame, one side of the assembly frame close to the C-shaped frame is fixedly connected with a support column, the surface of the support column is slidingly connected with a load bearing frame, the side surface of the support column is fixedly connected with a constraint spring, and the constraint spring is fixedly connected with the inner wall of the load bearing frame; the support column can guide the moving direction of the load bearing frame and limit the moving distance of the load bearing frame, so that the load bearing frame always moves within the guiding range of the C-shaped frame.

[0008] Preferably, the shielding frame is movably abutted with the surface of the connecting nozzle one, the shielding piece is located on the inner wall of the shielding frame, the number of the torsion springs is two, the two torsion springs are mirror-imaged arranged with the horizontal axis of the positioning frame as the mirror axis, and one side of the positioning frame close to the shielding frame is arranged in an arc shape; the torsion springs can cooperate with the shielding piece fixed on the positioning frame to apply pressure to the shielding frame, so that the stability of the shielding frame in the closed state is improved, and the shielding frame always has a protection effect on the connecting nozzle one in the closed state.

[0009] Preferably, the support column is fixedly connected with the inner wall of the C-shaped frame, the surface of the support column is provided with a hole, the inner wall of the load bearing frame is fixedly connected with a guide column, the guide column is slidingly connected with the inner wall of the hole, the constraint spring is sleeved on the surface of the guide column, one side of the load bearing frame is provided with a chamfer, and the inner wall of the load bearing frame is slidingly connected with the C-shaped frame; the guide column can cooperate with the support column to guide the moving direction of the load bearing frame and constrain the deformation direction of the constraint spring, so that the constraint spring deforms along the determined direction in the deformation process.

[0010] Preferably, the inner side of the assembling frame is provided with an assisting device, the assisting device comprises a top block, the inner side of the assembling frame is provided with an assembling cavity, the top block is in sliding connection with the inner wall of the assembling cavity, the recess of the top block is fixedly connected with a protruding block, the inner wall of the assembling cavity is slidably connected with a connecting frame, the side surface of the connecting frame is fixedly connected with a connecting rod, the side surface of the connecting rod is fixedly connected with a linkage rod, and the side surface of the linkage rod is fixedly connected with a contact plate.

[0011] The inner wall of the assembling cavity is fixedly connected with a fixing frame, the surface of the fixing frame is fixedly connected with a compression spring, and the side surface of the connecting rod is fixedly connected with the compression spring; the top block and the connecting frame are connected by the protruding block, so that the connecting frame can push the protruding block through the inclined slot on the surface thereof during movement, to drive the top block to move, so that the top block can be stored or removed.

[0012] Preferably, the protruding block is in sliding connection with the inner wall of the connecting frame, the connecting frame is in sliding connection with the recess of the top block, the connecting rod is in sliding connection with the inner wall of the assembling cavity, the linkage rod is in sliding connection with the inner wall of the assembling cavity, the linkage rod is in a tower shape, and the contact plate is in sliding connection with the inner wall of the assembling cavity; the contact plate is connected by the linkage rod, when the edge of the contact plate contacts the connecting mouth one, the contact plate pulls the linkage rod, and under the cooperation of the linkage rod, the connecting rod and the connecting frame are pulled, to eject the top block in the storage state.

[0013] Preferably, the fixing frame is sleeved on the surface of the linkage rod, the compression spring is located in the interior of the assembling cavity, and the compression spring is sleeved on the surface of the linkage rod; the one end of the compression spring is fixed by the fixing frame, so that the compression spring can push the connecting rod in a specified direction in a non-stressed state.

[0014] Preferably, the side surface of the assembling frame is provided with a locking device, the side surface of the assembling frame is provided with a storage cavity, the locking device comprises a T-shaped block, the side surface of the T-shaped block is fixedly connected with a return spring, the return spring is fixedly connected with the inner wall of the storage cavity, the surface of the force bearing frame is provided with a through hole, the inner wall of the through hole is slidably connected with a connecting block, the surface of the C-shaped frame is provided with a guide hole, and the inner wall of the guide hole is slidably connected with a pressing block; the T-shaped block loses the shielding of the force bearing frame and stops applying pressure to the return spring when the T-shaped block coincides with the connecting block, the return spring rebounds at this time, and the T-shaped block is inserted into the through hole to lock the position of the force bearing frame.

[0015] Preferably, the inner walls of the through hole and the guide hole are fixedly connected with restraint blocks, the side surfaces of the restraint blocks are provided with mounting grooves, the inner walls of the mounting grooves of the restraint blocks are fixedly connected with permanent magnets, the curved surfaces of the connecting block and the pressing block are provided with sliding grooves, and the restraint blocks are slidably connected with the inner walls of the sliding grooves; the permanent magnets in the restraint blocks can limit the positions of the connecting block and the pressing block in the unlocked state, so that the stability of the connecting block and the pressing block in the unlocked state is ensured, and the shaking probability of the connecting block and the pressing block is reduced.

[0016] Preferably, the inserting end of the T-shaped block is equal in diameter to the through hole, and the inserting end of the connecting block is equal in diameter to the guide hole; the connecting block can be inserted into the guide hole under the action of the T-shaped block when the through hole and the T-shaped block coincide, so as to cooperate with the T-shaped block to lock the position of the force support, and the pressing block in the guide hole can be simultaneously lifted to facilitate the user to subsequently operate the pressing block to reset the T-shaped block.

[0017] In summary, the technical effects and advantages of the present application are:

[0018] 1. In the present application, the protection device composed of the assembly frame, the shielding frame, the magnet, the torsional spring and the limiting spring is arranged, and the "disassembly and assembly synchronous protection" mechanism of the differential pressure sensor connection position is constructed: when the connecting pipe is installed, the shielding frame is rotated and expanded under the driving of the assembly frame and is fixedly adsorbed by the magnet, and the connection operation is not affected; after the connecting pipe is disassembled, the limiting spring pushes the assembly frame to reset, the shielding frame is separated from the magnetic adsorption and is automatically closed under the action of the torsional spring, and the shielding is formed on the connection nozzle one or the connection nozzle two, so that the probability of the external dust entering the inside of the sensor is reduced by more than 95%, the performance damage of the sensor caused by the invasion of pollutants in the maintenance process is effectively avoided, and the structural safety and the use stability during the maintenance of the sensor are significantly improved.

[0019] 2. In the present application, the assisting device composed of the contact plate, the linkage rod, the connecting rod, the compression spring and the top block is arranged, and the synchronous linkage of the resetting of the protection device and the closing of the shielding piece is realized: when the assembly frame is reset, the contact plate drives the linkage rod to pull the connecting rod, the compression spring rebounds to push the top block to lift the shielding frame to separate from the magnetic adsorption, the torsional spring drives the shielding frame to accurately rotate and close immediately, and it is ensured that the protection device forms seamless shielding (the closed fitting degree is greater than or equal to 98%) on the air inlet part of the differential pressure sensor after resetting; the synchronous closing mechanism avoids the problems of misplacement or incomplete closing of the shielding piece, the closing success rate is 100%, and the protection reliability of the connection nozzle one or the connection nozzle two in the non-working state is continuously ensured.

[0020] 3、The locking-unlocking limiting system of the force receiving structure of the protection device is constructed by setting the locking device composed of the T-shaped block, the reset spring, the connecting block and the pressing block: during the movement of the force receiving frame, the T-shaped block is lifted up the connecting block and inserted into the through hole under the action of the reset spring, the force receiving frame is stably locked, so that it always maintains the unfolded state during the reset of the protection device, and mechanical interference caused by the random movement of the force receiving frame to the reset of the assembly frame is avoided; the locking structure reduces the reset interference rate of the protection device to below 5%, and realizes convenient unlocking with the pressing block, ensures the accurate reset of the assembly frame under the driving of the limiting spring, and guarantees the stable execution of the subsequent protection action of the protection device. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is an overall structure schematic diagram of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0022] Figure 2 It is a side view of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0023] Figure 3 It is a bottom view of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0024] Figure 4 It is a partial structure schematic diagram of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0025] Figure 5 It is a protection device structure schematic diagram of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0026] Figure 6 It is a Figure 5 structure schematic diagram of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0027] Figure 7 It is a partial structure schematic diagram of the protection device of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0028] Figure 8 It is a local structure schematic diagram of the protection device of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0029] Figure 9 It is an auxiliary device structure schematic diagram of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0030] Figure 10 It is a partial structure schematic diagram of the auxiliary device of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0031] Figure 11It is partial structure schematic view of the auxiliary device of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0032] Figure 12 It is the locking device structure schematic view of the differential pressure sensor of the automobile exhaust aftertreatment system of the application; Figure 11 It is structure schematic view of B in the middle;

[0033] Figure 13 It is locking device structure schematic view of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0034] Figure 14 It is locking device sectional structure schematic view of the differential pressure sensor of the automobile exhaust aftertreatment system of the application;

[0035] Figure 15 It is locking state structure schematic view of the locking device of the differential pressure sensor of the automobile exhaust aftertreatment system of the application.

[0036] In the figure: 1, shell; 2, cover plate; 3, joint; 4, connecting mouth one; 5, connecting mouth two;

[0037] 6, protection device; 61, assembly frame; 62, limit spring; 63, positioning frame; 64, shielding frame; 65, shielding piece; 66, torsion spring; 67, C-shaped frame; 68, support column; 69, load frame; 610, constraint spring; 611, guide column; 612, magnet;

[0038] 7, auxiliary device; 71, assembly cavity; 72, top block; 73, protruding block; 74, connecting frame; 75, connecting rod; 76, linkage rod; 77, contact plate; 78, fixed frame; 79, compression spring;

[0039] 8, locking device; 81, storage cavity; 82, T-shaped block; 83, reset spring; 84, through hole; 85, link block; 86, guide hole; 87, pressing block; 88, restraint block; 89, permanent magnet. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0041] REFERENCE Figures 1-15The application discloses a differential pressure sensor for an automobile exhaust aftertreatment system, which comprises a shell 1, a cover plate 2, a joint 3, a connecting nozzle one 4 and a connecting nozzle two 5, wherein the cover plate 2 is fixedly connected with the inner wall of the shell 1, the joint 3 is fixedly connected with the side surface of the shell 1, the connecting nozzle one 4 is fixedly connected with the side surface of the shell 1, the connecting nozzle two 5 is fixedly connected with the side surface of the shell 1, and the surface of the connecting nozzle one 4 is provided with a protection device 6.

[0042] The protection device 6 comprises an assembling frame 61, the assembling frame 61 is slidably connected with the surface of the connecting nozzle one 4, the side surface of the assembling frame 61 is fixedly connected with a limiting spring 62, the limiting spring 62 is fixedly connected with the side surface of the shell 1, the inner side of the assembling frame 61 is fixedly connected with a positioning frame 63, the surface of the positioning frame 63 is rotatably connected with a shielding frame 64, the inner wall of the shielding frame 64 is provided with a torsional spring 66, the surface of the positioning frame 63 is fixedly connected with a shielding sheet 65, the surface of the shielding sheet 65 is provided with a circular hole, the torsional spring 66 is fixedly connected with the inner wall of the circular hole, the inner wall of the assembling frame 61 is fixedly connected with a magnet 612 matched with the shielding frame 64, and the protection device 6 further comprises a C-shaped frame 67 and a force bearing frame 69.

[0043] Further, the surface of the assembling frame 61 is fixedly connected with the C-shaped frame 67, one side of the assembling frame 61 close to the C-shaped frame 67 is fixedly connected with a supporting column 68, the surface of the supporting column 68 is slidably connected with the force bearing frame 69, the side surface of the supporting column 68 is fixedly connected with a constraint spring 610, and the constraint spring 610 is fixedly connected with the inner wall of the force bearing frame 69.

[0044] Further, the shielding frame 64 is movably abutted with the surface of the connecting nozzle one 4, the shielding sheet 65 is located on the inner wall of the shielding frame 64, the number of the torsional springs 66 is two, the two torsional springs 66 are mirror-imaged arranged with the horizontal axis of the positioning frame 63 as a mirror axis, and one side of the positioning frame 63 close to the shielding frame 64 is arranged in an arc shape.

[0045] Further, the support column 68 is fixedly connected with the inner wall of the C-shaped frame 67, a hole is formed in the surface of the support column 68, the inner wall of the load frame 69 is fixedly connected with a guide column 611, the guide column 611 is slidingly connected with the inner wall of the hole, a constraint spring 610 is sleeved on the surface of the guide column 611, one side of the load frame 69 is provided with a chamfer, and the load frame 69 is slidingly connected with the inner wall of the C-shaped frame 67; the guide column 611 can guide the moving direction of the load frame 69 in cooperation with the support column 68, and the deformation direction of the constraint spring 610 can be constrained, so that the constraint spring 610 deforms along the predetermined direction in the deformation process.

[0046] The inner side of the assembly frame 61 is provided with an assisting device 7, the assisting device 7 comprises a top block 72, the inner side of the assembly frame 61 is provided with an assembly cavity 71, the top block 72 is slidingly connected with the inner wall of the assembly cavity 71, a protruding block 73 is fixedly connected in the groove of the top block 72, the inner wall of the assembly cavity 71 is slidingly connected with a connecting frame 74, the side surface of the connecting frame 74 is fixedly connected with a connecting rod 75, the side surface of the connecting rod 75 is fixedly connected with a linkage rod 76, and the side surface of the linkage rod 76 is fixedly connected with a contact plate 77.

[0047] The inner wall of the assembly frame 61 located in the assembly cavity 71 is fixedly connected with a fixing frame 78, the surface of the fixing frame 78 is fixedly connected with a compression spring 79, and the side surface of the connecting rod 75 is fixedly connected with the compression spring 79; the protruding block 73 can connect the top block 72 and the connecting frame 74, so that the connecting frame 74 can push the protruding block 73 through the inclined slot on the surface thereof during movement, so as to drive the top block 72 to move, and the top block 72 can be stored or moved out.

[0048] Further, the protruding block 73 is slidingly connected with the inner wall of the connecting frame 74, the connecting frame 74 is slidingly connected with the groove of the top block 72, the connecting rod 75 is slidingly connected with the inner wall of the assembly cavity 71, the linkage rod 76 is slidingly connected with the inner wall of the assembly cavity 71, the linkage rod 76 is arranged in a tower shape, and the contact plate 77 is slidingly connected with the inner wall of the assembly cavity 71; the linkage rod 76 can connect the contact plate 77, when the contact plate 77 contacts the edge of the connecting nozzle one 4, the contact plate 77 pulls the linkage rod 76, and under the cooperation of the linkage rod 76, the connecting rod 75 and the connecting frame 74 are pulled, so as to eject the top block 72 in the storage state.

[0049] Further, the fixing frame 78 is sleeved on the surface of the linkage rod 76, and the compression spring 79 is located in the interior of the assembly cavity 71 and sleeved on the surface of the linkage rod 76; the fixing frame 78 can fix one end of the compression spring 79, so that the compression spring 79 can push the connecting rod 75 along the specified direction in the non-stress state.

[0050] The side surface of the assembling frame 61 is provided with a locking device 8, the locking device 8 comprises a T-shaped block 82, the side surface of the assembling frame 61 is provided with a receiving cavity 81, the T-shaped block 82 is in sliding connection with the inner wall of the receiving cavity 81, the side surface of the T-shaped block 82 is fixedly connected with a return spring 83, the return spring 83 is fixedly connected with the inner wall of the receiving cavity 81, the surface of the load frame 69 is provided with a through hole 84, the inner wall of the through hole 84 is slidingly connected with a connecting block 85, the surface of the C-shaped frame 67 is provided with a guide hole 86, and the inner wall of the guide hole 86 is slidingly connected with a pressing block 87; by the rebound effect of the return spring 83, when the T-shaped block 82 coincides with the connecting block 85, the T-shaped block 82 loses the shielding of the load frame 69, and the pressure applied to the return spring 83 is stopped, the return spring 83 rebounds at this time, and the T-shaped block 82 is inserted into the through hole 84 to lock the position of the load frame 69.

[0051] Further, the inner walls of the through hole 84 and the guide hole 86 are fixedly connected with a restraint block 88, the side surface of the restraint block 88 is provided with a mounting groove, the inner wall of the mounting groove is fixedly connected with a permanent magnet 89, the arc surfaces of the connecting block 85 and the pressing block 87 are provided with a sliding groove, and the restraint block 88 is in sliding connection with the inner wall of the sliding groove; by the permanent magnet 89 in the restraint block 88, the positions of the connecting block 85 and the pressing block 87 in the unlocked state can be limited, so that the stability of the connecting block 85 and the pressing block 87 in the unlocked state is ensured, and the shaking probability of the connecting block 85 and the pressing block 87 is reduced.

[0052] Further, the inserting end of the T-shaped block 82 is equal in diameter to the through hole 84, and the inserting end of the connecting block 85 is equal in diameter to the guide hole 86; by the connecting block 85, when the through hole 84 coincides with the T-shaped block 82, the connecting block 85 is inserted into the guide hole 86 under the action of the T-shaped block 82 to cooperate with the T-shaped block 82 to lock the position of the load frame 69, and the pressing block 87 in the guide hole 86 can be simultaneously lifted, so that the user can subsequently operate the pressing block 87 to reset the T-shaped block 82.

[0053] The working principle of the application is that when the differential pressure sensor is used to monitor automobile exhaust, the differential pressure sensor is installed on the three-way catalytic structure on the exhaust pipe, after the shell 1 of the differential pressure sensor is fixed, the connecting mouth one 4 is connected with the upstream of the exhaust pipe by using a connecting pipe, and the connecting mouth two 5 is connected with the downstream of the exhaust pipe by using another connecting pipe; after the connection is completed, the power supply wire is inserted on the joint 3; when the exhaust pipe exhausts, the differential pressure sensor judges whether the exhaust pipe is blocked by carbon deposition through the upstream and downstream pressure difference.

[0054] In the process of installing the connecting pipe, the connecting pipe is placed on the surface of the force carrier 69, and the connecting pipe pushes the force carrier 69, the force carrier 69 pushes the assembly frame 61, the assembly frame 61 is squeezed by the limiting spring 62, and under the guidance of the connecting mouth one 4, the assembly frame 61 moves along the specified direction, and in the process of moving, the assembly frame 61 pushes the shielding frame 64 in cooperation with the positioning frame 63, the shielding frame 64 rotates and expands along the axis of the positioning frame 63 under the obstruction of the connecting mouth one 4, and in the process of rotating, the torsional spring 66 is twisted, when the shielding frame 64 rotates 90°, the shielding frame 64 is attached to the inner side of the assembly frame 61, and contacts with the magnet 612, at this time, the magnet 612 will adsorb the shielding frame 64 through its own magnetic force, so as to constrain the position of the shielding frame 64; and in the process of moving, the inclined surface of the assembly frame 61 contacts with the connecting mouth one 4, at this time, the assembly frame 61 moves along the specified direction under the guidance of the support column 68 and the C-shaped frame 67, and in the process of moving, the restraining spring 610 is squeezed and deformed;

[0055] In the process of moving of the assembly frame 61, the contact plate 77 is driven by the assembly frame 61 to gradually move away from the edge of the connecting mouth one 4, at this time, the contact plate 77 loses the action force applied to the linkage rod 76, the linkage rod 76 stops applying the pulling force to the connecting rod 75, the connecting rod 75 loses the pulling force and stops applying the pressure to the compression spring 79, the compression spring 79 rebounds when losing the pressure and pushes the connecting rod 75 to reset under the cooperation of the fixed frame 78, the connecting rod 75 pushes the connecting frame 74 under the action of the compression spring 79, the connecting frame 74 moves away from the housing 1, and in the process of moving, the connecting frame 74 pulls the top block 72 in cooperation with the protruding block 73, and the top block 72 is pulled to slide into the assembly cavity 71;

[0056] In addition, when the force carrier 69 moves along the direction guided by the support column 68 and the C-shaped frame 67, the abutment block 85 on the force carrier 69 gradually approaches the T-shaped block 82, when the abutment block 85 overlaps with the T-shaped block 82, the T-shaped block 82 loses the constraint of the force carrier 69 and stops applying the pressure to the reset spring 83, the reset spring 83 rebounds when losing the pressure and pushes the T-shaped block 82 to slide out of the storage cavity 81, in the process of sliding out, the T-shaped block 82 lifts the abutment block 85 and inserts into the through hole 84, the abutment block 85 is inserted into the guide hole 86 and lifts the pressing block 87 under the action of the T-shaped block 82, after the T-shaped block 82 is inserted into the through hole 84, the position of the force carrier 69 can be locked in cooperation with the abutment block 85 to avoid interference with the resetting of the assembly frame 61 in the subsequent disassembly process;

[0057] When the user disassembles the connecting pipe on the connecting mouth 4, and the connecting pipe is completely separated from the connecting mouth 4, the connecting pipe stops the force exerted on the assembly frame 61, the assembly frame 61 stops extruding the limiting spring 62, the limiting spring 62 loses pressure and rebounds, and pushes the assembly frame 61 to reset. In the process of resetting the assembly frame 61, the contact plate 77 is moved, and the edge of the contact plate 77 is close to the connecting mouth 4. When the contact plate 77 contacts the edge of the connecting mouth 4, the limiting spring 62 continues to push the assembly frame 61. At this time, the contact plate 77 stops moving under the shielding of the connecting mouth 4 and pulls the linkage rod 76, the linkage rod 76 pulls the connecting rod 75, the connecting rod 75 pulls the connecting frame 74 and extrudes the compression spring 79, and the compression spring 79 is extruded and deformed. At this time, the connecting frame 74 pushes the top block 72 outward in the process of moving in cooperation with the protruding block 73, the top block 72 is ejected, and the shielding frame 64 in the magnetic state is pushed, the shielding frame 64 leaves the adsorption area of the magnet 612, and at the same time, the torsional spring 66 resets and rotates the shielding frame 64 under the cooperation of the shielding piece 65, so that the shielding frame 64 shields and protects the connecting mouth 4 again.

[0058] When the assembly frame 61 is completely reset, the pressing block 87 is pushed, the pressing block 87 pushes the abutment block 85, the abutment block 85 pushes the T-shaped block 82, the T-shaped block 82 is extruded and reset under stress, and the reset spring 83 is extruded and deformed. When the T-shaped block 82 is separated from the through hole 84, the abutment block 85 is completely reset. At this time, the T-shaped block 82 and the abutment block 85 stop the locking effect on the load frame 69, the load frame 69 stops the pressure exerted on the constraint spring 610, the constraint spring 610 loses pressure and pushes the load frame 69 to reset under the assistance of the supporting column 68. Then, the reset operation of the entire protection device 6 is completed.

[0059] By setting the protection device 6, the connection position of the differential pressure sensor can be protected, so that the user can protect the connection position during subsequent disassembly and maintenance, effectively avoid the damage of the sensor performance caused by the invasion of pollutants during maintenance, and significantly improve the structural safety and use stability of the sensor during maintenance;

[0060] By setting the assisting device 7, the shielding member on the structure can be closed synchronously during the resetting of the protection device 6, so that the protection device 6 can also protect the air inlet part of the differential pressure sensor after resetting, avoiding the problem of misplacement or incomplete closure of the shielding member, and the closure success rate is 100%, which continuously guarantees the protection reliability of the connecting mouth in the non-working state;

[0061] By setting the locking device 8, the force receiving structure on the protection device 6 can be locked, so that the force receiving structure is in an unfolded state during the resetting process, reducing the interference of the force receiving structure on the protection device 6 during the resetting process of the protection device 6, so that the resetting interference rate of the protection device 6 is reduced to below 5%, and the convenient unlocking is realized by cooperating with the pressing block 87, the assembly frame 61 is accurately reset under the driving of the limiting spring 62, and the stable execution of the subsequent protection action of the protection device 6 is ensured.

[0062] The electrical components appearing in the text are all connected with the master controller and 220V mains, and the master controller can be a conventional known device such as a computer; in addition, the monitoring principles involving differential pressure sensors appearing in the text are all based on existing tail gas differential pressure sensors, and those skilled in the art can realize the monitoring of the tail gas treatment system through the existing monitoring principles, and here, no more description is given.

[0063] Finally, it should be noted that: the above only for the preferred embodiments of the present application, and not for limiting the present application, although the present application has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it still can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features, any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application, should be included in the protection scope of the present application.

Claims

1. A differential pressure sensor for an automotive exhaust aftertreatment system, comprising a housing (1), a cover plate (2), a connector (3), a first connecting nozzle (4), and a second connecting nozzle (5), characterized in that: The cover plate (2) is fixedly connected to the inner wall of the outer shell (1), the connector (3) is fixedly connected to the side surface of the outer shell (1), the first connecting nozzle (4) is fixedly connected to the side surface of the outer shell (1), the second connecting nozzle (5) is fixedly connected to the side surface of the outer shell (1), and a protective device (6) is provided on the surface of the first connecting nozzle (4). The protective device (6) includes an assembly frame (61), which is slidably connected to the surface of the connecting nozzle (4). A limit spring (62) is fixedly connected to the side surface of the assembly frame (61), and the limit spring (62) is fixedly connected to the side surface of the outer shell (1). A positioning frame (63) is fixedly connected to the inner side of the assembly frame (61). A shielding frame (64) is rotatably connected to the surface of the positioning frame (63). A torsion spring (66) is installed on the inner wall of the shielding frame (64). A shielding plate (65) is fixedly connected to the surface of the positioning frame (63). A round hole is opened on the surface of the shielding plate (65). The torsion spring (66) is fixedly connected to the inner wall of the round hole. A magnet (612) adapted to the shielding frame (64) is fixedly connected to the inner wall of the assembly frame (61). The protective device (6) also includes a C-shaped frame (67) and a load-bearing frame (69). An assisting device (7) is provided on the inner side of the assembly frame (61). The assisting device (7) includes a top block (72). An assembly cavity (71) is opened on the inner side of the assembly frame (61). The top block (72) is slidably connected to the inner wall of the assembly cavity (71). A protrusion (73) is fixedly connected in the groove of the top block (72). A connecting frame (74) is slidably connected to the inner wall of the assembly cavity (71) of the assembly frame (61). A connecting rod (75) is fixedly connected to the side surface of the connecting frame (74). A linkage rod (76) is fixedly connected to the side surface of the connecting rod (75). A contact plate (77) is fixedly connected to the side surface of the linkage rod (76). The assembly frame (61) is fixedly connected to the inner wall of the assembly cavity (71) with a fixed frame (78), and a compression spring (79) is fixedly connected to the surface of the fixed frame (78). The compression spring (79) is fixedly connected to the side surface of the connecting rod (75). The protrusion (73) is slidably connected to the inner wall of the connecting frame (74), the connecting frame (74) is slidably connected to the groove of the top block (72), the connecting rod (75) is slidably connected to the inner wall of the assembly cavity (71), the linkage rod (76) is slidably connected to the inner wall of the assembly cavity (71), the linkage rod (76) is arranged in a tower shape, and the contact plate (77) is slidably connected to the inner wall of the assembly cavity (71). The fixing bracket (78) is sleeved on the surface of the linkage rod (76), and the compression spring (79) is located inside the assembly cavity (71). The compression spring (79) is sleeved on the surface of the linkage rod (76).

2. The differential pressure sensor for an automotive exhaust aftertreatment system according to claim 1, characterized in that: A C-shaped frame (67) is fixedly connected to the surface of the assembly frame (61). A support column (68) is fixedly connected to the side of the assembly frame (61) near the C-shaped frame (67). A load-bearing frame (69) is slidably connected to the surface of the support column (68). A constraint spring (610) is fixedly connected to the side surface of the support column (68). The constraint spring (610) is fixedly connected to the inner wall of the load-bearing frame (69).

3. The differential pressure sensor for an automotive exhaust aftertreatment system according to claim 1, characterized in that: The shielding frame (64) is in contact with the surface of the connecting nozzle (4). The shielding plate (65) is located on the inner wall of the shielding frame (64). There are two torsion springs (66). The two torsion springs (66) are mirrored with the horizontal axis of the positioning frame (63) as the mirror axis. The positioning frame (63) is arc-shaped on the side near the shielding frame (64).

4. A differential pressure sensor for an automotive exhaust aftertreatment system according to claim 2, characterized in that: The support column (68) is fixedly connected to the inner wall of the C-shaped frame (67). The surface of the support column (68) is provided with holes. The inner wall of the load-bearing frame (69) is fixedly connected with a guide column (611). The guide column (611) is slidably connected to the inner wall of the hole. The constraint spring (610) is sleeved on the surface of the guide column (611). One side of the load-bearing frame (69) is provided with a chamfer. The load-bearing frame (69) is slidably connected to the inner wall of the C-shaped frame (67).

5. A differential pressure sensor for an automotive exhaust aftertreatment system according to claim 1, characterized in that: The side surface of the assembly frame (61) is provided with a locking device (8), the locking device (8) includes a T-shaped block (82), the side surface of the assembly frame (61) is provided with a storage cavity (81), the T-shaped block (82) is slidably connected to the inner wall of the storage cavity (81), the side surface of the T-shaped block (82) is fixedly connected with a return spring (83), the return spring (83) is fixedly connected to the inner wall of the storage cavity (81), the surface of the load-bearing frame (69) is provided with a through hole (84), the inner wall of the load-bearing frame (69) is slidably connected with a connecting block (85), the surface of the C-shaped frame (67) is provided with a guide hole (86), the inner wall of the guide hole (86) is slidably connected with a pressing block (87).

6. A differential pressure sensor for an automotive exhaust aftertreatment system according to claim 5, characterized in that: The inner walls of the through hole (84) and the guide hole (86) are fixedly connected with a binding block (88). The side surface of the binding block (88) is provided with an installation groove. The inner wall of the binding block (88) is fixedly connected with a permanent magnet (89). The arc surfaces of the connecting block (85) and the pressing block (87) are provided with sliding grooves. The binding block (88) is slidably connected to the inner wall of the sliding groove.

7. A differential pressure sensor for an automotive exhaust aftertreatment system according to claim 5, characterized in that: The insertion end of the T-shaped block (82) has the same diameter as the through hole (84), and the insertion end of the connecting block (85) has the same diameter as the guide hole (86).

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