Oilless vacuum pump shutdown protection system

Abstract

The oil-free vacuum pump shutdown protection system comprises a control unit, a main machine (1) and a driving unit (2), the main machine (1) comprises an air inlet (3) and an air outlet (4), the control unit is electrically connected with the driving unit (2), the control unit is used for controlling the driving unit (2) to work, the driving unit (2) is used for driving the main machine (1) to work, and a water vapor detection unit (5) is arranged at the air outlet (4). The water vapor detection unit (5) is electrically connected with the control unit, the water vapor detection unit (5) is used for providing a water vapor detection signal for the control unit, and the water vapor detection signal is used for the control unit to judge whether the driving unit (2) is shut down or not when a shutdown program is started; the water vapor in the working cavity of the host can be timely discharged during shutdown, so that the use durability and stability of the host can be greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum pumps, in particular to an oil-free vacuum pump shutdown protection system. Background Art

[0002] Since the vacuum pump compression chamber is oil-free and has no cooling lubricant, the cooling of conventional oil-free cooling vacuum pumps mainly relies on low-temperature gas entering the vacuum pump to take away heat. As the vacuum degree increases, the gas that can be extracted also decreases, so the vacuum pump has less air intake and less heat taken away, resulting in high temperature. The high-temperature expansion of the vacuum pump components may eventually cause scraping of the cylinder or seizure, which is prone to failure.

[0003] At present, there is a proposal to use water spray cooling for cooling. In this solution, during the continuous operation of the oil-free vacuum pump, since the main engine of the oil-free vacuum pump is in a relatively high temperature state and continuously generates heat due to operation, it is not easy to generate water accumulation in the main engine working chamber (i.e., the pump chamber). When the oil-free vacuum pump is shut down, the applicant has noticed that the water cannot be drained in time, resulting in water stains in the main engine working chamber, which poses a risk of corroding the metal coating on the inner surface of the main engine working chamber. Therefore, it is particularly important to ensure that the water vapor in the main engine working chamber is drained in time when the pump is shut down. If this can be done, the durability and stability of the main engine can be greatly improved. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the defects of the prior art and propose an oil-free vacuum pump shutdown protection system, which is beneficial to ensure that the water vapor in the main engine working chamber is discharged in time when the main engine is shut down, thereby greatly improving the durability and stability of the main engine.

[0005] Compared with the prior art, the utility model proposes an oil-free vacuum pump shutdown protection system, including a control unit, a main unit and a drive unit. The main unit includes an air inlet and an exhaust port. The control unit is electrically connected to the drive unit. The control unit is used to control the operation of the drive unit. The operation of the drive unit is used to drive the main unit to work. A water vapor detection unit is provided at the exhaust port. The water vapor detection unit is electrically connected to the control unit. The water vapor detection unit is used to provide a water vapor detection signal to the control unit. The water vapor detection signal is used for the control unit to determine whether to shut down the drive unit when starting the shutdown program.

[0006] After adopting the above structure, compared with the prior art, the utility model has the following advantages:

[0007] In the present disclosure, since a water vapor detection unit is provided at the exhaust port, the water vapor detection unit is electrically connected to the control unit, and the water vapor detection signal is provided to the control unit to determine whether to shut down the drive unit when starting the shutdown procedure. Therefore, when the control unit starts the shutdown procedure (for example, the user presses the shutdown switch, the control unit receives the shutdown signal, and gradually reduces the power supply according to the working characteristics of the drive unit (for example, the electric motor) until the power is completely cut off, or the power is cut off immediately. When the power is immediately cut off, due to inertia, the drive unit will continue to rotate for a while before completely stopping), if the water vapor detection signal still shows water vapor, the drive unit will continue to run until the water vapor detected by the water vapor detection signal is lower than the set water vapor threshold, and then the drive unit will be shut down. That is to say, when the user presses the shutdown button, the main unit does not shut down directly, but continues to run, and detects the water content at the exhaust port. After meeting the standard, the main unit is completely shut down.

[0008] Therefore, the present disclosure is helpful to ensure that the water vapor in the working chamber of the main engine is discharged in time when the main engine is shut down, thereby greatly improving the durability and stability of the main engine.

[0009] As an improvement, the main engine is provided with a water spray hole or a spray hole, and the fluid in the water spray hole or the spray hole is controlled to be on and off by a first valve. The first valve is electrically connected to the control unit, and the control unit cuts off the supply of fluid from the water spray hole or the spray hole to the working chamber of the main engine when the shutdown program is started.

[0010] As an improvement, it also includes a temperature detection unit, which is used to detect the temperature of the machine body and / or the exhaust temperature. The temperature detection signal of the temperature detection unit is used by the control unit to determine whether the temperature threshold is exceeded when the shutdown program is started. If the temperature threshold is exceeded, the drive unit is immediately shut down.

[0011] As an improvement, the air inlet of the main unit is provided with a spray hole.

[0012] As an improvement, it also includes a spray rod, which is provided with a plurality of spray holes in sequence along the rod body, the spray rod extends into and is connected to the machine body, the spray rod is arranged on the air intake port, and the spray holes face the air intake port.

[0013] As an improvement, the spray rod can be rotatably arranged to adjust the direction of the water mist.

[0014] As an improvement, the exhaust port is connected to an exhaust pipe, and the water vapor detection unit is located in the exhaust pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the front view of an oil-free vacuum pump shutdown protection system.

[0016] Figure 2 This is an AA section view (exhaust pipe not shown).

[0017] Figure 3The figure is a schematic block diagram of the electrical structure of an oil-free vacuum pump shutdown protection system.

[0018] Explanation of the reference numerals: 1. Main unit, 2. Driving unit, 3. Air inlet, 4. Exhaust port, 5. Water vapor detection unit, 6. Spray hole, 7. Temperature detection unit, 8. Spray rod, 9. Exhaust pipe, 10. Male rotor, 11. Female rotor, 12. Working chamber. DETAILED DESCRIPTION

[0019] The following description is used to disclose the utility model so that those skilled in the art can implement the utility model. The embodiments described below are for example only, and those skilled in the art may think of other obvious variations. The basic principles of the utility model defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the utility model.

[0020] The utility model is further described in detail below:

[0021] For the convenience of description and understanding, the directional description is used for illustration only and does not constitute a limitation on the scope of protection of rights.

[0022] Water is just a synonym. Any suitable cooling liquid is applicable to the present disclosure. Of course, pure water that has been filtered is more suitable for the present disclosure in terms of reducing costs.

[0023] like Figures 1 to 3 As shown, the present disclosure proposes an oil-free vacuum pump shutdown protection system, including a control unit, a main unit 1 and a drive unit 2, the main unit 1 includes an air inlet 3 and an exhaust port 4, the control unit is electrically connected to the drive unit 2, the control unit is used to control the operation of the drive unit 2, the operation of the drive unit 2 is used to drive the main unit 1 to work, a water vapor detection unit 5 is provided at the exhaust port 4, the water vapor detection unit 5 is electrically connected to the control unit, the water vapor detection unit 5 is used to provide a water vapor detection signal to the control unit, and the water vapor detection signal is used for the control unit to determine whether to shut down the drive unit 2 when starting the shutdown program.

[0024] In some embodiments, Figure 2 , 3 As shown, the host 1 is provided with a water spray hole or a spray hole 6, and the fluid in the water spray hole or the spray hole 6 is controlled by a first valve. The first valve is electrically connected to the control unit, and the control unit cuts off the water spray hole or the spray hole 6 from supplying fluid to the working chamber 12 of the host 1 when the shutdown program is started. In this way, no new fluid will enter through the water spray hole or the spray hole 6 during the shutdown process, which is conducive to fully discharging water vapor during the shutdown process.

[0025] In some embodiments, the spray hole 6 is connected to the flow channel between the water source, and a first valve is provided in the spray hole 6 and / or the flow channel. The first valve is electrically connected to the control unit, and the control unit controls the spray hole 6 to start spraying, which means that the control unit controls the first valve to open so that the spray hole 6 sprays. That is: the first case is that the first valve is provided in the spray hole 6, and there is pressurized water in the flow channel. The control unit controls the spray hole 6 to start spraying, which means that the control unit controls the first valve to open so that the spray hole 6 sprays; the second case is that the first valve is provided in the flow channel, and there is pressurized water in the flow channel. The control unit controls the spray hole 6 to start spraying, which means that the control unit controls the first valve to open so that the spray hole 6 sprays; the third case is that the first valve is provided in both the spray hole 6 and the flow channel, and each first valve is opened to allow the spray hole 6 to spray. The aforementioned scheme requires water to maintain a certain pressure in the flow channel, and when spraying is required, the first valve can be opened. Of course, the above scheme is only an example, and any feasible scheme for controlling the on and off of the spray hole 6 can be applied to the present disclosure. For example, the spray hole 6 is provided with a one-way valve, and a pump is provided on the flow channel. The control unit controls the pressure in the flow channel by controlling the operation of the pump. When the pressure reaches a certain value, the spray hole 6 opens, otherwise it closes to cut off the fluid supply.

[0026] In some embodiments, Figure 2 As shown, the air inlet 3 of the host 1 is provided with a spray hole 6. In this way, since the temperature gradually rises from the air inlet 3 to the exhaust port 4, it is more conducive to cooling and reducing water vapor residue when it is set at the air inlet 3.

[0027] Further, such as Figure 2 As shown, the spray rod 8 also includes a spray rod 8, and a plurality of spray holes 6 are sequentially arranged along the rod body. The spray rod 8 is extended into the machine body and connected to the machine body. The spray rod 8 is arranged on the air inlet, and the spray holes 6 face the air inlet. This design is convenient for production and manufacturing, and the spray can cool the entire working chamber 12 in the machine body, thereby being more conducive to improving the performance of the vacuum pump.

[0028] Further, such as Figure 2 As shown, the spray rod 8 can be rotated to adjust the direction of the water mist. In this way, the spray rod 8 can be easily adjusted, which is conducive to finding a better spray angle for vacuum pumps of different capacities after a limited number of experiments, so as to adapt to different models. A threaded hole can be set on the machine body, and the spray rod 8 is threadedly connected to the threaded hole, so as to simply achieve the purpose of adjustment.

[0029] In this example, the spray rod 8 is straight, but it can also be S-shaped or other shapes with a larger coverage area. However, after rotation and adjustment, the S-shaped spray rod 8 will not be in the same plane, but will be inclined, while the straight rod can still remain in the same plane.

[0030] Further, such as Figure 1 ,2 As shown, it also includes a temperature detection unit 7, which is used to detect the temperature of the body and / or the exhaust temperature. The temperature detection signal of the temperature detection unit 7 is used for the control unit to determine whether it exceeds the temperature threshold when starting the shutdown program. If it exceeds the temperature threshold, the drive unit 2 is immediately shut down. In this way, when the control unit shuts off the fluid supply, there is no more fluid supplied to the working chamber 12 of the body, but the water vapor detection unit 5 has not yet reached the water vapor detection signal required for shutdown, then the drive unit 2 continues to work, and the female rotor 11 and the male rotor 10 in the working chamber 12 continue to rotate. If the temperature of the body exceeds the temperature threshold at this time, there is a risk of the female rotor 11 and the male rotor 10 scraping the cylinder or biting. Therefore, the present disclosure also has a temperature detection unit 7, which is conducive to improving the shutdown protection performance.

[0031] In some embodiments, Figure 1 As shown, the exhaust port 4 is connected to the exhaust pipe 9, and the water vapor detection unit 5 is located in the exhaust pipe 9. After such a design, it can be away from the exhaust port 4 for a distance. When little water vapor is detected in the exhaust pipe 9, there will be less water vapor in the working chamber 12, so it has better detection performance, which is beneficial to the working reliability of the present disclosure.

[0032] like Figure 3 As shown, when the user uses the shutdown button to shut down the machine, the control unit receives the shutdown signal and then shuts off the fluid supply through the first valve. The drive unit 2 is then controlled by the control unit to enter a shutdown procedure. The drive unit 2 is, for example, an electric motor. The shutdown procedure, for example, reduces the speed of the electric motor and shuts down when the water vapor detection signal reaches the shutdown condition. If the water vapor detection signal does not reach the shutdown condition, but the temperature detection signal reaches the shutdown condition, the drive unit 2 is immediately shut down to prevent the temperature from continuing to rise and causing the female rotor 11 and the male rotor 10 to scrape the cylinder or get stuck.

[0033] The shutdown condition of the water vapor detection signal (ie, the water vapor threshold) can be obtained through a limited number of experiments, and the shutdown condition of the temperature detection signal (ie, the temperature threshold) can also be obtained through a limited number of experiments.

[0034] The water vapor detection unit 5, temperature detection unit 7, first valve, pump, spray nozzles, and control unit can all adopt existing technologies, such as the one-way valve, solenoid valve, etc. of the existing technology, the water vapor detection sensor of the existing technology, the temperature detection sensor of the existing technology, the water pump of the existing technology, the spray nozzle of the existing technology, and the control unit for controlling the opening and closing of the valve, the opening and closing of the pump, and the operation of the electric motor can be a control circuit constructed by a general-purpose single-chip microcomputer.

[0035] When understanding the present invention, if necessary, the above structure can refer to other embodiments / attached Figure 1 And understand, no further elaboration here.

[0036] The above description is only an illustrative embodiment of the present invention, so any equivalent changes or modifications made according to the structure, characteristics and principles described in the patent protection scope of the present invention are included in the patent protection scope of the present invention.

Claims

1. An oil-free vacuum pump shutdown protection system, comprising a control unit, a main unit (1) and a drive unit (2), the main unit (1) comprising an air inlet (3) and an air outlet (4), the control unit being electrically connected to the drive unit (2), the control unit being used to control the drive unit (2) to work, the drive unit (2) being used to drive the main unit (1) to work, characterized in that: A water vapor detection unit (5) is provided at the exhaust port (4), the water vapor detection unit (5) being electrically connected to the control unit, and the water vapor detection unit (5) being used to provide a water vapor detection signal to the control unit, the water vapor detection signal being used by the control unit to determine whether to shut down the drive unit (2) when starting a shutdown program.

2. The oil-free vacuum pump shutdown protection system according to claim 1, characterized in that: The main machine (1) is provided with a water spray hole or a spray hole (6), and the fluid in the water spray hole or the spray hole (6) is controlled to be on and off by a first valve. The first valve is electrically connected to a control unit, and the control unit cuts off the water spray hole or the spray hole (6) from supplying fluid to a working chamber (12) of the main machine (1) when a shutdown procedure is started.

3. An oil-free vacuum pump shutdown protection system according to claim 1 or 2, characterized in that: It also comprises a temperature detection unit (7), which is used to detect the temperature of the machine body and / or the exhaust temperature. The temperature detection signal of the temperature detection unit (7) is used by the control unit to determine whether the temperature exceeds the temperature threshold when starting the shutdown program. If the temperature exceeds the temperature threshold, the drive unit (2) is immediately shut down.

4. The oil-free vacuum pump shutdown protection system according to claim 2, characterized in that: The air inlet (3) of the main machine (1) is provided with a spray hole (6).

5. The oil-free vacuum pump shutdown protection system according to claim 4, characterized in that: It also comprises a spray rod (8), wherein a plurality of spray holes (6) are sequentially arranged along the rod body of the spray rod (8), the spray rod (8) extends into and is connected to the machine body, the spray rod (8) is arranged on the air inlet, and the spray holes (6) face the air inlet.

6. The oil-free vacuum pump shutdown protection system according to claim 1, characterized in that: The spray rod (8) can be rotated to adjust the direction of the water spray.

7. The oil-free vacuum pump shutdown protection system according to claim 1, characterized in that: The exhaust port (4) is connected to an exhaust pipe (9), and the water vapor detection unit (5) is located in the exhaust pipe (9).

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