Automatic pressure relief structure of air pump

Abstract

The utility model discloses an automatic pressure relief structure of an air pump. The automatic pressure relief structure comprises an air pump cylinder cover, a pressure relief valve and a pressure relief air channel, the air pump cylinder cover is arranged at the crankcase, an air pump pressure chamber is arranged between the air pump cylinder cover and the crankcase, the air pump cylinder cover comprises a pressure release valve mounting part, and the pressure release valve mounting part is communicated with the air pump pressure chamber; the pressure release valve is arranged at the pressure release valve mounting part; the pressure relief air channel is arranged in the air pump cylinder cover and communicates with the interior of the crankcase. When the gas pressure in the gas pump pressure chamber is larger than a set value, the pressure release valve is opened, and gas can be discharged into the crankcase through the pressure release valve and the pressure release gas channel. According to the automatic pressure relief structure of the air pump, the problem that the pumping pressure in the take-off stage of the unmanned aerial vehicle is high can be solved through a certain pumping pressure threshold value, and therefore the power reliability of the unmanned aerial vehicle is improved.

Description

Technical Field

[0001] The utility model relates to the field of engine design and manufacturing, in particular to an automatic pressure relief structure of an air pump of an engine. Background Art

[0002] The air-entrained direct injection system is a new type of fuel injection system. Under low oil pressure, it uses gas-liquid two-phase cavitation and other effects to atomize the fuel into extremely fine droplets at high speed and evaporate quickly, achieving a good atomization effect of heavy oil. Its excellent heavy oil atomization ability and high lightweight characteristics are widely used in heavy oil engines for small and medium-sized UAVs. Its characteristics are that the air-entrained direct injection system consists of a fuel nozzle and an air-entrained direct injection nozzle. The injection pressure of the fuel nozzle is provided by the fuel pump, and the injection pressure of the air-entrained direct injection nozzle is provided by the air pump. Therefore, the air-entrained direct injection system requires an additional matching air pump, which provides air with a certain flow and pressure for the air-entrained direct injection system.

[0003] Since the working environment of drones is generally above 3000m in the air, the pump air pressure of the air pump will decrease with the increase of altitude. In order to ensure the power performance of the drone at high altitude, the pump air pressure of the air pump needs to be designed with a certain margin, resulting in a higher pump air pressure during the drone's take-off phase, affecting the reliability of the drone's power.

[0004] In view of this, the need to take effective measures to overcome the above problems has become one of the issues that need to be urgently addressed in the industry.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to a person skilled in the art. Utility Model Content

[0006] The utility model aims to provide an automatic pressure relief structure of an air pump, which can control the problem of high pump air pressure during the take-off phase of a UAV through a certain pump air pressure threshold, thereby improving the reliability of the UAV power.

[0007] To achieve the above-mentioned purpose, the utility model provides an automatic pressure relief structure of an air pump, comprising an air pump cylinder head, a pressure relief valve and a pressure relief air duct; the air pump cylinder head is arranged at the crankcase, an air pump pressure chamber is included between the air pump cylinder head and the crankcase, the air pump cylinder head includes a pressure relief valve mounting portion, and the pressure relief valve mounting portion is connected to the air pump pressure chamber; the pressure relief valve is arranged at the pressure relief valve mounting portion; the pressure relief air duct is arranged in the air pump cylinder head, and the pressure relief air duct is connected to the inside of the crankcase; when the gas pressure in the air pump pressure chamber is greater than the set value, the pressure relief valve opens, and the gas will be discharged into the crankcase through the pressure relief valve and the pressure relief air duct.

[0008] In a preferred embodiment, the pressure relief valve mounting portion is a pressure relief valve mounting hole, and a lower end of the pressure relief valve mounting hole is communicated with the air pump pressure chamber.

[0009] In a preferred embodiment, the pressure relief valve includes a valve body, a steel ball, a spring and an adjusting body; the valve body is arranged in the pressure relief valve mounting hole, the valve body includes a pressure relief chamber, and the lower part of the pressure relief chamber is connected with the air pump pressure chamber through the pressure relief valve mounting hole; the steel ball is arranged at the bottom of the pressure relief chamber, and the steel ball can control the connection or closing of the pressure relief chamber and the pressure relief valve mounting hole; one end of the spring is against the steel ball; the adjusting body is arranged at the upper part of the pressure relief chamber and pressed on the spring, the adjusting body includes a pressure relief hole, which is connected between the pressure relief chamber and the pressure relief airway; wherein the tension of the spring controls the opening pressure of the pressure relief valve.

[0010] In a preferred embodiment, the valve body and the mounting hole of the pressure relief valve are connected by interference fit, threaded connection or clamping.

[0011] In a preferred embodiment, the adjusting body and the pressure relief hole are connected by threads.

[0012] In a preferred embodiment, the pressure relief valve also includes a pointer mark and a pressure scale mark; the pointer mark is arranged on the top surface of the adjustment body; the pressure scale mark is arranged on the top surface of the valve body; wherein the pointer mark and the pressure scale mark cooperate to intuitively display the opening setting value of the pressure relief valve.

[0013] In a preferred embodiment, the automatic pressure relief structure of the air pump also includes a pressure relief valve cover, which is arranged on the air pump cylinder head. The pressure relief valve cover includes a pressure relief chamber, which is connected to the pressure relief cavity through the pressure relief hole and is also connected to the pressure relief airway.

[0014] In a preferred embodiment, the automatic pressure relief structure of the air pump further includes an air pump pressure outlet, which is arranged at the lower part of the pressure relief chamber, and the position of the air pump pressure outlet is located outside the bottom end of the valve body.

[0015] In a preferred embodiment, the pressure relief valve cover is fixedly connected to the air pump cylinder cover by bolts.

[0016] In a preferred embodiment, the air pump cylinder head is fixedly connected to the crankcase by bolts.

[0017] Compared with the prior art, the automatic pressure relief structure of the air pump of the utility model has the following beneficial effects: the application sets a pressure relief valve in the air pump cylinder head of the air pump, and the pressure relief valve can control the connection or closure between the air pump pressure chamber and the pressure relief air duct. When the air pressure in the air pump pressure chamber is greater than the set value, the pressure relief valve automatically opens to allow the gas in the air pump pressure chamber to return to the crankcase through the pressure relief valve and the pressure relief air duct, thereby achieving effective control of the air pump outlet pressure and effective utilization of the air pump energy, avoiding the problem of high pump air pressure during the take-off stage of the UAV, thereby improving the reliability of the UAV power. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic cross-sectional view of an automatic pressure relief structure according to one embodiment of the utility model;

[0019] Figure 2 It is a schematic diagram of the test structure of the automatic pressure relief structure according to one embodiment of the utility model;

[0020] Figure 3 It is a schematic diagram of the installation structure of the automatic pressure relief structure and the crankcase according to one embodiment of the utility model;

[0021] Figure 4 It is a schematic diagram of the top structure of a pressure relief valve according to one embodiment of the utility model.

[0022] Description of main reference numerals:

[0023] 1-air pump cylinder head, 11-air pump pressure chamber, 12-pressure relief valve mounting hole, 13-air pump pressure outlet, 14-pressure relief air duct, 2-pressure relief valve cover, 3-pressure relief valve, 301-valve body, 3011-pressure scale mark, 302-steel ball, 303-spring, 304-adjustment body, 3041-pointer mark, 4-crankcase. DETAILED DESCRIPTION

[0024] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0025] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0026] like Figures 1 to 3 As shown, according to a preferred embodiment of the utility model, an automatic pressure relief structure of an air pump includes an air pump cylinder head 1, a pressure relief valve 3 and a pressure relief air duct 14; the air pump cylinder head 1 is arranged at the crankcase 4, and an air pump pressure chamber 11 is included between the air pump cylinder head 1 and the crankcase 4, and the air pump cylinder head 1 includes a pressure relief valve mounting portion, and the pressure relief valve mounting portion is connected to the air pump pressure chamber 11; the pressure relief valve 3 is arranged at the pressure relief valve mounting portion; the pressure relief air duct 14 is arranged in the air pump cylinder head 1, and the pressure relief air duct 14 is connected to the inside of the crankcase 4; when the gas pressure in the air pump pressure chamber 11 is greater than the set value, the pressure relief valve 3 is opened, and the gas will be discharged into the crankcase 4 through the pressure relief valve 3 and the pressure relief air duct 14.

[0027] In some implementations, the pressure relief valve mounting portion of this embodiment is in the form of a pressure relief valve mounting hole 12 , and the lower end of the pressure relief valve mounting hole 12 is communicated with the air pump pressure chamber 11 .

[0028] See also Figure 1 In some embodiments, the pressure relief valve 3 includes a valve body 301, a steel ball 302, a spring 303 and an adjustment body 304; the valve body 301 is arranged in the pressure relief valve mounting hole 12, the valve body 301 includes a pressure relief chamber, and the lower part of the pressure relief chamber is connected to the air pump pressure chamber 11 through the pressure relief valve mounting hole 12; the pressure relief chamber of this embodiment adopts the form of a stepped hole, the upper diameter of the stepped hole is larger than the lower diameter, and a tapered hole is used to transition between the upper and lower sections; the steel ball 302 is arranged at the tapered hole at the bottom of the pressure relief chamber, and the steel ball 302 can control the connection or closure of the pressure relief chamber and the pressure relief valve mounting hole 12; one end of the spring 303 is against the steel ball 302; the adjustment body 304 is arranged at the upper part of the pressure relief chamber and is pressed on the spring 303, the adjustment body 304 includes a pressure relief hole, and the pressure relief hole is connected between the pressure relief chamber and the pressure relief airway 14; wherein the tension of the spring 303 controls the opening pressure of the pressure relief valve 3.

[0029] In some embodiments, the valve body 301 and the pressure relief valve mounting hole 12 may be connected by interference fit, threaded connection or snap-fit. When threaded connection or snap-fit ​​is used, a sealing ring is required for sealing.

[0030] In some embodiments, the adjusting body 304 and the pressure relief hole are connected by threads, and a sealing ring is also required for sealing.

[0031] like Figure 4 As shown, in some embodiments, the pressure relief valve 3 further includes a pointer mark 3041 and a pressure scale mark 3011; the pointer mark 3041 is arranged on the top surface of the adjustment body 304; the pressure scale mark 3011 is arranged on the top surface of the valve body 301; wherein the pointer mark 3041 cooperates with the pressure scale mark 3011 to intuitively display the opening setting value of the pressure relief valve 3. The pressure scale mark 3011 can be converted by the pitch of the thread, the tension of the spring 303, and the compression distance of the spring 303. The tension of the spring 303 is converted from the free length to the compression length of the spring 303, and then converted into an angle by the pitch. The pointer mark 3041 points to a certain point of the pressure scale mark 3011, which indicates the current opening pressure value of the pressure relief valve 3. The pointer mark 3041 and the pressure scale mark 3011 are only for the convenience of simple setting of the pressure relief setting value. The utility model is not limited to this, and other feasible methods can also be used to set the opening pressure of the pressure relief valve 3.

[0032] In some embodiments, the automatic pressure relief structure of the air pump also includes a pressure relief valve cover 2, which is arranged on the air pump cylinder head 1. The pressure relief valve cover 2 includes a pressure relief chamber, which is connected to the pressure relief cavity through the pressure relief hole and is also connected to the pressure relief airway 14.

[0033] In some embodiments, the automatic pressure relief structure of the air pump also includes an air pump pressure outlet 13, which is arranged at the lower part of the pressure relief chamber. The position of the air pump pressure outlet 13 is located outside the bottom end of the valve body 301, and the air pump pressure outlet 13 is connected to the direction of the air-entrained direct injection nozzle.

[0034] In some embodiments, the connection between the pressure relief valve cover 2 and the air pump cylinder head 1 and the connection between the air pump cylinder head 1 and the crankcase 4 can be fixed by bolts.

[0035] In some embodiments, the working principle of the automatic pressure relief structure of the air pump of the utility model is as follows: when the drone just takes off, because it is flying in low altitude, the air density in low altitude is relatively large, and the pumping pressure of the air pump is easy to increase and exceed the set value. At this time, the gas pressure in the air pump pressure chamber 11 is greater than the opening pressure of the pressure relief valve 3. The steel ball 302 moves upward under the action of the gas pressure to overcome the tension of the spring 303. The gas in the air pump pressure chamber 11 can pass through the pressure relief valve mounting hole 12, the pressure relief cavity, the pressure relief hole, and the pressure relief chamber of the pressure relief valve cover, and then be discharged from the pressure relief airway into the crankcase 4. When the drone rises to high altitude, due to the low air density in high altitude, the pumping pressure of the air pump is not easy to exceed the set value, and the working efficiency of the air pump can be better exerted at this time.

[0036] To sum up, the automatic pressure relief structure of the air pump of the utility model has the following advantages: the application sets a pressure relief valve in the air pump cylinder head of the air pump, and the pressure relief valve can control the connection or closure between the air pump pressure chamber and the pressure relief air duct. When the air pressure in the air pump pressure chamber is greater than the set value, the pressure relief valve automatically opens, so that the gas in the air pump pressure chamber returns to the crankcase through the pressure relief valve and the pressure relief air duct, thereby realizing effective control of the air pump outlet pressure and realizing effective utilization of the air pump energy, avoiding the problem of high pump air pressure during the take-off stage of the UAV, thereby improving the reliability of the UAV power.

[0037] The foregoing description of specific exemplary embodiments of the utility model is for the purpose of illustration and illustration. These descriptions are not intended to limit the utility model to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the utility model and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the utility model and various different options and changes. The scope of the utility model is intended to be defined by the claims and their equivalents.

Claims

1. An automatic pressure relief structure of an air pump, characterized in that: include: An air pump cylinder head, which is arranged at the crankcase, comprises an air pump pressure chamber between the air pump cylinder head and the crankcase, and comprises a pressure relief valve mounting portion, wherein the pressure relief valve mounting portion is in communication with the air pump pressure chamber; a pressure relief valve, which is arranged at the pressure relief valve installation portion; and A pressure relief air passage, which is arranged in the air pump cylinder head and communicated with the interior of the crankcase; When the gas pressure in the air pump pressure chamber is greater than a set value, the pressure relief valve opens, and the gas is discharged into the crankcase through the pressure relief valve and the pressure relief air passage.

2. The automatic pressure relief structure of the air pump according to claim 1, characterized in that: The pressure relief valve mounting portion is a pressure relief valve mounting hole, and a lower end of the pressure relief valve mounting hole is communicated with the air pump pressure chamber.

3. The automatic pressure relief structure of the air pump according to claim 2, characterized in that: The pressure relief valve comprises: A valve body, which is arranged in the pressure relief valve installation hole, the valve body includes a pressure relief chamber, and the lower part of the pressure relief chamber is connected with the air pump pressure chamber through the pressure relief valve installation hole; A steel ball, which is arranged at the bottom of the pressure relief chamber, and the steel ball can control the connection or closing of the pressure relief chamber and the pressure relief valve installation hole; a spring, one end of which abuts against the steel ball; and An adjusting body, which is arranged at the upper part of the pressure relief chamber and pressed on the spring, and the adjusting body includes a pressure relief hole, which is connected between the pressure relief chamber and the pressure relief airway; The tension of the spring controls the opening pressure of the pressure relief valve.

4. The automatic pressure relief structure of the air pump according to claim 3, characterized in that: The valve body and the pressure relief valve mounting hole are connected by interference fit, threaded connection or clamping.

5. The automatic pressure relief structure of the air pump according to claim 3, characterized in that: The adjusting body and the pressure relief hole are connected by threads.

6. The automatic pressure relief structure of the air pump according to claim 5, characterized in that: The pressure relief valve further comprises: a pointer mark disposed on the top surface of the adjustment body; and a pressure scale mark, which is arranged on the top surface of the valve body; The pointer mark cooperates with the pressure scale mark to intuitively display the opening setting value of the pressure relief valve.

7. The automatic pressure relief structure of an air pump as claimed in claim 3, characterized in that: It also includes a pressure relief valve cover, which is arranged on the air pump cylinder head. The pressure relief valve cover includes a pressure relief chamber. The pressure relief chamber is connected to the pressure relief cavity through the pressure relief hole and is also connected to the pressure relief airway.

8. The automatic pressure relief structure of an air pump as claimed in claim 3, characterized in that: It also includes an air pump pressure outlet, which is arranged at the lower part of the pressure relief chamber, and the position of the air pump pressure outlet is located outside the bottom end of the valve body.

9. The automatic pressure relief structure of an air pump according to claim 7, characterized in that: The pressure relief valve cover is fixedly connected to the air pump cylinder cover by bolts.

10. The automatic pressure relief structure of an air pump according to claim 1, characterized in that: The air pump cylinder head is fixedly connected to the crankcase by bolts.

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