Water-free detection device and water-free detection method

Abstract

The invention provides a water-free detection device and a water-free detection method, and relates to the technical field of detection equipment. Comprising an air inlet pipeline connected with an air source, and a first test pipeline communicated with the air inlet pipeline; wherein the first test pipeline is provided with a speedup tube, the upstream end of the speedup tube is also provided with a first air pressure sensor, and the downstream end of the speedup tube is provided with a second air pressure sensor which is used for detecting air pressure values of the front end and the rear end of the speedup tube respectively; the speedup tube is suitable for amplifying a differential pressure value of a test product at the downstream end of the speedup tube caused by small change of exhaust flow so as to accurately measure an air pressure difference value at the upstream end and the downstream end of the speedup tube. According to the scheme, the accuracy of water-free detection is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of detection equipment, and in particular to a water-free detection device and a water-free detection method. Background Art

[0002] Existing water effect detection technologies for bathroom products (showers, faucets) mainly rely on manual observation after water testing or by testing the water pressure to determine whether there are defects in the water splash or leakage during water discharge. However, these methods have some significant shortcomings: first, the efficiency of product water testing is low, and the automation level of the detection process is not high; second, the product after water testing needs to undergo a subsequent drying process, which is not only time-consuming, but also easy to leave residual water, which may cause residual water to evaporate during product packaging and transportation.

[0003] The water-free testing device for bathroom products (showers, faucets) can not only improve the inspection efficiency and level of bathroom products, but also solve the problem of residual water drying when bathroom products leave the factory. The existing water-free inspection is generally to maintain pressure inside the product, and then calculate the pressure change after a period of time to determine whether there is leakage and other problems. However, in the existing scheme, the stability during pressure maintenance is low, and the measurement accuracy is low. It is difficult to determine whether the water splash defect is caused by a defective product structure. When the pressure caused by the slight change is small, the change in the parameter being tested (differential pressure) is insufficient, resulting in low detection accuracy and resolution. Summary of the invention

[0004] The invention discloses a water-free detection device, aiming to improve the above-mentioned problems.

[0006] The present invention adopts the following scheme:

[0007] A water-free detection device, comprising: an air intake pipeline connected to an air source, and a first test pipeline connected to the air intake pipeline; wherein the first test pipeline is suitable for connecting a test product, and a third air pressure sensor is arranged on the air intake pipeline to detect the air intake pressure at the air source end;

[0008] The first test pipeline is provided with a speed-increasing tube, a first air pressure sensor is provided at the upstream end of the speed-increasing tube, and a second air pressure sensor is provided at the downstream end, so as to detect the air pressure values ​​at the front and rear ends of the speed-increasing tube respectively; the speed-increasing tube is suitable for amplifying the differential pressure value caused by a slight change in the exhaust flow rate of the test product at its downstream end;

[0009] The device further comprises a second test pipeline connected to the air intake pipeline, wherein a second air intake valve is arranged on the second test pipeline, and a differential pressure sensor is arranged at the downstream end of the second air intake valve, and a gas branch connected to the downstream end of the speed increasing tube is arranged at the other end of the differential pressure sensor to detect the pressure difference between the front and rear ends of the speed increasing tube;

[0010] The water-free detection device is configured to be able to switch between air tightness test and water splash test; when performing the water splash test, the values ​​of the first air pressure sensor and the second air pressure sensor at both ends of the speed increasing tube are read and the difference is made to obtain the differential pressure value at both ends of the speed increasing tube, and then the preset standard differential pressure value is subtracted from the obtained differential pressure value to obtain the water splash loss pressure drop of the test product; when the obtained water splash loss pressure drop is a positive value and is greater than the set water splash pressure drop standard, it is judged that the test product has a weak water discharge effect defect; when the tested water splash loss pressure drop is a negative value and is less than the water splash leakage standard, it is judged that the test product has a water discharge effect leakage defect.

[0011] Furthermore, the speed-increasing tube has a fluid channel with a cross-sectional area smaller than that of the first test pipeline, and the cross-sectional area of ​​the fluid channel of the speed-increasing tube is 1 / 2 to 1 / 5 of the cross-sectional area of ​​the fluid channel of the first test pipeline.

[0012] Furthermore, a first air inlet valve is provided at the upstream end of the speed increasing tube, and an air release valve is provided at the downstream end, and the downstream end of the air release valve is suitable for connecting to a product to be tested.

[0013] Furthermore, it also includes a second test pipeline connected to the intake pipeline, a second intake valve is arranged on the second test pipeline, and a differential pressure sensor is arranged at the downstream end of the second intake valve, and the other end of the differential pressure sensor is provided with a gas branch connected to the downstream end of the speed increaser pipe to detect the pressure difference between the front and rear ends of the speed increaser pipe.

[0014] Furthermore, a normally open valve is provided on the gas branch to control the on-off of the gas branch.

[0015] Furthermore, a pressure regulating valve and a switch main valve are provided on the air intake pipeline to adjust and control the gas pressure of the first test pipeline and the second test pipeline.

[0016] Furthermore, the first air pressure sensor and the second air pressure sensor are RS485 digital signal sensors.

[0017] The present invention also provides a detection method of a water-free detection device, using the water-free detection device described above to perform an airtight test or a water splash test; wherein:

[0018] When performing airtightness testing:

[0019] Adjust the pressure regulating valve to the set inflation pressure, open the switch main valve, the first air inlet valve and the second air inlet valve, close the air release valve, and keep the normally open valve open to stabilize the system pressure before deflation; the pressure regulating valve continues to work at the set inflation pressure, and at the same time, open the air release valve to deflate the system. The deflation stabilization time is 2-3 seconds, so that the system enters a stable deflation state; after stabilization, read the differential pressure rate of the differential pressure sensor to determine whether there is leakage in the internal cavity of the test product;

[0020] When performing the splash test:

[0021] Adjust the pressure regulating valve to the set inflation pressure, open the switch main valve, the first air inlet valve, the air vent valve, and close the normally open valve to stabilize the system pressure before deflation; the pressure regulating valve continues to work at the set inflation pressure to deflate the first test pipeline, and the deflation stabilization time is 2-3 seconds to allow the system to enter a stable deflation state; after stabilization, read the values ​​of the first air pressure sensor and the second air pressure sensor at both ends of the speed increaser tube during the deflation test phase, and calculate the differential pressure value, and subtract the preset standard differential pressure value from the calculated differential pressure value to obtain the splash loss pressure drop of the test product; when the tested splash loss pressure drop is a positive value and greater than the set splash pressure drop standard, it is judged that the test product has a weak water output defect; when the tested splash loss pressure drop is a negative value and less than the splash leakage standard, it is judged that the test product has a leakage defect in the water output effect.

[0022] Beneficial effects:

[0023] In this solution, a speed-increasing tube is set on the first test pipeline, the air pressure difference at both ends of the speed-increasing tube is detected, and the deflation monitoring is continuously performed by active deflation. The speed-increasing tube is set to increase the pressure difference at both ends of the speed-increasing tube. Therefore, when there is a problem with the splash of the sanitary ware product being tested at the downstream end of the speed-increasing tube, the air pressure value at the downstream end of the speed-increasing tube will be changed. The deflation speed-increasing technology is used to achieve sonic deflation, increase the local pressure drop during the deflation process, and magnify the difference in splash loss between the test product with splash defects and the preset standard value, thereby improving the accuracy of splash detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a water-free detection device according to an embodiment of the present invention;

[0025] Icons: Intake pipeline 1, pressure regulating valve 2, switch main valve 3, first test pipeline 4, second test pipeline 5, first intake valve 6, second intake valve 7, first air pressure sensor 8, second air pressure sensor 9, third air pressure sensor 10, normally open valve 11, air release valve 12, test product 13, differential pressure sensor 14, speed increasing tube 15. DETAILED DESCRIPTION

[0026] Example 1

[0027] Combination Figure 1 The present embodiment provides a water-free detection device, comprising: an air intake pipeline 1 connected to an air source, and a first test pipeline 4 connected to the air intake pipeline 1; wherein, a speed-increasing tube 15 is provided on the first test pipeline 4, and the speed-increasing tube 15 is suitable for amplifying the pressure difference between its two ends; a first air pressure sensor 8 is provided at the upstream end of the speed-increasing tube 15, and a second air pressure sensor 9 is provided at the downstream end to respectively detect the air pressure values ​​at the front and rear ends of the speed-increasing tube 15; the speed-increasing tube 15 is suitable for amplifying the differential pressure value caused by a slight change in the exhaust flow rate of the test product at its downstream end, so as to accurately measure the air pressure difference between the upstream and downstream ends of the speed-increasing tube.

[0028] The upstream end of the speed increasing tube 15 is provided with a first air inlet valve 6 , and the downstream end is provided with an air release valve 12 . The downstream end of the air release valve 12 is suitable for connecting to a product 13 to be tested.

[0029] It also includes a second test pipeline 5 connected to the intake pipeline 1, and the second test pipeline 5 is provided with a second intake valve 7, and a differential pressure sensor 14 is provided at the downstream end of the second intake valve 7, and the other end of the differential pressure sensor 14 is provided with a gas branch connected to the downstream end of the speed-increasing tube 15 to detect the pressure difference between the front and rear ends of the speed-increasing tube 15, and a normally open valve 11 is provided on the gas branch to control the on-off of the gas branch. The intake pipeline 1 is provided with a pressure regulating valve 2 and a switch main valve 3 to adjust and control the gas pressure of the first test pipeline 4 and the second test pipeline 5. The intake pipeline 1 is provided with a third air pressure sensor 10 to detect the intake pressure at the air source end.

[0030] In this embodiment, the product to be tested 13 can be a bathroom product, such as a shower head, a faucet, etc., and can also be used for air tightness testing and water splash testing of other water-passing products. The air source end of the air inlet pipeline 1 can be connected to an air storage tank. In order to ensure that the system has sufficient stable deflation flow during the pressure stabilization and test deflation stages, a third air pressure sensor 10 is set at the air source end to monitor its pressure. During the deflation stabilization and water splash test stages, if the air source pressure drops below the set charging and deflation pressure, the pressure regulating valve 2 cannot provide the set charging and deflation pressure of the system. The system will stop the test process and alarm to ensure the accuracy of the test.

[0031] The speed-increasing tube 15 has a fluid channel with a cross-sectional area smaller than that of the first test pipeline 4, and the cross-sectional area of ​​the fluid channel of the speed-increasing tube 15 is 1 / 2 to 1 / 5 of the cross-sectional area of ​​the fluid channel of the first test pipeline 4. In this embodiment, the cross-sectional area of ​​the fluid channel in the speed-increasing tube 15 is smaller than the cross-sectional area of ​​the fluid channel of the first test pipeline 4. Since the reduction of the fluid channel area will increase the flow rate of the gas when passing through the speed-increasing tube 15, the cross-sectional area of ​​the fluid channel of the speed-increasing tube 15 is set to 1 / 2 to 1 / 5 of the cross-sectional area of ​​the fluid channel of the first test pipeline 4. Under the preset air pressure, the flow rate of the speed of sound can be reached, and the gas flow at the front and rear ends of the speed-increasing tube 15 remains unchanged. Therefore, when the air pressure in the system is stable, the differential pressure value caused by the slight change in the exhaust flow of the test product 13 will be amplified to the maximum value, which is conducive to improving the test accuracy. Then, the actual measured pressure difference value is compared with the preset standard pressure difference value range to determine whether the test product 13 has a problem. The preset standard pressure difference value here can be obtained by testing a good product, or it can be manually set according to the product standard. For example, the fluctuation range of the differential pressure value during the splash test of a good product is between -10Pa and 10Pa; the splash differential pressure of a weakly defective product is greater than 1000Pa, and the differential pressure of a leaking product is less than -1000Pa. The difference between the preset standard differential pressure value and the differential pressure value detected and obtained by the air pressure sensor is defined as the splash loss pressure drop. When the tested splash loss pressure drop is a positive value and greater than the set splash pressure drop standard, the product is judged to have a weak water output defect; when the tested splash loss pressure drop is a negative value and less than the splash leakage standard, the product is judged to have a leaking water output defect.

[0032] In one embodiment, the first air pressure sensor 8, the second air pressure sensor 9, and the third air pressure sensor 10 all use RS485 model digital signal sensors to improve test accuracy. The digital signal sensor can make the test accuracy reach more than one ten-thousandth, which can improve the accuracy of water splash detection and leakage detection.

[0033] This embodiment scheme compares the differential pressure (i.e., water splash loss) between the test product 13 and the standard good product by means of active deflation and comparative testing, and judges the water discharge effect of the test product 13 by the slight difference in the deflation flow rate between the product and the standard good product. By means of an air storage tank, a large-flow pressure regulating valve 2, and real-time monitoring of the air source pressure, it is ensured that there is sufficient deflation flow and stability during the deflation stabilization and testing stages. The deflation acceleration technology is used to achieve sonic deflation, increase the local pressure drop during the deflation process, and amplify the difference in water splash loss between the test product 13 with a water splash defect and a good product. In combination with a digital signal air pressure sensor, the accuracy of water splash detection can be improved, so that the test accuracy of pressure reading during water splash and leakage testing reaches ±1Pa.

[0034] Example 2

[0035] The present invention also provides a detection method of a water-free detection device, using the water-free detection device to perform an airtight test or a water splash test; wherein:

[0036] When performing airtightness testing:

[0037] The water outlet of the workpiece is sealed by standard tooling, the pressure regulating valve 2 is adjusted to the set inflation pressure, the switch main valve 3, the first air inlet valve 6 and the second air inlet valve 7 are opened, the air release valve 12 is closed, and the normally open valve 11 is kept open to stabilize the pressure of the system before deflation; the pressure regulating valve 2 continues to work at the set inflation pressure, and the air release valve 12 is opened to deflate the system at the same time, and the deflation stabilization time is 2-3 seconds, so that the system enters a stable deflation state; after stabilization, the differential pressure rate of the differential pressure sensor is read to determine whether there is leakage in the internal cavity of the shower head;

[0038] When performing the splash test:

[0039] Adjust the pressure regulating valve 2 to the set inflation pressure, open the switch main valve 3 and the first air inlet valve 6, open the air vent valve 12, and close the normally open valve 11 to stabilize the system pressure before deflation; the pressure regulating valve 2 continues to work at the set inflation pressure to deflate the first test pipeline 4, and the deflation stabilization time is 2-3 seconds to allow the system to enter a stable deflation state; after stabilization, read the values ​​of the first air pressure sensor 8 and the second air pressure sensor 9 at both ends of the speed increasing tube 15 during the deflation test phase, and calculate the differential pressure value, and subtract the preset standard differential pressure value from the calculated differential pressure value to obtain the splash loss pressure drop of the test product 13; when the tested splash loss pressure drop is a positive value and greater than the set splash pressure drop standard, it is judged that the product has a weak water outlet defect; when the tested splash loss pressure drop is a negative value and less than the splash leakage standard, it is judged that the product has a leakage defect.

[0040] In this embodiment, during the air tightness test, the water outlet of the product is first sealed to perform an air tightness test on the inner cavity of the product. During the water splash test, there is no need to seal the water outlet of the product. Before the water splash test on the product to be tested, the standard good workpiece can be tested first. After stabilization by deflation, the pressure difference between the front and rear ends of the speed increasing tube 15 is detected. The standard pressure difference is recorded as the preset standard pressure difference; then the product to be tested is tested, and the preset standard pressure difference is subtracted from the test result, and a judgment is made based on the result. Specifically, when the tested water splash loss pressure drop is a positive value and is greater than the preset water splash pressure drop standard, the product is judged to have a weak water outlet defect (i.e., problems such as blockage, oblique injection or bifurcation occur); when the tested water splash loss pressure drop is a negative value and is less than the water splash leakage standard (this standard is a negative value), the product is judged to have a water outlet defect (and problems such as the water outlet hole becoming larger or leaking significantly).

[0041] This solution can perform air tightness test and water splash test respectively through one system, thereby improving the test function and reducing costs.

[0042] It should be understood that the above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

[0043] The above description of the drawings used in the implementation manner only illustrates certain embodiments of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

Claims

1. A water-free detection device, characterized in that: include: An air intake pipeline connected to an air source, and a first test pipeline connected to the air intake pipeline; wherein the first test pipeline is suitable for connecting a test product, and a third air pressure sensor is provided on the air intake pipeline to detect the air intake pressure at the air source end; The first test pipeline is provided with a speed-increasing tube, a first air pressure sensor is provided at the upstream end of the speed-increasing tube, and a second air pressure sensor is provided at the downstream end, so as to detect the air pressure values ​​at the front and rear ends of the speed-increasing tube respectively; the speed-increasing tube is suitable for amplifying the differential pressure value caused by a slight change in the exhaust flow rate of the test product at its downstream end; The device further comprises a second test pipeline connected to the air intake pipeline, wherein a second air intake valve is arranged on the second test pipeline, and a differential pressure sensor is arranged at the downstream end of the second air intake valve, and a gas branch connected to the downstream end of the speed increasing tube is arranged at the other end of the differential pressure sensor to detect the pressure difference between the front and rear ends of the speed increasing tube; The water-free detection device is configured to be able to switch between air tightness test and water splash test; when performing the water splash test, the values ​​of the first air pressure sensor and the second air pressure sensor at both ends of the speed increasing tube are read and the difference is made to obtain the differential pressure value at both ends of the speed increasing tube, and then the preset standard differential pressure value is subtracted from the obtained differential pressure value to obtain the water splash loss pressure drop of the test product; when the obtained water splash loss pressure drop is a positive value and is greater than the set water splash pressure drop standard, it is judged that the test product has a weak water discharge effect defect; when the tested water splash loss pressure drop is a negative value and is less than the water splash leakage standard, it is judged that the test product has a water discharge effect leakage defect.

2. The water-free detection device according to claim 1, characterized in that: The speed-increasing tube has a fluid channel with a cross-sectional area smaller than that of the first test pipeline, and the cross-sectional area of ​​the fluid channel of the speed-increasing tube is 1 / 2 to 1 / 5 of the cross-sectional area of ​​the fluid channel of the first test pipeline.

3. The water-free detection device according to claim 1, characterized in that: The upstream end of the speed increasing tube is provided with a first air inlet valve, and the downstream end is provided with an air release valve. The downstream end of the air release valve is suitable for connecting with a product to be tested.

4. The water-free detection device according to claim 1, characterized in that: The gas branch is provided with a normally open valve for controlling the on-off of the gas branch.

5. The water-free detection device according to claim 4, characterized in that: The air intake pipeline is provided with a pressure regulating valve and a switch main valve for regulating and controlling the gas pressure of the first test pipeline and the second test pipeline.

6. The water-free detection device according to claim 1, characterized in that: The first air pressure sensor and the second air pressure sensor adopt RS485 digital signal sensors to improve the test accuracy.

7. A detection method for a water-free detection device, characterized in that: The water-free detection device according to claim 5 is used to perform an airtight test or a water splash test, wherein: When performing airtightness test: Adjust the pressure regulating valve to the set inflation pressure, open the switch main valve, the first air inlet valve and the second air inlet valve, close the air release valve, and keep the normally open valve open to stabilize the system pressure before releasing air; The pressure regulating valve continues to work at the set inflation pressure, and at the same time, the vent valve is opened to deflate the system. The deflation stabilization time is 2-3 seconds, so that the system enters a stable deflation state. After stabilization, the differential pressure rate of the differential pressure sensor is read to determine whether there is leakage in the internal cavity of the test product. When performing a splash test: Adjust the pressure regulating valve to the set inflation pressure, open the main switch valve, the first air inlet valve, the air release valve, and close the normally open valve to stabilize the system pressure before deflation; The pressure regulating valve continues to work at the set inflation pressure to deflate the first test pipeline. The deflation stabilization time is 2-3 seconds to allow the system to enter a stable deflation state. After stabilization, the values ​​of the first air pressure sensor and the second air pressure sensor at both ends of the speed increasing tube are read during the deflation test phase, and the differential pressure value is calculated. The preset standard differential pressure value is subtracted from the calculated differential pressure value to obtain the splash loss pressure drop of the test product. When the tested splash loss pressure drop is a positive value and is greater than the set splash pressure drop standard, the test product is judged to have a weak water output defect. When the tested splash loss pressure drop is a negative value and is less than the splash leakage standard, the test product is judged to have a leakage defect.

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