Full-flow-section high-efficiency cleaning-free oil bath type pre-filter and control method thereof

Abstract

The application discloses a full-flow-section high-efficiency cleaning-free oil bath type pre-filter, which comprises a pre-filter body, wherein the pre-filter body is a shell with a hollow cavity, the middle part of the shell is provided with an upper filter core and a lower filter core, the hollow cavity in the shell is divided into an upper gas outlet cavity and a lower gas inlet cavity through the upper filter core and the lower filter core, the upper filter core and the lower filter core are oil bath spray chambers, a spraying disc is arranged in the oil bath spray chamber, the bottom of the lower gas inlet cavity is provided with an oil outlet, the upper part of the oil outlet is covered with a gas inlet reflection cover, the side of the upper gas outlet cavity is provided with a gas outlet, the gas inlet of the pre-filter body is a gas inlet pipe, the upper end of the gas inlet pipe is located outside the pre-filter body, the lower end of the gas inlet pipe extends into the lower gas inlet cavity and is connected with the outside through the gas inlet pipe, and the lower end of the gas inlet pipe is located above the gas inlet reflection cover. The spraying system formed by the pre-filter body can greatly prolong the service life of the oil bath filter core, the cleaning effect is judged according to the resistance deterioration coefficient to formulate a cleaning execution scheme, and the filter core is maintained free of maintenance in the life cycle.

Description

Technical Field

[0001] This invention relates to the field of filtration devices, and more specifically to a control method for a high-efficiency, non-cleaning oil bath pre-filter across the entire flow range. Background Technology

[0002] Oil bath air pre-filters are used for pre-filtration of the intake system, with an ideal pre-filtration efficiency of up to 90%. The internal structure of an oil bath air pre-filter, from bottom to top, consists of an oil pan holding the filter oil, and upper and lower metal filter screens. When the engine starts, air enters the oil bath air pre-filter through the intake port. After passing through the centrally located intake duct, the air comes into contact with the oil surface in the oil pan and then flows back into the lower filter element. The oil adhering to the lower filter element adsorbs dust, and the clean air carrying the oil continues upward through the upper filter element, which retains excess oil. However, when the intake airflow is low, there is less oil adhering to the lower filter element, resulting in less contact between the air and the filter oil, leading to insufficient dust adsorption and lower filtration efficiency.

[0003] Air enters the oil bath air pre-filter through the air inlet. After contacting the oil surface in the oil pan through the centrally located air intake, the air is turned back into the lower filter element. The air blows up the oil in the oil pan and attaches it to the lower filter element. The oil attached to the lower filter element absorbs dust. The clean air with oil continues to rise through the upper filter element, which is responsible for leaving the excess oil in the air.

[0004] The disadvantages of existing technology are as follows: 1. Due to the significant difference in airflow required between idle speed and maximum speed during engine operation, insufficient contact between the airflow and oil occurs when the intake airflow is low, resulting in insufficient oil adsorption in the lower filter element and inability to remove much dust, leading to low filtration efficiency. 2. The intake system using an oil bath filter has a high initial resistance, generally ≥3 kPa, with a final alarm pressure of 6.2 kPa. When dust adheres to the lower filter element, the intake resistance increases rapidly, quickly reaching the intake system resistance limit, requiring engine shutdown for filter cleaning or replacement. Furthermore, oil adhering to the metal mesh filter element becomes difficult to clean over time, and direct replacement is costly. Summary of the Invention

[0005] To address the problems of the existing technology, this invention provides a high-efficiency, non-cleaning oil bath pre-filter across the entire flow range and its control method. Based on the traditional oil bath filter, an oil spray chamber is designed for uniform oil spraying. Filtration efficiency is controlled by system flow rate and pressure. Oil is uniformly sprayed into the filter element through a spray pipe. The spray volume is adjusted according to the intake resistance to control the oil concentration inside the filter element, ensuring optimal filtration efficiency. An air reflector is added to the oil pan, which serves only to store oil and reflect intake air. Unlike conventional oil bath filters that rely on intake air blowing up oil from the oil pan and reflecting it onto the filter element, resulting in uncontrollable and uneven oil concentration and significant filtration efficiency variations, this invention adds a spray system to ensure the filter element is always fully coated with oil, maintaining maximum filtration efficiency. Furthermore, after shutdown, the pressure of the oil spray system is adjusted according to the intake system resistance to clean the filter element, achieving a maintenance-free effect while ensuring the intake system resistance remains low.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a high-efficiency, non-cleaning oil bath pre-filter covering the entire flow range, comprising: a pre-filter body, wherein the pre-filter body is a shell with an internal hollow cavity, an upper filter element and a lower filter element are provided in the middle of the shell, the upper filter element and the lower filter element divide the hollow cavity in the shell into an upper air outlet cavity and a lower air inlet cavity, the upper filter element and the lower filter element are spaced apart, the space between the upper filter element and the lower filter element is an oil bath spray chamber, a spray plate is provided in the oil bath spray chamber, an oil outlet is provided at the bottom of the lower air inlet cavity, an air inlet reflector is installed above the oil outlet, an air outlet is provided on the side of the upper air outlet cavity, and an air inlet is provided on the side of the pre-filter body, the air inlet of the pre-filter body is an air inlet pipe, the upper end of the air inlet pipe is located outside the pre-filter body, and the lower end passes through the upper air outlet cavity, the upper filter element, the oil bath spray chamber and the lower filter element in sequence, so that the lower air inlet cavity is connected to the outside through the air inlet pipe, and the lower end of the air inlet pipe is located above the air inlet reflector.

[0007] Furthermore, the top of the air intake reflector is a conical structure, and the bottom is a cylindrical structure, with a notch at the bottom of the cylindrical structure.

[0008] Furthermore, the center of the conical structure at the top of the air intake reflector is on the same straight line as the center of the air intake pipe.

[0009] Furthermore, an air intake cap is provided at one end of the air intake pipe located outside the pre-filter body, and a filter screen is provided in the air intake cap.

[0010] Furthermore, the upper filter element, spray plate, and lower filter element are all provided with through holes for installing air inlet pipes.

[0011] Furthermore, the side surface of the pre-filter body forms an arc-shaped transition with the upper and lower end faces.

[0012] Furthermore, the pre-filter body is a split structure, and the split structures are connected by hinges and quick-release buckles.

[0013] Furthermore, the spray plate includes: a fixed plate and spray pipes. The fixed plate has a hollow structure, and multiple spray pipes are installed on the fixed plate. The oil inlet of the spray pipe extends out of the pre-filter body.

[0014] Furthermore, it also includes: an oil tank, an external filter, an adjustable pressure circulating pump, a pre-filter pressure sensor, an external overpressure sensor, and an intake air temperature sensor. The oil inlet of the adjustable pressure circulating pump is connected to the oil tank via a pipe, and the oil outlet is connected to the spray plate via a pipe. The oil inlet of the external filter is connected to the oil outlet at the bottom of the pre-filter body via a pipe, and the oil outlet is connected to the oil inlet of the oil tank via a pipe. The installation positions of the oil tank and the external filter are lower than the installation position of the pre-filter body. The adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, and the intake air temperature sensor are connected to the vehicle controller. The pre-filter pressure sensor is installed in the pre-filter body to detect whether the lower filter element is clogged. The intake air temperature sensor is installed in the pre-filter body to detect the intake air temperature. The external overpressure sensor is installed in the external filter to detect whether the external filter is clogged. The oil tank, the external filter, the adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, the intake air temperature sensor, the pre-filter body, and the vehicle controller constitute a spray system.

[0015] A control method for a full-flow-range high-efficiency, self-cleaning oil bath pre-filter involves the following steps: After startup, the on-board controller monitors the intake resistance via a pre-filter pressure sensor, reads the intake temperature via an intake temperature sensor, and reads the engine speed via the on-board controller. Simultaneously, the intake resistance values ​​before shutdown and immediately after startup are used to generate the first 20 intake resistance degradation curves, determining the current degradation coefficient φ. n With the degradation coefficient limit φ limit The relationship between them simultaneously determines the current intake resistance F. in With high-efficiency filtration, the intake resistance F min F max The relationship between them; When F in ≥F max , and φ n <φ limit If the cleaning was not thorough during the previous shutdown, the cleaning pressure and time of the adjustable pressure circulation pump will be increased during the next shutdown. When φ n >φ limit When the filter element has reached the end of its service life, it needs to be replaced. When F in ≤F min时If the oil concentration in the lower filter element is insufficient, start the spray system and adjust the spray pressure of the adjustable pressure circulating pump to ensure that F min <F in <F max, When F is in the optimal filtration efficiency range in ≥F max Reduce the spray pressure of the adjustable pressure circulating pump when F in ≤F min Increase the spray pressure of the adjustable pressure circulating pump; When the machine stops, F in =0, start the spray system, adjust the adjustable pressure circulation pump to the cleaning pressure, and rinse the lower filter element. The cleaning pressure is greater than the spray pressure. When the vehicle controller detects that the external filter pressure has reached the limit through the external overpressure sensor, the external filter element should be replaced.

[0016] The beneficial effects of this invention are: (1) The filtration efficiency is not affected by the engine speed and intake flow rate, and the optimal filtration efficiency can be achieved at all gear speeds; the intake system works under the optimal intake resistance for a long time, which brings great benefits to engine combustion and power output; conventional oil bath filter metal filter elements are difficult to clean and need to be replaced frequently. This invention can greatly extend the service life of the oil bath filter element and can achieve maintenance-free operation throughout the entire life cycle. (2) By using the oil spray chamber and air intake reflector, the uncontrollable oil concentration of the filter element, which is usually blown up by air, is made precise and controllable. At the same time, a rigorous judgment logic is designed to keep the filtration efficiency at its best. The filter element spray system is added, and the cleaning effect is judged based on the resistance degradation coefficient to formulate a cleaning execution plan, so that the filter element is maintenance-free during its life cycle. Attached Figure Description

[0017] Figure 1 This is a cross-sectional structural diagram of the present invention; Figure 2 This is a schematic diagram of the spray plate structure; Figure 3 This is a schematic diagram of the air intake reflector. Figure 4 This is a schematic diagram of part of the sprinkler system structure; Figure 5 This is a schematic diagram of the control method flow; In the diagram: 1. Inlet pipe; 2. Outlet; 3. Upper filter element; 4. Oil bath spray chamber; 5. Lower filter element; 6. Lower inlet chamber; 7. Inlet reflector; 8. Spray pipe; 9. Fixed plate; 10. Upper outlet chamber; 11. Inlet cap. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of the invention.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0020] like Figure 1-4 As shown, a high-efficiency, self-cleaning oil bath pre-filter for all flow ranges includes: a pre-filter body, which is a shell with an internal hollow cavity. An upper filter element 3 and a lower filter element 5 are located in the middle of the shell. The upper and lower filter elements 3 and 5 divide the hollow cavity into an upper air outlet cavity 10 and a lower air inlet cavity 6. The upper filter element 3 and the lower filter element 5 are spaced apart, and the space between them is an oil bath spray chamber 4. The oil bath spray chamber 4 contains... The spray plate has an oil outlet at the bottom of the lower air inlet chamber 6, and an air inlet reflector 7 is installed above the oil outlet. An air outlet 2 is provided on the side of the upper air outlet chamber 10. The air inlet of the pre-filter body is an air inlet pipe 1. The upper end of the air inlet pipe 1 is located outside the pre-filter body, and the lower end passes through the upper air outlet chamber 10, the upper filter element 3, the oil bath spray chamber 4, and the lower filter element 5 in sequence, so that the lower air inlet chamber 6 is connected to the outside through the air inlet pipe 1. The lower end of the air inlet pipe 1 is located above the air inlet reflector 7.

[0021] like Figure 1 , 3 As shown, the top of the air intake reflector 7 is a conical structure and the bottom is a cylindrical structure. The bottom of the cylindrical structure is provided with a notch. The air intake enters the lower air intake cavity 6 through the air intake pipe 1, so that the air entering the air intake reflector 7 blows onto the conical structure at the top, and the air flow blowing onto the top of the air intake reflector 7 is dispersed to the surrounding area.

[0022] like Figure 1 As shown, the center of the conical structure at the top of the air intake reflector 7 is on the same straight line as the center of the air intake pipe 1, so that the gas flow blown to the top of the air intake reflector 7 is evenly distributed to the surrounding area.

[0023] like Figure 1 As shown, the side of the pre-filter body and the upper and lower end faces form an arc transition, which can reduce the gas flow resistance in the upper air outlet chamber 10 and the lower air inlet chamber 6 and reduce the occurrence of dead zones.

[0024] like Figure 1 As shown, the pre-filter body has a cylindrical structure with an arc-shaped transition between its side surface and the upper and lower end faces, which can further eliminate the occurrence of gas dead zones.

[0025] like Figure 1 As shown, the air inlet pipe 1 is provided with an air inlet cap 11 at one end outside the pre-filter body. The air inlet cap 11 is provided with a filter screen, which can perform coarse filtration on the incoming gas and also prevent water from entering.

[0026] like Figure 1 As shown, the upper filter element 3, the spray plate, and the lower filter element 5 are all provided with through holes for installing the air inlet pipe 1 to ensure the fit between the upper filter element 3, the spray plate, the lower filter element 5 and the air inlet pipe 1.

[0027] like Figure 1 As shown, the pre-filter body has a split structure, and the split structures are connected by hinges and quick-release buckles. The openings of the split structures are located on the side of the lower filter element 5 or the oil bath spray chamber 4, which facilitates the maintenance and replacement of the upper filter element 3, the spray plate, and the lower filter element 5.

[0028] like Figure 2 As shown, the spray plate includes: a fixed plate 9 and spray pipes 8. The fixed plate 9 has a hollow structure. Multiple spray pipes 8 are installed on the fixed plate 9. The oil inlet of the spray pipe 8 extends out of the pre-filter body. In this example, multiple spray pipes 8 are circumferentially distributed on the fixed plate 9. Multiple nozzles or spray ports are provided on the spray pipes 8.

[0029] like Figure 4 As shown, the full-flow-range high-efficiency, self-cleaning oil bath pre-filter also includes: an oil tank, an external filter, an adjustable pressure circulating pump, a pre-filter pressure sensor, an external overpressure sensor, and an intake air temperature sensor. The oil inlet of the adjustable pressure circulating pump is connected to the oil tank via a pipe, and the oil outlet is connected to the spray plate via a pipe. The oil inlet of the external filter is connected to the oil outlet at the bottom of the pre-filter body via a pipe, and the oil outlet is connected to the oil inlet of the oil tank via a pipe. The installation positions of the oil tank and the external filter are lower than the installation position of the pre-filter body. The adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, and the intake air temperature sensor are connected to the vehicle controller. The pre-filter pressure sensor is installed in the pre-filter body to detect whether the lower filter element 5 is clogged. The intake air temperature sensor is installed in the pre-filter body to detect the intake air temperature. The external overpressure sensor is installed in the external filter to detect whether the external filter is clogged. The oil tank, the external filter, the adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, the intake air temperature sensor, the pre-filter body, and the vehicle controller together form a spray system.

[0030] The vehicle controller is a vehicle-mounted EDU.

[0031] like Figure 5As shown, a control method for a full-flow-range high-efficiency, self-cleaning oil bath pre-filter is described. After startup, the on-board controller monitors the intake resistance via a pre-filter pressure sensor, reads the intake temperature via an intake temperature sensor, and reads the engine speed via the on-board controller. Simultaneously, the intake resistance values ​​before shutdown and immediately after startup are used to generate the first 20 intake resistance degradation curves to determine the current degradation coefficient φ. n With the degradation coefficient limit φ limit The relationship between them simultaneously determines the current intake resistance F. in With high-efficiency filtration, the intake resistance F min F max The relationship between them; When F in ≥F max , and φ n <φ limit If the cleaning was not thorough during the previous shutdown, the cleaning pressure and time of the adjustable pressure circulation pump will be increased during the next shutdown. When φ n >φ limit When the filter element has reached the end of its service life, it needs to be replaced. When F in ≤F min时 If the oil concentration in filter element 5 is insufficient, start the spray system and adjust the spray pressure of the adjustable pressure circulating pump to ensure that F... min <F in <F max, Within the optimal filtration efficiency range; when F in ≥F max Reduce the spray pressure of the adjustable pressure circulating pump when F in ≤F min Increase the spray pressure of the adjustable pressure circulating pump; When the machine stops, F in =0, start the spray system, adjust the adjustable pressure circulation pump to the cleaning pressure, and rinse the lower filter element 5. The cleaning pressure is greater than the spray pressure. When the vehicle controller detects that the external filter pressure has reached the limit through the external overpressure sensor, the external filter element should be replaced.

[0032] The external filter element is a coarse filter with high strength, strong pressure resistance, low cost, and can meet a relatively long replacement cycle.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-efficiency, non-cleaning oil bath pre-filter covering the entire flow range, characterized in that, include: The pre-filter body is a shell with a hollow cavity inside. The shell has an upper filter element and a lower filter element in the middle. The upper and lower filter elements divide the hollow cavity into an upper air outlet cavity and a lower air inlet cavity. The upper and lower filter elements are spaced apart. The space between the upper and lower filter elements is an oil bath spray chamber. The oil bath spray chamber is equipped with a spray plate. The bottom of the lower air inlet cavity is equipped with an oil outlet. An air inlet reflector is installed above the oil outlet. The upper air outlet cavity is equipped with an air outlet on its side. The air inlet of the pre-filter body is an air inlet pipe. The upper end of the air inlet pipe is located outside the pre-filter body. The lower end passes through the upper air outlet cavity, the upper filter element, the oil bath spray chamber, and the lower filter element in sequence, so that the lower air inlet cavity is connected to the outside through the air inlet pipe. The lower end of the air inlet pipe is located above the air inlet reflector. It also includes: an oil tank, an external filter, an adjustable pressure circulating pump, a pre-filter pressure sensor, an external overpressure sensor, and an intake air temperature sensor. The oil inlet of the adjustable pressure circulating pump is connected to the oil tank via a pipe, and the oil outlet is connected to the spray plate via a pipe. The oil inlet of the external filter is connected to the oil outlet at the bottom of the pre-filter body via a pipe, and the oil outlet is connected to the oil inlet of the oil tank via a pipe. The installation positions of the oil tank and the external filter are lower than the installation position of the pre-filter body. The adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, and the intake air temperature sensor are connected to the vehicle controller. The pre-filter pressure sensor is installed in the pre-filter body to detect whether the lower filter element is clogged. The intake air temperature sensor is installed in the pre-filter body to detect the intake air temperature. The external overpressure sensor is installed in the external filter to detect whether the external filter is clogged. The oil tank, the external filter, the adjustable pressure circulating pump, the pre-filter pressure sensor, the external overpressure sensor, the intake air temperature sensor, the pre-filter body, and the vehicle controller together form a spray system. The control method for the full-flow-range high-efficiency, self-cleaning oil bath pre-filter involves the on-board controller monitoring the intake resistance via a pre-filter pressure sensor, reading the intake temperature via an intake temperature sensor, and reading the engine speed via the vehicle controller after startup. Simultaneously, the intake resistance values ​​before shutdown and immediately after startup are used to generate the first 20 intake resistance degradation curves to determine the current degradation coefficient φ. n With the degradation coefficient limit φ limit The relationship between them simultaneously determines the current intake resistance F. in With high-efficiency filtration, the intake resistance F min F max The relationship between them; When F in ≥F max , and φ n <φ limit If the cleaning was not thorough during the previous shutdown, the cleaning pressure and time of the adjustable pressure circulation pump will be increased during the next shutdown. When φ n >φ limit When the filter cartridge has reached the end of its service life, it needs to be replaced. When F in ≤F min时 If the oil concentration in the lower filter element is insufficient, start the spray system and adjust the spray pressure of the adjustable pressure circulating pump to ensure that F min <F in <F max, When F is in the optimal filtration efficiency range in ≥F max Reduce the spray pressure of the adjustable pressure circulating pump when F in ≤F min Increase the spray pressure of the adjustable pressure circulating pump; When the machine stops, F in =0, start the spray system, adjust the adjustable pressure circulation pump to the cleaning pressure, and rinse the lower filter element. The cleaning pressure is greater than the spray pressure. When the vehicle controller detects that the external filter pressure has reached the limit through the external overpressure sensor, the external filter element should be replaced.

2. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 1, characterized in that, The top of the air intake reflector is a conical structure, and the bottom is a cylindrical structure, with an opening at the bottom of the cylindrical structure.

3. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 2, characterized in that, The center of the conical structure at the top of the air intake reflector is on the same straight line as the center of the air intake pipe.

4. The high-efficiency, non-cleaning oil bath pre-filter for the entire flow range according to claim 1, characterized in that, The air intake pipe has an air intake cap at one end located outside the pre-filter body, and a filter screen is installed in the air intake cap.

5. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 1, characterized in that, The upper filter element, spray plate, and lower filter element are all provided with through holes for installing air inlet pipes.

6. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 1, characterized in that, The side of the pre-filter body and the upper and lower end faces form an arc-shaped transition.

7. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 1, characterized in that, The pre-filter body is a split structure, and the split structures are connected by hinges and quick-release buckles.

8. The high-efficiency, non-cleaning oil bath pre-filter for all flow ranges according to claim 1, characterized in that, The spray plate includes a fixed plate and spray pipes. The fixed plate has a hollow structure, and multiple spray pipes are installed on the fixed plate. The oil inlet of the spray pipe extends out of the pre-filter body.

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