CN112525500B - Comprehensive calibration system for hydraulic harpoon device - Google Patents
Comprehensive calibration system for hydraulic harpoon device Download PDFInfo
- Publication number
- CN112525500B CN112525500B CN202011192345.3A CN202011192345A CN112525500B CN 112525500 B CN112525500 B CN 112525500B CN 202011192345 A CN202011192345 A CN 202011192345A CN 112525500 B CN112525500 B CN 112525500B
- Authority
- CN
- China
- Prior art keywords
- pressurizing cylinder
- pressure
- oil
- fish fork
- valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention belongs to the technical field of aviation design tests and discloses a comprehensive calibration system for a hydraulic fish fork device. The timer is controlled by the force sensor, the time indexes of the folding and the laying down of the fish fork device are accurately recorded, and quantitative assessment is carried out. The controller controls the grating to rotate, and the force sensor monitors the rotating torque of the harpoon device to obtain the rotating and mooring quantitative indexes of the harpoon device. The oil temperature of the environmental box is sensed through the controller, temperature compensation is carried out through the heater or the cooler, the hydraulic system can be tested in a specified temperature state, and the test accuracy is improved.
Description
Technical Field
The invention belongs to the technical field of aviation design tests, and particularly relates to a comprehensive calibration system for a hydraulic harpoon device.
Background
In the existing ship-based helicopters, a fish fork-grid type carrier landing device which takes a hydraulic system as a power source is mostly used for quickly assisting carrier landing and carrier surface mooring of the helicopter. The fish fork device is an important part of a helicopter hydraulic system and is used for realizing stable and quick carrier landing of a carrier-based helicopter.
In order to ensure that the harpoon device can work safely, reliably and stably after being installed, a test platform is required to be used for checking the properties of the harpoon device, such as retraction time, grating mooring, free rotation and the like before installation. Generally, a test platform of the fish fork device only provides pressure required by retraction and release through a hydraulic system, the retraction and release time cannot be accurately considered due to the short retraction and release time requirement of the fish fork device, the grating mooring performance and the free rotation performance are tested in a manual operation mode, and the obtained assessment indexes are not quantized and accurate enough.
Disclosure of Invention
The invention aims to provide a comprehensive performance calibration device of a hydraulic harpoon device of a ship-borne helicopter, which aims to solve the problems in the prior art that:
(1) Because the requirement on the retraction time of the fish fork device is short, the retraction time of the traditional fish fork calibration device cannot be accurately considered, the retraction time index of the fish fork device can be accurately recorded by controlling the timer through the force sensor, and the problem that the traditional hydraulic fish fork calibration device cannot be quantized is solved;
(2) The check device has the advantages that the check indexes and the test results of the fish spear device are greatly influenced by the temperature of the hydraulic oil liquid, and the measurement and the control of the temperature of the hydraulic oil liquid in the test process are particularly important. According to the hydraulic fish fork calibration device, the temperature of oil in the environmental box is sensed through the controller, and temperature compensation is performed through the heater or the cooler, so that the hydraulic system can be tested in a specified temperature state, and the problem that the test data of the traditional hydraulic fish fork calibration device is inaccurate is solved.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a hydraulic harpoon device comprehensive verification system comprises: the device comprises a fish fork device, a grating, an oil tank, an electric hydraulic pump, a three-position four-way electromagnetic valve, a first pressurizing cylinder, a second pressurizing cylinder, a torque sensor, a microswitch, a timer and a controller;
the input end of the electric hydraulic pump is connected with the oil tank, and the output end of the electric hydraulic pump is connected with a port P of the three-position four-way electromagnetic valve;
the O port of the three-position four-way electromagnetic valve is connected with an oil tank through an oil return pipeline;
the port A of the three-position four-way electromagnetic valve is connected with a rodless cavity of a first pressurizing cylinder;
the port B of the three-position four-way electromagnetic valve is connected with a rod cavity of a first pressurizing cylinder;
the first pressurizing cylinder piston rod is rigidly connected with the second pressurizing cylinder piston rod;
the force sensor is arranged between the first pressurizing cylinder piston rod and the second pressurizing cylinder piston rod and used for monitoring that the first pressurizing cylinder piston rod applies pressure to the second pressurizing cylinder piston rod, and the timer starts to time;
the rodless cavity of the second pressurizing cylinder is connected with the rodless cavity of the fish fork device;
the rod cavity of the second pressurizing cylinder is connected with the rod cavity of the fish fork device;
the fish fork device is arranged above the grating;
the torque sensor is arranged on a rotating shaft of the fish fork device to measure the torque of the fish fork device in the rotating process;
the microswitch is arranged on the fish fork device and used for sending a control signal to stop the timer after monitoring that the fish fork device is locked;
the timer is electrically connected with the micro switch and the force sensor through the controller.
Further, the apparatus further comprises: oil suction oil filter, one-way valve and pressure oil filter;
the oil suction filter is arranged at the input end of the electric hydraulic pump;
the pressure oil filter is arranged between the output end of the electric hydraulic pump and a port P of the three-position four-way electromagnetic valve;
the oil inlet of the one-way valve is connected with the output end of the electric hydraulic pump, and the oil outlet of the one-way valve is connected with the pressure oil filter input end.
Further, the apparatus further comprises: the pressure gauge is connected with a port P of the three-position four-way electromagnetic valve; the pressure gauge is used for monitoring the oil pressure of the P port of the three-position four-way electromagnetic valve in real time.
Further, the apparatus further comprises: a safety valve; the input end of the safety valve is connected with a port P of the three-position four-way electromagnetic valve, and the output end of the safety valve is connected with the oil tank.
Further, the apparatus further comprises: the pressure accumulator, the inflation valve and the barometer;
the hydraulic cavity of the pressure accumulator is connected with a port P of the three-position four-way electromagnetic valve; the pressure chamber of the pressure accumulator is connected with the inflation valve;
the air pressure meter is connected with the air pressure cavity of the pressure accumulator and used for monitoring the pressure of the air pressure cavity.
Further, the apparatus further comprises: two one-way throttle valves; the two one-way throttle valves are respectively arranged between the port A of the three-position four-way electromagnetic valve and the rodless cavity of the first pressurizing cylinder and between the port B of the three-position four-way electromagnetic valve and the rod cavity of the first pressurizing cylinder.
Further, the apparatus further comprises: two self-sealing valves;
and the two self-sealing valves are respectively connected with the rod cavity and the rodless cavity of the second pressurizing cylinder.
Further, the apparatus further comprises: an environmental chamber;
the environment box comprises two pipelines, and each pipeline is connected with a heater, a cooler and a temperature sensor; a pipeline in the environment box connects the rodless cavity of the second pressurizing cylinder with the rodless cavity of the fish fork device; the other pipeline in the environment box connects the rod cavity of the second pressurizing cylinder with the rod cavity of the fish fork device; and the environment box is used for monitoring the oil temperature in the two pipelines and performing temperature compensation through a heater or a cooler.
The invention has the beneficial effects
(1) The timer is controlled by the force sensor, the time indexes of the folding and the laying down of the fish fork device are accurately recorded, and quantitative assessment is carried out.
(2) The controller controls the grating to rotate, and the torque sensor monitors the rotating torque of the harpoon device to obtain the rotating and mooring quantitative indexes of the harpoon device.
(3) The oil temperature of the environmental box is sensed through the controller, temperature compensation is carried out through the heater or the cooler, the hydraulic system can be tested in a specified temperature state, and the test accuracy is improved.
(4) The pressure oil circuit is provided with the pressure accumulator, so that the impact and pressure pulsation of opening and closing of the check valve are effectively reduced.
(5) The oil return path is provided with a safety valve, so that the over-high pressure of the system can be prevented. The system is provided with a flowmeter and a thermometer, can monitor the flow change and the temperature change of the system, and can accurately control the test state.
Drawings
FIG. 1 is a schematic diagram of a comprehensive calibration system for a hydraulic harpoon device;
1-a fish fork device, 2-a grid, 3-an oil tank, 4-an oil suction oil filter, 5-an electric hydraulic pump, 6-a one-way valve, 7-a pressure oil filter, 8-an accumulator, 9-an inflation valve, 10-a barometer, 11-a manometer, 12-a flowmeter, 13-a three-position four-way electromagnetic valve, 14-a one-way throttle valve, 15-a pressurizing cylinder, 16-a force sensor, 17-a pressurizing cylinder, 18-a self-sealing valve, 19-a hose, 20-an environment box, 21-a torque sensor and 22-a microswitch.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings and the detailed description.
As shown in fig. 1, the comprehensive calibration system for the hydraulic fish-fork device comprises a fish-fork device 1, a grating 2, an oil tank 3, an oil suction filter 4, an electric hydraulic pump 5, a one-way valve 6, a pressure oil filter 7, a pressure accumulator 8, an inflation valve 9, a gas pressure gauge 10, a pressure gauge 11, a flow meter 12, a three-position four-way solenoid valve 13, a one-way throttle valve 14, a pressure cylinder 15, a force sensor 16, a pressure cylinder 17, a self-sealing valve 18, a hose 19, an environment box 20, a torque sensor 21 and a microswitch 22.
The oil suction filter 4 is connected with the oil tank 3 and the electric hydraulic pump 5; the electric hydraulic pump 5 is connected with the one-way valve 6, the oil suction filter 4 and the controller; the one-way valve 6 is connected with the electric hydraulic pump 5 and the pressure oil filter 7; the pressure accumulator 8 is connected with the pressure oil filter 7, the inflation valve 9, the barometer 10, the pressure gauge 11 and the flowmeter 12; the three-position four-way electromagnetic valve 13 is connected with the one-way throttle valve 14, the flowmeter 12, the overflow valve and the controller; the pressurizing cylinder 15 is connected with the one-way throttle valve 14, the pressure gauge 11 and the force sensor 16; the pressurizing cylinder 17 is connected with the self-sealing valve 18 and the force sensor 16; the environment box 20 is connected with the hose 19, the upper cavity and the lower cavity of the fish fork device 1 and the controller; wherein a torque sensor 21 is arranged on a rotating shaft of the fish fork device, and the environment box comprises two groups of heaters, coolers and one-way valves; the controller is connected with the microswitch 22, the grille 2, the environment box 20, the force sensor 16, the three-position four-way electromagnetic valve 13, the electric hydraulic pump 5 and the fish fork retracting button; the oil return path is provided with an overflow valve, a flowmeter and a thermometer and is connected with the oil tank 3.
The fish fork device testing device is provided with a power source by the electric hydraulic pump 5, the electric hydraulic pump 5 is filtered 4 through oil absorption oil and is absorbed oil from the hydraulic oil tank 3, pressure oil is filtered 7 through the check valve 6 and the pressure oil, and pressure is supplied to the pressure accumulator 8 and the three-position four-way electromagnetic valve 13. When a fish fork retracting button is pressed, the three-position four-way electromagnetic valve 13 is electrified and switched, so that pressure oil passes through the one-way throttle valve 14 and the pressure gauge 11 and then acts on the pressurizing cylinder 15, the force sensor 16 and the pressurizing cylinder 17, at the moment, the fish fork device is retracted and put down, the force sensor 16 can control the timer, and the retracting and putting down time index of the fish fork device is accurately recorded. The controller senses the position state of the integrated microswitch 22 of the fish fork device and controls the work of the electric hydraulic pump 5 and the work state of the three-position four-way electromagnetic valve 13.
The controller senses the force change of the force sensor 16 to control the timer to enable the grating 2 to rotate, and monitors the rotating torque of the fish fork device through the torque sensor 21 to obtain the rotating and mooring quantitative indexes of the fish fork device. The environment box 20 comprises two groups of heaters, coolers and temperature sensors, the temperature of oil in the environment box is sensed through the controller, temperature compensation is carried out through the heaters or the coolers, a hydraulic system can be tested in a specified temperature state, and the test accuracy is improved. The oil return path is provided with an overflow valve, so that the overhigh pressure of the system can be prevented. The system is provided with a flowmeter and a thermometer, can monitor the flow change and the temperature change of the system, and can accurately control the test state. The oil suction filter 4 and the pressure oil filter 7 are used for cleaning oil in a hydraulic system. An accumulator 8 is arranged in the system for reducing pressure shocks and pressure pulsations in the system.
According to the working principle, an electric hydraulic pump provides a power source for the fish fork device test system, the electric hydraulic pump absorbs oil from a hydraulic oil tank 3 through an oil absorption oil filter 4, pressure oil passes through a one-way valve 6 and a pressure oil filter 7, and pressure is supplied to a pressure accumulator 8 three-position four-way electromagnetic valve 13; the pressure accumulator 8 is arranged in the system and is connected with an inflation valve 9, a gas pressure gauge 10, a pressure gauge 11 and a flow meter 12 for reducing pressure impact and pressure pulsation of the system. The three-position four-way electromagnetic valve 13 is switched to enable pressure oil to pass through the one-way throttle valve 14 and the pressure gauge 11 and then act on the pressurizing cylinder 15 and the force sensor 16, and the sensor 16 can control a timer and accurately record the time index of retracting and putting down of the fish fork device; the pressurizing cylinder 17 is connected with the environment box 20 through a self-sealing valve 18 and a hose 19 and then is connected with the upper cavity and the lower cavity of the fish fork device 1; wherein, a torque sensor 21 is arranged on the rotating shaft of the fish fork device and is used for monitoring the torque change of the fish fork device in the rotating process; the environment box 20 comprises two groups of heaters, coolers and one-way valves, the temperature of oil in the environment box is sensed through the controller, and temperature compensation is performed through the heaters or the coolers, so that a hydraulic system can perform a test in a specified temperature state, and the test accuracy is improved; the controller senses the position state of an integrated microswitch 22 of the fish fork device, controls the work of the electric pump 5 and the work state of the three-position four-way electromagnetic valve 13 by combining with a retractable button of the fish fork device, senses the temperature of oil in the environment box 20 to control a heater and a cooler, senses the force change of the force sensor 16 to control a timer and can control the rotation of the grating 2, and judges the rotation and mooring indexes of the fish fork device through the torque sensor 21; the oil return path is provided with an overflow valve, so that the over-high pressure of the system can be prevented; the system is provided with a flowmeter and a thermometer, can monitor the flow change and the temperature change of the system, and can accurately control the test state. The oil suction filter 4 and the pressure oil filter 7 are used for cleaning oil in a hydraulic system.
When the three-position four-way valve is in the right position, the piston cylinder of the first pressurizing cylinder extends leftwards, the force of the first pressurizing cylinder is transmitted to the second pressurizing cylinder, the piston rod of the second pressurizing cylinder is pushed to move leftwards, and therefore the rodless cavity of the second pressurizing cylinder generates hydraulic pressure to drive the fish fork to move downwards; when the three-position four-way valve is in the left position, the piston cylinder of the first pressurizing cylinder retracts rightwards, the force of the first pressurizing cylinder is transmitted to the second pressurizing cylinder, the piston rod of the second pressurizing cylinder is pulled to move rightwards, and therefore the rod cavity of the second pressurizing cylinder generates hydraulic pressure to drive the fish fork to move upwards.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. The utility model provides a hydraulic pressure harpoon device synthesizes check-up system which characterized in that: the system comprises: the device comprises a fish fork device, a grating, an oil tank, an electric hydraulic pump, a three-position four-way electromagnetic valve, a first pressurizing cylinder, a second pressurizing cylinder, a torque sensor, a force sensor, a microswitch, a timer, a controller and an environment box;
the input end of the electric hydraulic pump is connected with an oil tank, and the output end of the electric hydraulic pump is connected with a port P of the three-position four-way electromagnetic valve;
the O port of the three-position four-way electromagnetic valve is connected with an oil tank through an oil return pipeline;
the port A of the three-position four-way electromagnetic valve is connected with a rodless cavity of a first pressurizing cylinder;
the port B of the three-position four-way electromagnetic valve is connected with a rod cavity of a first pressurizing cylinder;
the first pressurizing cylinder piston rod is rigidly connected with the second pressurizing cylinder piston rod;
the force sensor is arranged between the first pressurizing cylinder piston rod and the second pressurizing cylinder piston rod and used for monitoring that the first pressurizing cylinder piston rod applies pressure to the second pressurizing cylinder piston rod, and the timer starts to time;
the rodless cavity of the second pressurizing cylinder is connected with the rodless cavity of the fish fork device;
the rod cavity of the second pressurizing cylinder is connected with the rod cavity of the fish fork device;
the fish fork device is arranged above the grating;
the torque sensor is arranged on a rotating shaft of the fish fork device to measure the torque of the fish fork device in the rotating process;
the microswitch is arranged on the fish fork device and used for sending a control signal to stop the timer after monitoring that the fish fork device is locked;
the timer is electrically connected with the microswitch and the torque sensor through the controller;
the environment box comprises two pipelines, and each pipeline is connected with a heater, a cooler and a temperature sensor; a pipeline in the environment box connects the rodless cavity of the second pressurizing cylinder with the rodless cavity of the fish fork device; the other pipeline in the environment box connects the rod cavity of the second pressurizing cylinder with the rod cavity of the fish fork device; the environment box is used for monitoring the temperature of oil in the two pipelines and carrying out temperature compensation through a heater or a cooler;
the timer is controlled through the force sensor, the time indexes of the folding and laying down of the fish fork device are accurately recorded, and quantitative assessment is carried out;
the controller controls the grating to rotate, and the torque sensor monitors the rotating torque of the harpoon device to obtain the rotating and mooring quantitative indexes of the harpoon device;
the oil temperature of the environmental box is sensed through the controller, temperature compensation is carried out through the heater or the cooler, the hydraulic system can be tested in a specified temperature state, and the test accuracy is improved.
2. The hydraulic harpoon device comprehensive verification system according to claim 1, characterized in that: the system further comprises: oil suction oil filter, one-way valve and pressure oil filter;
the oil suction filter is arranged at the input end of the electric hydraulic pump;
the pressure oil filter is arranged between the output end of the electric hydraulic pump and a port P of the three-position four-way electromagnetic valve;
the oil inlet of the one-way valve is connected with the output end of the electric hydraulic pump, and the oil outlet of the one-way valve is connected with the pressure oil filter input end.
3. The hydraulic harpoon device comprehensive verification system according to claim 2, characterized in that: the system further comprises: the pressure gauge is connected with a port P of the three-position four-way electromagnetic valve; the pressure gauge is used for monitoring the oil pressure of the P port of the three-position four-way electromagnetic valve in real time.
4. The hydraulic harpoon device comprehensive verification system according to claim 3, characterized in that: the system further comprises: a safety valve; the input end of the safety valve is connected with a P port of the three-position four-way electromagnetic valve, and the output end of the safety valve is connected with the oil tank.
5. The hydraulic harpoon device comprehensive verification system according to claim 4, characterized in that: the system further comprises: the pressure accumulator, the inflation valve and the barometer;
the hydraulic cavity of the pressure accumulator is connected with a port P of the three-position four-way electromagnetic valve; the pressure chamber of the pressure accumulator is connected with the inflation valve;
the air pressure meter is connected with the air pressure cavity of the pressure accumulator and used for monitoring the pressure of the air pressure cavity.
6. The hydraulic harpoon device comprehensive verification system according to claim 1, characterized in that: the system further comprises: two one-way throttle valves; the two one-way throttle valves are respectively arranged between the port A of the three-position four-way electromagnetic valve and the rodless cavity of the first pressurizing cylinder and between the port B of the three-position four-way electromagnetic valve and the rod cavity of the first pressurizing cylinder.
7. The hydraulic harpoon device comprehensive verification system according to claim 1, characterized in that: the system further comprises: two self-sealing valves;
one of the self-sealing valves is arranged between the rod cavity of the second pressurizing cylinder and the rod cavity of the fish fork device;
the other self-sealing valve is arranged between the rodless cavity of the second pressurizing cylinder and the rodless cavity of the fish fork device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011192345.3A CN112525500B (en) | 2020-10-30 | 2020-10-30 | Comprehensive calibration system for hydraulic harpoon device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011192345.3A CN112525500B (en) | 2020-10-30 | 2020-10-30 | Comprehensive calibration system for hydraulic harpoon device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112525500A CN112525500A (en) | 2021-03-19 |
| CN112525500B true CN112525500B (en) | 2023-03-24 |
Family
ID=74979292
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011192345.3A Active CN112525500B (en) | 2020-10-30 | 2020-10-30 | Comprehensive calibration system for hydraulic harpoon device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112525500B (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2943990B1 (en) * | 2009-04-03 | 2011-04-01 | Dcns | ANCHORING HARPO, IN PARTICULAR AN AIRCRAFT AND ANCHORING SYSTEM COMPRISING SUCH A HARPOON. |
| CN109540485B (en) * | 2018-11-12 | 2020-12-25 | 中国直升机设计研究所 | Helicopter ground harpoon control system |
| CN109398735B (en) * | 2018-11-29 | 2020-07-31 | 中国船舶工业系统工程研究院 | Safe and rapid recovery and flying system and method for helicopter in offshore operation |
-
2020
- 2020-10-30 CN CN202011192345.3A patent/CN112525500B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112525500A (en) | 2021-03-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102818676B (en) | Thrust rack in-situ calibration system | |
| CN208443568U (en) | A kind of multifunctional pulse multi-function test stand | |
| CN104569652A (en) | Gas fixed-value checking table for simulating heavy gas fault realization of transformer and checking method | |
| CN106200668A (en) | Outer loop energy resource system and test method thereof for semi-physical simulation | |
| CN109441911B (en) | Hydraulic oil leakage simulation test bed for aircraft pipeline | |
| CN105181355A (en) | Multifunctional testing device of air brake system of tractor transportation unit | |
| CN104236835A (en) | Hydraulic pulse type sealing-detecting vibration test table | |
| CN105298989B (en) | Fault simulation hydraulic control system for electro-hydraulic servo system | |
| CN112525500B (en) | Comprehensive calibration system for hydraulic harpoon device | |
| CN111075780A (en) | Aircraft fuel pipeline pressure pulsation system and working method thereof | |
| CN208313722U (en) | A kind of U heat exchange pressure testing device | |
| CN108730266A (en) | Discharge measuring device and method in a kind of hydraulic cylinder | |
| CN111350721A (en) | Testing arrangement of velocity of propagation of pressure wave in fluid | |
| CN205038026U (en) | Sealed integrality of EMUs carbon slide air flue and continuity test device that flows | |
| CN114486068B (en) | Pressure sensor performance parameter verification testing device | |
| CN212448160U (en) | Aircraft engine lubricating oil pressure gauge equipment | |
| CN108918131B (en) | Testing device for valve under severe working condition | |
| CN108760271A (en) | A kind of the safety valve engaging pressure test device and method of simulation actual condition | |
| CN207180940U (en) | Lubricating oil pressure calibration equipment | |
| CN211693066U (en) | High-precision detection test bed for internal leakage of hydraulic cylinder | |
| CN111237291B (en) | Performance test stand for phosphate oil hydraulic oil tank | |
| CN207728648U (en) | A kind of integrated hydraulic power unit of high pressure high cleanliness two | |
| CN105402204A (en) | Low-temperature test bench for aircraft hydraulic accessory | |
| CN203629805U (en) | Simulated testing device for pressure switch of marine low-speed diesel engine | |
| CN203731083U (en) | Valve detecting device for liquefied natural gas cylinder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |