CN221706851U - Clamp for detecting air tightness of plastic head of urea sensor and air tightness detection system - Google Patents

Abstract

The utility model discloses a fixture and an air tightness detection system for the air tightness detection of the plastic head of a urea sensor. The fixture includes a bottom plate, a mounting seat with a storage groove and two guide pillars are fixedly provided on the front side of the upper end of the bottom plate, the tops of the two guide pillars are fixedly connected through a top plate, a lifting cylinder with a piston rod vertically downward is installed on the top plate, a sliding plate is fixedly provided at the end of the piston rod of the lifting cylinder, and the sliding plates are slidably sleeved and installed on the two guide pillars at both ends, a plurality of vents are fixedly provided on the sliding plate that vertically penetrate the plate body, a trachea joint is provided at the upper end of the vent, and a plug-in section is provided at the lower end, and a plurality of push rod mechanisms for blocking the end of the connecting pipe head on the plastic head of the urea sensor are provided on the rear side of the bottom plate. The utility model fixture or detection system realizes the semi-automatic operation of the air tightness detection of the plastic head of the urea sensor, which helps to save labor costs, reduce the rate of manual misjudgment, and improve detection efficiency; it can also detect the sealing of each connecting pipe head one by one, and has good flexibility and applicability.

Description

Fixture and air tightness detection system for urea sensor plastic head

Technical Field

The utility model relates to the technical field of urea sensor detection equipment, in particular to a clamp and an airtightness detection system for airtightness detection of a plastic head of a urea sensor.

Background Art

Urea sensor is called urea transducer in English. It is a sensor that can convert the detected amount of urea into a usable output signal. It is commonly used in trucks and buses. The uses of urea sensor include: reducing NO _x in engine exhaust by more than 50%, which can effectively reduce environmental pollution; used to monitor the concentration and quality of urea in the SCR system of diesel engine emissions, and used to identify contaminated liquid in the SCR system; in addition, it also has many functions such as liquid level detection, heating, urea absorption, urea return, temperature measurement, urea filtration, balancing the air pressure inside and outside the urea tank, and urea concentration detection.

The urea sensor usually includes an injection-molded sensor head, a group of water circulation pipes, a pair of urea pipes, and a group of signal pipes are installed on the lower side of the sensor head, and a connecting pipe head and signal line identical to the pipes on the lower side of the sensor head are provided on the upper side. As shown in Figures 1 and 2, a plastic head of a urea sensor includes a plastic head body F, wherein the upper side of the plastic head body F is provided with a water inlet pipe head A, a water return pipe head B, a urea absorption pipe head C, a urea return pipe head D and a ventilation pipe head E facing one side thereof, and the lower side of the plastic head body F is provided with a water inlet hole a, a water return hole b, a urea absorption hole c, a urea return hole d and a ventilation hole e, wherein the water inlet hole a is connected with the water inlet pipe head A through the water inlet cavity inside the plastic head body F, the water return hole b is connected with the water return pipe head B through the water return cavity inside the plastic head body F, the urea absorption hole c is connected with the urea absorption pipe head C through the urea absorption cavity inside the plastic head body F, the urea return hole d is connected with the urea return pipe head D through the urea return cavity inside the plastic head body F, and the ventilation hole e is connected with the ventilation pipe head E through the ventilation channel inside the plastic head body F. Since the water inlet pipe head A, the water return pipe head B, the urea absorption pipe head C, the urea return pipe head D and the ventilation pipe head E are all installed on the plastic head body F through injection molding by adopting a post-assembly process, in order to ensure the air tightness of the installation positions of each pipe head on the urea sensor plastic head, it is necessary to perform an air tightness test on the urea sensor plastic head with the pipe heads installed.

In order to identify defective semi-finished products, the current common leak detection method is: use a plug to seal the opening on the lower side of the plastic head of the urea sensor, then use an air gun to inflate the connecting joints on the plastic head of the urea sensor, and then place the plastic head of the sensor in water. After inflation, observe whether bubbles appear in the product in the water. If bubbles are generated, it means that the product is leaking; if no bubbles are generated, it means that the product is not leaking. This method is manual operation with low efficiency, large manual labor, and high misjudgment rate. For this reason, the utility model proposes a fixture and an air tightness detection system for air tightness detection of the plastic head of the urea sensor, in order to improve the air tightness detection efficiency of the plastic head of the urea sensor and reduce the misjudgment rate.

Summary of the invention

The purpose of the utility model is to overcome the defects in the prior art and provide a fixture and an air tightness detection system for the air tightness detection of the plastic head of the urea sensor. When the fixture is used, the air pipe joint at the upper end of the ventilation pipe is connected to an air source with a certain pressure, and the plastic head of the urea sensor to be detected is turned 180 degrees and placed in the storage groove, so that each opening faces upward and each connecting pipe head faces the rear side. The lifting cylinder 1 and the driving cylinder are started by the control system to move the ventilation pipe downward to press the plastic head of the urea sensor longitudinally, and the top rod presses the corresponding connecting pipe head end tightly to seal. At the same time, the plug-in section at the lower end of the ventilation pipe is plugged into the corresponding opening on the plastic head of the urea sensor so that each opening is connected with the corresponding ventilation pipe. The gas is filled into the corresponding openings, internal cavities and air paths of the connecting pipes on the plastic head of the urea sensor in sequence through the vent pipe, and the pressure maintenance of each air path is observed, or the plastic head of the urea sensor to be tested is placed in a water body, and whether bubbles appear in the water body is observed to analyze and judge whether the plastic head of the urea sensor is qualified, thereby realizing the semi-automatic operation of the air tightness detection of the plastic head of the urea sensor, which helps to reduce the workload of manual participation, save labor costs, reduce the rate of manual misjudgment, and improve the detection efficiency at the same time; the control system can also control the action of the driving cylinder one by one to realize the one-by-one detection of the sealing of each connecting pipe on the plastic head of the urea sensor, and the flexibility and applicability are good; the overall structural design is simple, the preparation and implementation feasibility is high, and the practicality is strong. The utility model is a kind of air tightness detection system for the plastic head of the urea sensor, which has a simple structural design and a reasonable layout, and is convenient for realizing the semi-automatic program control of the air tightness detection of the plastic head of the urea sensor, which helps to greatly reduce the workload of manual participation, save labor costs, and improve the detection efficiency at the same time.

One of the purposes of the utility model is to design a fixture for detecting the air tightness of a plastic head of a urea sensor, comprising a base plate, a mounting seat and two guide pillars respectively located on the left and right sides of the mounting seat are fixedly provided on the front side of the upper end of the base plate, the tops of the two guide pillars are fixedly connected by a top plate, a lifting cylinder with a piston rod vertically downward is installed on the top plate, a sliding plate is fixedly provided at the end of the piston rod of the lifting cylinder, one end of the sliding plate is mounted on one guide pillar through a sliding sleeve sliding sleeve, and the other end is mounted on the other guide pillar through a sliding sleeve sliding sleeve, a storage groove for accommodating the plastic head of the urea sensor is provided on the mounting seat, a plurality of vent pipes vertically penetrating the plate body are fixedly provided on the sliding plate, an air pipe joint for connecting an air source pipeline is provided at the upper end of the vent pipe, and a plug-in section adapted to be plugged and matched with an opening on the lower side of the plastic head of the urea sensor is provided at the lower side of the base plate, and a plurality of push rod mechanisms for blocking the end of the connecting pipe head on the plastic head of the urea sensor are provided on the rear side of the base plate.

The utility model discloses a clamp for detecting the air tightness of a plastic head of a urea sensor. When in use, the air pipe joint at the upper end of the vent pipe is externally connected to an air source of a certain pressure, the plastic head of the urea sensor to be detected is turned 180 degrees and then placed inside a storage slot, so that each opening faces upward and each connecting pipe head faces the rear side, and the control system starts a lifting cylinder and a driving cylinder to move the vent pipe downward to press the plastic head of the urea sensor longitudinally, and the top rod presses the corresponding connecting pipe head end tightly to seal, and at the same time, the plug-in section at the lower end of the vent pipe is plugged into the corresponding opening on the plastic head of the urea sensor so that each opening is connected to the corresponding vent pipe, and the gas of a certain pressure is sequentially filled into the urea sensor through the vent pipe. In the corresponding openings, internal cavities and air paths of the connecting pipes on the plastic head of the sensor, the pressure maintenance of each air path is observed, or the plastic head of the urea sensor to be tested is placed in the water body to observe whether bubbles appear in the water body to analyze and judge whether the plastic head of the urea sensor is qualified, thereby realizing the semi-automatic operation of the air tightness detection of the plastic head of the urea sensor, which helps to reduce the workload of manual participation, save labor costs, reduce the rate of manual misjudgment, and improve the detection efficiency at the same time; the control system can also be used to control the action of the driving cylinder one by one to realize the one-by-one detection of the sealing of each connecting pipe on the plastic head of the urea sensor, which has good flexibility and applicability; the overall structural design is simple, the preparation and implementation feasibility is high, and the practicability is strong.

The preferred technical solution is that the outer side of the plug section is provided with a plurality of annular grooves, and a sealing ring is embedded in the annular groove. The outer side of the plug section is sleeved with a sealing ring, which significantly improves the plug-in sealing effect between the outer wall surface of the plug section at the lower end of the vent pipe and the inner wall surface of the opening on the plastic head of the urea sensor, avoids air leakage from the gap between the fitting surfaces of the plug section and the opening, and significantly improves the accuracy of the air tightness detection of each air pipe joint on the plastic head of the urea sensor.

A further preferred technical solution is that a mounting seat 2 is fixedly provided on the rear side of the base plate, and a plurality of push rods capable of reciprocating forward and backward are movably connected on the mounting seat 2, and a plurality of driving cylinders with piston rods facing the rear side are installed on the lower side of the base plate, and a pair of horizontal arms extending to the rear side are fixedly provided at the left and right ends of the mounting seat 2, and a rotating shaft is fixedly provided between the pair of horizontal arms, and a plurality of connecting rods rotatably connected and installed on the rotating shaft are also included, and the push rod, the connecting rod and the driving cylinder correspond to each other, and the lower end of the connecting rod is hinged with the piston rod end of the driving cylinder, and the upper end is provided with a U-shaped groove and a waist-shaped hole penetrating the two side arms of the U-shaped groove, and the rear end of the push rod is provided with a mounting hole, and the rear end of the push rod is inserted into the U-shaped groove and is hingedly connected with the upper end of the connecting rod through a pin shaft penetrating the waist-shaped hole and the mounting hole, and the corresponding push rod, the connecting rod and the driving cylinder constitute the push rod mechanism. The push rod mechanism has a simple structural design, which ensures that the clamp of the utility model can be smoothly prepared and implemented, and at the same time significantly improves the compactness and rationality of the clamp of the utility model.

A further preferred technical solution is that a flexible pad is provided at the front end of the push rod. The flexible pad improves the sealing effect of the push rod end against the ends of the connecting pipes on the plastic head of the urea sensor, and effectively prevents the push rod end from causing hard pressure damage to the ends of the connecting pipes on the plastic head of the urea sensor.

A further preferred technical solution is that a U-shaped frame and a plurality of pads are provided on the lower side of the bottom plate along the left and right directions, and a plurality of driving cylinders are fixed on the U-shaped frame or the pads, so that the driving cylinders can be arranged and installed on the lower side of the bottom plate, which helps to improve the overall compactness and rationality of the clamp of the utility model.

A further preferred technical solution also includes a push rod, one end of which is fixedly connected to the end of the piston rod of the driving cylinder, and the other end is provided with a U-shaped joint with a mounting hole, the lower end of the connecting rod is provided with a mounting hole, the lower end of the connecting rod is inserted into the U-shaped joint of the push rod, and is hingedly connected by a pin shaft passing through the mounting holes on the two.

A further preferred technical solution also includes a circular pad, the mounting seat 1 has arm side plates located at the left and right side edges and a front side plate located at the front side edge, the arm side plates located at the left and right side edges and the front side plate enclose to form a storage groove opening toward the top and the rear, and the height of the front side plate is less than the height of the arm side plate, and a V-shaped pressure block capable of horizontal rotation is installed on the upper end surface of the arm side plate. During detection, the urea sensor plastic head is installed inside the storage groove on the mounting seat 1, and the circular pad is coaxially placed on the outer peripheral edge of the upper side of the urea sensor plastic head, and the V-shaped pressure block is pressed tightly on the upper side of the circular pad. The circular pad can evenly distribute the pressure applied by the V-shaped pressure blocks on both sides on the urea sensor plastic head to avoid local stress concentration causing hard pressure damage to the urea sensor plastic head.

The second purpose of the utility model is to design an air tightness detection system for the plastic head of a urea sensor, including the above-mentioned fixture and frame for air tightness detection of the plastic head of a urea sensor, wherein the frame has a water tank with an upper opening on the front side below, and a support plate on the rear side above the frame, and a lifting cylinder 2 and an L-shaped storage table that can slide up and down are installed on the front side of the support plate, and the L-shaped storage table is fixedly connected to the piston rod end of the lifting cylinder 2, and the vertical plate of the L-shaped storage table is also slidably installed on the front side of the support plate through a slide rail assembly, and the bottom plate of the urea sensor plastic head fixture is fixedly arranged on the upper end surface of the horizontal plate of the L-shaped storage table, and the frame is also provided with a manual start-stop switch located on the outer periphery of the water tank.

The utility model discloses an air tightness detection system for the plastic head of a urea sensor, which has a simple structural design and a reasonable layout, and is convenient for realizing semi-automatic program control of the air tightness detection of the plastic head of the urea sensor, thereby helping to greatly reduce the amount of manual labor involved, save labor costs, and improve detection efficiency.

The preferred technical solution also includes several cameras surrounding the upper edge of the water tank, several air source connecting heads facing the top of the water tank are arranged in the middle of the frame, an air source connected to the inner end of the air source connecting head is arranged inside the frame, a display screen and a touch panel electrically connected to the control system are arranged above the frame, several cameras are connected to the control system, the air source connecting head has a control valve, and the air pipe joint at the upper end of the ventilation pipe is connected to the outer end of the air source connecting head through a pipeline. The detection status during the air tightness detection of the urea sensor plastic head can be fed back to the display screen, which is convenient for the operator to observe and judge whether the product is qualified in time. The inflation pressure and pressure holding time during the detection can also be set through the touch panel, which helps to improve the flexibility and applicability of the air tightness detection system of the utility model.

In order to further improve the air tightness detection efficiency of the urea sensor plastic head, a further preferred technical solution is that at least two sets of the urea sensor plastic head clamps are fixedly provided on the horizontal plate of the L-shaped storage table.

The advantages and beneficial effects of the utility model are:

1. The utility model is a fixture for detecting the air tightness of the plastic head of a urea sensor. When in use, the air pipe joint at the upper end of the vent pipe is connected to an air source of a certain pressure. The plastic head of the urea sensor to be detected is turned 180 degrees and placed inside the storage tank, so that each opening faces upward and each connecting head faces the rear side. The control system starts the lifting cylinder and the driving cylinder to move the vent pipe downward to press the plastic head of the urea sensor longitudinally, and the top rod presses the corresponding connecting head end tightly to seal. At the same time, the plug-in section at the lower end of the vent pipe is plugged into the corresponding opening on the plastic head of the urea sensor so that each opening is connected to the corresponding vent pipe. Gas of a certain pressure is filled into the urea sensor in sequence through the vent pipe. In the corresponding openings, internal cavities and air paths of the connecting pipes on the plastic head of the sensor, the pressure maintenance of each air path is observed, or the plastic head of the urea sensor to be tested is placed in the water body to observe whether bubbles appear in the water body to analyze and judge whether the plastic head of the urea sensor is qualified, thereby realizing the semi-automatic operation of the air tightness detection of the plastic head of the urea sensor, which helps to reduce the workload of manual participation, save labor costs, reduce the rate of manual misjudgment, and improve the detection efficiency at the same time; the control system can also be used to control the action of the driving cylinder one by one to realize the one-by-one detection of the sealing of each connecting pipe on the plastic head of the urea sensor, which has good flexibility and applicability; the overall structural design is simple, the preparation and implementation feasibility is high, and the practicability is strong.

2. The outer side of the plug section is provided with a plurality of annular grooves, and a sealing ring is embedded in the annular groove. The outer side of the plug section is sleeved with a sealing ring, which significantly improves the plug-in sealing effect between the outer wall surface of the plug section at the lower end of the ventilation pipe and the inner wall surface of the opening on the plastic head of the urea sensor, avoids air leakage from the gap between the fitting surfaces of the plug section and the opening, and significantly improves the accuracy of the air tightness detection of each air pipe joint on the plastic head of the urea sensor.

3. A flexible pad is provided at the front end of the push rod. The flexible pad improves the sealing effect of the push rod end against the ends of the connecting pipes on the plastic head of the urea sensor, and effectively prevents the push rod end from causing hard pressure damage to the ends of the connecting pipes on the plastic head of the urea sensor.

4. The circular pad can evenly distribute the pressure applied by the V-shaped pressure blocks on both sides to the plastic head of the urea sensor, avoiding local stress concentration and causing hard pressure damage to the plastic head of the urea sensor.

5. The utility model is an air tightness detection system for the plastic head of a urea sensor, which has a simple structural design and a reasonable layout, and is convenient for realizing semi-automatic program control of the air tightness detection of the plastic head of the urea sensor, which helps to greatly reduce the amount of manual labor involved, save labor costs, and improve detection efficiency.

6. The detection results of the air tightness test of the plastic head of the urea sensor can be fed back to the display screen, which is convenient for the operator to observe and judge whether the product is qualified in time. The inflation pressure and pressure holding time during the test can also be set through the touch panel, which helps to improve the flexibility and applicability of the air tightness detection system of the utility model.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a perspective view of a plastic head of a urea sensor from the left front side in the background art;

FIG2 is a bottom-up perspective view of a plastic head of a urea sensor in the background art;

FIG3 is a top-down perspective view of a fixture for detecting air tightness of a plastic head of a urea sensor in Example 1 from the right front side;

FIG4 is a partial enlarged view of the H in FIG3;

FIG5 is a top left rear perspective view of a fixture for detecting air tightness of a plastic head of a urea sensor in Example 1;

6 is a left rear side upward perspective view of a fixture for air tightness detection of a plastic head of a urea sensor in Example 1;

7 is a front view of a fixture used for air tightness detection of a urea sensor plastic head in Example 1 in use;

8 is a right front side top view of an air tightness detection system for a urea sensor plastic head in Example 2 (the connecting pipe between the air source pipe connector and the air pipe connector is hidden);

FIG. 9 is an assembly diagram of a fixture for testing the air tightness of a urea sensor plastic head on an L-shaped storage table.

In the figure: A, water inlet pipe head; B, water return pipe head; C, urea suction pipe head; D, urea return pipe head; E, ventilation pipe head; F, plastic head body; a, water inlet hole; b, water return hole; c, urea suction hole; d, urea return hole; e, ventilation hole; 1, bottom plate; 2, mounting seat 1; 3, V-shaped pressure block; 4, guide column; 5, top plate; 6, sliding plate; 7, sliding sleeve; 8, lifting cylinder 1; 9, mounting seat 2; 10, ventilation pipe; 11, sealing ring; 12, push rod; 13, connecting rod; 14, driving cylinder; 15, U-shaped frame; 16, cushion block; 17, air pipe joint; 18, push rod; 19, round Pad; 20, rack; 2-1, storage slot; 2-2, front side plate; 2-3, arm side plate; 9-1, horizontal support arm; 9-2, rotating shaft; 10-1, plug-in section; 10-2, annular groove; 12-1, flexible pad; 13-1, U-shaped groove; 13-2, waist-shaped hole; 18-1, U-shaped joint; 20-1, water tank; 20-2, support plate; 20-3, L-shaped storage table; 20-4, slide rail assembly; 20-5, lifting cylinder 2; 20-6, display screen; 20-7, touch panel; 20-8, camera; 20-9, air supply connection head; 20-10, manual start-stop switch.

DETAILED DESCRIPTION

The specific implementation of the utility model is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

Example 1

As shown in Figures 1 to 7, the utility model is a fixture for detecting the air tightness of the plastic head of a urea sensor, comprising a bottom plate 1, a mounting seat 2 and two guide pillars 4 respectively located on the left and right sides of the mounting seat 2 are fixedly provided on the front side of the upper end of the bottom plate 1, the tops of the two guide pillars 4 are fixedly connected by a top plate 5, a lifting cylinder 8 with a piston rod vertically downward is installed on the top plate 5, a sliding plate 6 is fixedly provided at the end of the piston rod of the lifting cylinder 8, and one end of the sliding plate 6 is slidably sleeved and installed on a guide pillar 4 through a sliding sleeve 7 The upper end and the other end are slidably mounted on another guide column 4 through a sliding sleeve 7. The mounting seat 2 is provided with a storage groove 2-1 for accommodating the plastic head of the urea sensor. The sliding plate 6 is fixed with a plurality of ventilation pipes 10 vertically penetrating the plate body. The upper end of the ventilation pipe 10 is provided with an air pipe joint 17 for connecting the air source pipeline, and the lower end is provided with a plug-in section 10-1 that is plugged and adapted to the opening on the lower side of the plastic head of the urea sensor. The rear side of the base plate 1 is provided with a plurality of push rod mechanisms for blocking the end of the pipe head on the plastic head of the urea sensor.

Preferably, the outer side surface of the plug-in section 10 - 1 is provided with a plurality of annular grooves 10 - 2 , and a sealing ring 11 is embedded in the annular groove 10 - 2 .

Further preferably, a mounting seat 29 is fixedly provided on the rear side of the base plate 1, and a plurality of push rods 12 capable of reciprocating forward and backward are movably connected on the mounting seat 29, and a plurality of driving cylinders 14 with piston rods facing the rear side are installed on the lower side of the base plate 1, and a pair of horizontal support arms 9-1 extending to the rear side are fixedly provided at the left and right ends of the mounting seat 29, and a rotating shaft 9-2 is fixedly provided between the pair of horizontal support arms 9-1, and also includes a plurality of connecting rods 13 rotatably connected and installed on the rotating shaft 9-2, and the push rods 12 and the connecting rods 13 and the driving cylinder 14 correspond one to one, the lower end of the connecting rod 13 is hinged with the piston rod end of the driving cylinder 14, the upper end is provided with a U-shaped groove 13-1 and a waist-shaped hole 13-2 passing through the two side arms of the U-shaped groove 13-1, the rear end of the push rod 12 is provided with a mounting hole, the rear end of the push rod (12) is inserted into the U-shaped groove 13-1 and is hingedly connected to the upper end of the connecting rod 13 through a pin shaft passing through the waist-shaped hole 13-2 and the mounting hole, and the corresponding push rod 12, connecting rod 13 and driving cylinder 14 constitute the push rod mechanism.

Further preferably, there are five ventilation pipes 10, and there are five push rods 12, connecting rods 13 and driving cylinders 14 respectively. During detection, the free ends of the five push rods 12 correspond one by one to the water inlet pipe head A, the water return pipe head B, the urea absorption pipe head C, the urea return pipe head D, and the ventilation pipe head E on the plastic head of the urea sensor installed in the storage slot 2-1 on the mounting seat 2, and the plug-in sections 10-1 on the five ventilation pipes 10 correspond one by one to the water inlet hole a, the water return hole b, the urea absorption hole c, the urea return hole d, and the ventilation hole e on the plastic head of the urea sensor installed in the storage slot 2-1 on the mounting seat 2.

Further preferably, a flexible pad 12 - 1 is provided at the front end of the push rod 12 , and the flexible pad 12 - 1 is made of elastin.

Further preferably, a U-shaped frame 15 and a plurality of cushion blocks 16 are provided on the lower side of the base plate 1 along the left-right direction, and the plurality of driving cylinders 14 are fixedly mounted on the U-shaped frame 15 or the cushion blocks 16 .

Further preferably, it also includes a push rod 18, one end of which is fixedly connected to the piston rod end of the driving cylinder 14, and the other end is provided with a U-shaped joint 18-1 with a mounting hole, and the lower end of the connecting rod 13 is provided with a mounting hole, and the lower end of the connecting rod 13 is inserted into the U-shaped joint 18-1 of the push rod 18, and is hingedly connected by a pin shaft passing through the mounting holes on the two.

Further preferably, it also includes a circular pad 19, and the mounting seat 2 has arm side plates 2-3 located on the left and right side edges and a front side plate 2-2 located on the front side edge. The arm side plates 2-3 located on the left and right side edges and the front side plate 2-2 enclose a storage groove 2-1 with an opening facing upward and rearward, and the height of the front side plate 2-2 is less than the height of the arm side plate 2-3. A V-shaped pressure block 3 capable of horizontal rotation is installed on the upper end surface of the arm side plate 2-3. During detection, the plastic head of the urea sensor is installed inside the storage groove 2-1 on the mounting seat 2, and the circular pad 19 is coaxially placed on the outer peripheral edge of the upper side of the plastic head of the urea sensor, and the V-shaped pressure block 3 is pressed tightly on the upper side surface of the circular pad 19.

The utility model discloses a clamp for detecting the air tightness of a plastic head of a urea sensor. When in use, the air pipe joint at the upper end of the vent pipe is externally connected to an air source of a certain pressure, the plastic head of the urea sensor to be detected is turned 180 degrees and then placed inside a storage slot, so that each opening faces upward and each connecting pipe head faces the rear side, and the control system starts a lifting cylinder and a driving cylinder to move the vent pipe downward to press the plastic head of the urea sensor longitudinally, and the top rod presses the corresponding connecting pipe head end tightly to seal, and at the same time, the plug-in section at the lower end of the vent pipe is plugged into the corresponding opening on the plastic head of the urea sensor so that each opening is connected to the corresponding vent pipe, and the gas of a certain pressure is sequentially filled into the urea sensor through the vent pipe. In the corresponding openings, internal cavities and air paths of the connecting pipes on the plastic head of the sensor, observe the pressure maintenance of each air path, or place the plastic head of the urea sensor to be tested in the water body, and observe whether bubbles appear in the water body to analyze and judge whether the plastic head of the urea sensor is qualified, thereby realizing the semi-automatic operation of the air tightness detection of the plastic head of the urea sensor, which helps to reduce the workload of manual participation, save labor costs, reduce the rate of manual misjudgment, and improve the detection efficiency; the control system can also be used to control the action of the driving cylinder one by one to realize the one-by-one detection of the sealing of each connecting pipe on the plastic head of the urea sensor, with good flexibility and applicability; the overall structural design is simple, the preparation and implementation feasibility is high, and the practicability is strong.

Example 2

As shown in Figures 8 and 9, an air tightness detection system for a urea sensor plastic head comprises a fixture and a frame 20 for air tightness detection of a urea sensor plastic head as described in Example 1, wherein the frame 20 has a water tank 20-1 with an upper opening on the front side below, and a support plate 20-2 on the rear side above the frame 20, and a lifting cylinder 20-5 and an L-shaped storage table 20-3 that can slide up and down are installed on the front side of the support plate 20-2, and the L-shaped storage table 20-3 is fixedly connected to the piston rod end of the lifting cylinder 20-5, and the vertical plate of the L-shaped storage table 20-3 is also slidably installed on the front side of the support plate 20-2 through a slide rail assembly 20-4, and the bottom plate 1 of the urea sensor plastic head fixture is fixedly arranged on the upper surface of the horizontal plate of the L-shaped storage table 20-3, and the frame 20 is also provided with a manual start-stop switch 20-10 located on the outer periphery of the water tank 20-1.

Preferably, it also includes a plurality of cameras 20-8 surrounding the upper edge of the water tank 20-1, a plurality of air source connecting heads 20-9 facing the top of the water tank 20-1 are provided in the middle of the frame 20, an air source connected to the inner end of the air source connecting head 20-9 is provided inside the frame 20, a display screen 20-6 and a touch panel 20-7 electrically connected to the control system are provided above the frame 20, a plurality of the cameras 20-8 are connected to the control system, a control valve is provided on the air source connecting head 20-9, and the air pipe joint 17 at the upper end of the ventilation pipe 10 is connected to the outer end of the air source connecting head 20-9 through a pipeline.

Further preferably, at least two sets of the urea sensor plastic head fixtures are fixedly disposed on the horizontal plate of the L-shaped storage platform 20 - 3 .

The utility model is a kind of air tightness detection system for urea sensor plastic head. The use principle is:

(I) Used for overall detection of the air tightness of the connecting head of the urea sensor plastic head: As shown in FIG7 , the urea sensor plastic head to be detected is turned 180° and placed inside the storage tank 2-1, with each connecting head facing the rear side and each opening (water inlet a, water return hole b, urea absorption hole c, urea return hole d, vent hole e) facing upward, and the circular pad 19 is coaxially placed on the outer peripheral edge of the upper side of the urea sensor plastic, and then the V-shaped pressing block 3 on the arm side plate 2-3 is rotated and pressed on the circular pad 19. At this time, the urea sensor plastic head to be detected is pressed and fixed inside the storage tank 2-1; through the touch panel 20 -7 Set the test conditions (such as test inflation pressure, pressure holding time, etc.), start the test start program through the manual start-stop switch 20-10, the piston rods of the five driving cylinders 14 drive the corresponding connecting rods 13 to drive the push rods 12 to move forward, so that the flexible pads 12-1 at the front ends of the five push rods 12 respectively correspond to the corresponding water inlet pipe head A, water return pipe head B, urea suction pipe head C, urea return pipe head D, and ventilation pipe head E on the plastic head of the urea sensor to be tested. At the same time, the piston rod of the lifting cylinder 18 drives the sliding sleeves 7 at both ends of the sliding plate 6 to move downward along the two guide pillars 4. The first step is to move the plug-in sections 10-1 at the lower ends of the five ventilation pipes 10 to be respectively plugged into the corresponding water inlet hole a, water return hole b, urea absorption hole c, urea return hole d, and ventilation hole e on the plastic head of the urea sensor to be detected; then, the piston rod of the lifting cylinder 20-5 begins to extend, so that the L-shaped storage platform 20-3 drives the clamp to move downward, so that the plastic head of the urea sensor to be detected is immersed in the water body of the water tank 20-1 and maintained for a period of time. During this period, the camera 20-8 will display the detection situation in the water tank 20-1 on the display screen 20-6 in real time through the control system, which is convenient for the operator to observe. Determine whether the urea sensor plastic head to be tested is qualified (see Figures 8 and 9); if no bubbles emerge in the water tank 20-1, it means that the urea sensor plastic head is a good product, otherwise it is a defective product. The pressure holding time ends, and the piston rod of the lifting cylinder 20-5 shrinks and resets, so that the L-shaped storage table 20-3 drives the clamp to move upward, and then the five driving cylinders 14 control the five top plates 12 to move backward and separate from the corresponding connecting pipe heads, and the V-shaped pressure blocks 3 on both sides are rotated to separate from the circular pad 19, and the tested urea sensor plastic head is removed, completing a urea sensor plastic head air tightness detection cycle.

(II) The air tightness detection system for the plastic head of the urea sensor of the utility model can also be used to detect the air tightness of the water inlet pipe head A, the water return pipe head B, the urea absorption pipe head C, the urea return pipe head D, and the ventilation pipe head E on the plastic head of the urea sensor one by one. The difference between its operating principle and the air tightness principle for the overall detection of the pipe heads of the urea sensor plastic head is that the driving motor 14 corresponding to the target detection pipe head is controlled by the touch panel 20-7 to drive the corresponding push rod 12 to the pipe head to be detected (inlet pipe head The water pipe joint A, the return water pipe joint B, the urea suction pipe joint C, the urea return pipe joint D, and the ventilation pipe joint E are tightly sealed, and then the piston rod is extended by the lifting cylinder 20-5 to immerse the urea sensor plastic head in the water body of the water tank 20-1, and observe whether there are bubbles in the water body of the water tank 20-1. If there are no bubbles in the water tank 20-1, it means that the sealing of the pipe joint of the urea sensor plastic head is good, otherwise the sealing is poor; and refer to the above operation to perform air tightness detection on the subsequent pipe joints one by one.

The utility model discloses an air tightness detection system for the plastic head of a urea sensor, which has a simple structural design and a reasonable layout, and is convenient for realizing semi-automatic program control of air tightness detection of the plastic head of the urea sensor, which helps to greatly reduce the amount of manual labor involved, save labor costs, and improve detection efficiency.

The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (10)

1. A fixture for detecting the air tightness of a plastic head of a urea sensor, characterized in that it comprises a bottom plate (1), a mounting seat (2) and two guide pillars (4) respectively located on the left and right sides of the mounting seat (2) are fixedly provided on the front side of the upper end of the bottom plate (1), the tops of the two guide pillars (4) are fixedly connected by a top plate (5), a lifting cylinder (8) with a piston rod vertically downward is installed on the top plate (5), a sliding plate (6) is fixedly provided at the end of the piston rod of the lifting cylinder (8), one end of the sliding plate (6) is slidably sleeved and installed on one of the guide pillars (4) through a sliding sleeve (7). ) and the other end is slidably mounted on another guide column (4) through a sliding sleeve (7); the mounting seat (2) is provided with a storage groove (2-1) for accommodating the plastic head of the urea sensor; the sliding plate (6) is fixed with a plurality of ventilation pipes (10) vertically penetrating the plate body; the upper end of the ventilation pipe (10) is provided with an air pipe joint (17) for connecting to an air source pipeline, and the lower end is provided with a plug-in section (10-1) that is plugged and adapted to the opening on the lower side of the plastic head of the urea sensor; the rear side of the bottom plate (1) is provided with a plurality of push rod mechanisms for blocking the end of the pipe head on the plastic head of the urea sensor. 2. The fixture for detecting the air tightness of the plastic head of a urea sensor as described in claim 1 is characterized in that a plurality of annular grooves (10-2) are provided on the outer side of the plug-in section (10-1), and a sealing ring (11) is embedded in the annular groove (10-2). 3. The fixture for detecting the air tightness of the plastic head of the urea sensor as described in claim 2 is characterized in that a second mounting seat (9) is fixedly provided on the rear side of the base plate (1), a plurality of push rods (12) capable of reciprocating forward and backward are movably connected to the second mounting seat (9), a plurality of driving cylinders (14) with piston rods facing the rear side are installed on the lower side of the base plate (1), a pair of horizontal support arms (9-1) extending toward the rear side are fixedly provided at the left and right ends of the second mounting seat (9), a rotating shaft (9-2) is fixedly provided between the pair of horizontal support arms (9-1), and a plurality of connecting rods rotatably connected and installed on the rotating shaft (9-2) are also included. (13), the push rod (12), the connecting rod (13) and the driving cylinder (14) correspond to each other one by one, the lower end of the connecting rod (13) is hinged with the piston rod end of the driving cylinder (14), the upper end is provided with a U-shaped groove (13-1) and a waist-shaped hole (13-2) penetrating the two side arms of the U-shaped groove (13-1), the rear end of the push rod (12) is provided with a mounting hole, the rear end of the push rod (12) is inserted into the U-shaped groove (13-1) and is hingedly connected to the upper end of the connecting rod (13) through a pin shaft penetrating the waist-shaped hole (13-2) and the mounting hole, and the corresponding push rod (12), the connecting rod (13) and the driving cylinder (14) constitute the push rod mechanism. 4. The fixture for detecting the air tightness of the plastic head of a urea sensor as claimed in claim 3, characterized in that a flexible pad (12-1) is provided at the front end of the push rod (12). 5. The fixture for detecting the air tightness of the plastic head of a urea sensor as described in claim 4 is characterized in that a U-shaped frame (15) and a plurality of cushion blocks (16) are provided on the lower side of the base plate (1) along the left and right directions, and a plurality of the driving cylinders (14) are fixed on the U-shaped frame (15) or the cushion blocks (16). 6. The fixture for detecting the air tightness of the plastic head of a urea sensor as described in claim 5 is characterized in that it also includes a push rod (18), one end of the push rod (18) is fixedly connected to the end of the piston rod of the driving cylinder (14), and the other end is provided with a U-shaped joint (18-1) with a mounting hole, and the lower end of the connecting rod (13) is provided with a mounting hole, and the lower end of the connecting rod (13) is inserted into the U-shaped joint (18-1) of the push rod (18), and is hingedly connected by a pin shaft passing through the mounting holes on the two. 7. The fixture for detecting the air tightness of the urea sensor plastic head as described in claim 6 is characterized in that it also includes a circular pad (19), the mounting seat (2) has arm side plates (2-3) located on the left and right side edges and a front side plate (2-2) located on the front side edge, the arm side plates (2-3) located on the left and right side edges and the front side plate (2-2) enclose a storage groove (2-1) with an opening facing upward and rearward, and the height of the front side plate (2-2) is less than the height of the arm side plate (2-3), and a V-shaped pressure block (3) capable of horizontal rotation is installed on the upper end surface of the arm side plate (2-3). During detection, the urea sensor plastic head is installed inside the storage groove (2-1) on the mounting seat (2), and the circular pad (19) is coaxially placed on the outer peripheral edge of the upper side of the urea sensor plastic head, and the V-shaped pressure block (3) is pressed tightly on the upper side surface of the circular pad (19). 8. A system for detecting the air tightness of a plastic head of a urea sensor, characterized in that it comprises the fixture for detecting the air tightness of a plastic head of a urea sensor and a frame (20) as described in claim 7, wherein the frame (20) has a water tank (20-1) with an upper opening on the front side below, and a support plate (20-2) is provided on the rear side above the frame (20), and a lifting cylinder (20-5) and an L-shaped storage table (20-3) capable of sliding up and down are installed on the front side of the support plate (20-2). ), the L-shaped storage platform (20-3) is fixedly connected to the end of the piston rod of the second lifting cylinder (20-5), the vertical plate of the L-shaped storage platform (20-3) is also slidably installed on the front side of the support plate (20-2) through a slide rail assembly (20-4), the bottom plate (1) of the urea sensor plastic head fixture is fixedly arranged on the upper surface of the horizontal plate of the L-shaped storage platform (20-3), and the frame (20) is also provided with a manual start-stop switch (20-10) located on the outer periphery of the water tank (20-1). 9. The air tightness detection system for the plastic head of a urea sensor as described in claim 8 is characterized in that it also includes a plurality of cameras (20-8) surrounding the upper edge of the water tank (20-1), a plurality of air source connecting heads (20-9) facing the upper side of the water tank (20-1) are provided in the middle of the frame (20), an air source connected to the inner end of the air source connecting head (20-9) is provided inside the frame (20), a display screen (20-6) and a touch panel (20-7) electrically connected to the control system are provided above the frame (20), the plurality of cameras (20-8) are connected to the control system, a control valve is provided on the air source connecting head (20-9), and the air pipe joint (17) at the upper end of the ventilation pipe (10) is connected to the outer end of the air source connecting head (20-9) through a pipeline. 10. The air tightness detection system for the urea sensor plastic head according to claim 9, characterized in that at least two sets of the urea sensor plastic head fixtures are fixedly arranged on the horizontal plate of the L-shaped storage table (20-3).