Flip type gasoline low-noise generator set

Through the combination of flip-type design and shock-absorbing bracket and muffler, the gasoline generator set has been solved with complex structure, high noise and difficult maintenance, and noise reduction and maintenance convenience are achieved.

CN223062532UActive Publication Date: 2025-07-04SHANGHAI DONMIN POWER EQUIP CO LTD
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Patent Information

Application Number
CN202422408546.2
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-10-08
Publication Date
2025-07-04
Estimated Expiration
2034-10-08

AI Technical Summary

Technical Problem

The existing gasoline generator set has complex structure, high noise and difficulty in repair.

Method used

It adopts a flip-shaped design, with open upper and lower boxes on both sides, and the lids are hinged, combining the shock absorbing bracket, the thermal insulation cotton in the heat dissipation chamber and the muffler, and the thermal insulation cotton in the air guide duct to reduce noise and vibration.

Benefits of technology

The generator set structure is simplified, noise is reduced, maintenance convenience and equipment stability are improved, and service life is extended.

✦ Generated by Eureka AI based on patent content.

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    Figure CN223062532U_ABST
Patent Text Reader

Abstract

The utility model relates to a flip type gasoline low-noise generator set which comprises a box body, the upper side and the lower side of the box body are open, an oil tank is arranged at the bottom of the box body, a gasoline engine is fixed to the oil tank, an electronic oil pump is arranged on the oil tank in a communicating mode, and the electronic oil pump is arranged on an oil inlet of the oil tank and an oil inlet of the gasoline engine in a communicating mode. A power generator is arranged on one side of the gasoline engine, a cooling fan is further arranged on the side, away from the gasoline engine, of the power generator, a cooling cavity is formed in the side, away from the power generator, of the cooling fan of the box body, an exhaust port of the gasoline engine communicates with the cooling cavity, and heat insulation cotton is arranged in the cooling cavity. A silencer is embedded in the heat insulation cotton, the upper side of the box body is further covered with a cover body, and the side, in the horizontal direction, of the cover body is hinged to the box body. The generator set has the advantages that the structure of the generator set is simplified, noise is low, and meanwhile maintenance by workers is facilitated.
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Description

Technical Field

[0001] The present application relates to the technical field of gasoline power generation, and in particular, to a flip - type gasoline low - noise generator set. Background Art

[0002] Currently, with the popularization of new energy vehicles, the usage scenarios of electric vehicles are becoming more and more extensive, which promotes the development of green transportation. However, in scenarios such as long - distance transportation, field operations, and emergency power supply, on - vehicle gasoline generator sets play an important role.

[0003] In related technologies, a gasoline generator set generally includes a gasoline engine and a generator, and the gasoline engine and the generator are drivingly connected.

[0004] In view of the above - mentioned related technologies, the gasoline generator set has problems of complex structure, high noise, and difficult maintenance. Summary of the Invention

[0005] In order to simplify the structure of the generator set, reduce noise, and facilitate maintenance at the same time, the present application provides a flip - type gasoline low - noise generator set.

[0006] A flip - type gasoline low - noise generator set provided by the present application adopts the following technical solutions:

[0007] A flip - type gasoline low - noise generator set includes a box body. Both the upper and lower sides of the box body are open. A fuel tank is provided at the bottom of the box body. A gasoline engine is fixed on the fuel tank. An electronic fuel pump is communicatively connected to the fuel tank. The electronic fuel pump is communicatively connected between the fuel tank and the fuel inlet of the gasoline engine. A generator is provided on one side of the gasoline engine. The generator and the gasoline engine are drivingly connected. A cooling fan is further provided on the side of the generator away from the gasoline engine. A cooling cavity is provided on the side of the box body away from the generator with respect to the cooling fan. The exhaust port of the gasoline engine is communicatively connected to the cooling cavity. Heat - insulating cotton is provided in the cooling cavity, and a muffler is embedded in the heat - insulating cotton. A cover body is further provided on the upper side of the box body. One side of the cover body in the horizontal direction is hinged to the box body.

[0008] By adopting the above - mentioned technical solutions, the open upper and lower sides help to increase the air circulation in the box body. The cover body hinged on the upper side facilitates daily inspection and maintenance by the staff. At the same time, fixing the gasoline engine and the generator on the box body helps to simplify the structure of the entire generator set and increase the gasoline storage capacity. The heat - insulating cotton embedded in the cooling cavity and the muffler communicatively connected to the exhaust port of the gasoline engine help to reduce the noise generated during the operation of the generator set.

[0009] Preferably, a pneumatic rod is provided on the box body. Two ends of the pneumatic rod are respectively hinged to the side wall of the box body and the lower side surface of the cover body.

[0010] By adopting the above technical solution, the pneumatic rod provides support for the opened cover, thereby further facilitating daily inspection and maintenance of the charging unit.

[0011] Preferably, an air duct is provided in the box, one end of the air duct is connected to the exhaust port of the gasoline engine, and the other end is connected to the muffler. The air duct is also filled with heat insulation cotton. The muffler includes an exhaust pipe connected to the muffler, and the exhaust pipe extends out of the box.

[0012] By adopting the above technical solution, the air duct connects the exhaust port and muffler of the gasoline engine, effectively guiding the flow of exhaust gas. The heat insulation cotton arranged in the air duct helps to reduce the noise generated during the exhaust process, while helping to ensure the heat dissipation effect, ensuring that the gasoline engine maintains an appropriate temperature when running at high load, helping to reduce the impact of overheating on power generation efficiency and damage to the service life of equipment.

[0013] Preferably, a base frame is fixed on the oil tank, a shock-absorbing bracket is arranged on the base frame, a support frame is fixed on the shock-absorbing bracket, and the gasoline engine and the generator are both fixed on the support frame.

[0014] By adopting the above technical solution, the shock-absorbing bracket helps to reduce the possibility of vibration generated by the gasoline engine and generator during operation being transmitted to the various brackets and boxes, thereby helping to reduce the noise generated, and at the same time helps to reduce the possibility of failures caused by vibration, helping to improve the safety of the entire generator set.

[0015] Preferably, the shock-absorbing bracket includes a base, the lower end of the base is fixed on the base frame, a support block is provided on the base, the support block slides in the vertical direction, a support spring is provided between the support block and the base, the axial direction of the support spring is vertically arranged, and both ends of the support spring are respectively pressed against the side surfaces of the base and the support block close to each other.

[0016] By adopting the above technical solution, the support spring helps to offset the vibration generated in the vertical direction during the operation of the gasoline engine, thereby helping to reduce the noise generated by the vibration.

[0017] Preferably, the support block also includes a positioning block, one side of the positioning block in the thickness direction is pressed against the upper side surface of the support spring away from the base, a shock-absorbing spring is also provided on the positioning block, and the axial direction of the shock-absorbing spring is inclined in the vertical direction, a support plate is also provided on the top of the shock-absorbing spring, the support plate is horizontally arranged, the support frame is fixed on the support plate, a folding plate is fixed on the lower side of the support plate, the lower side of the folding plate is inclined, an inclined surface is formed on the positioning block, the inclined surface is parallel to the lower side surface of the folding plate, two ends of the shock-absorbing spring are respectively pressed against the inclined surface and the lower side surface of the folding plate, and there are multiple shock-absorbing springs in a circular array around the axis of the support spring.

[0018] By adopting the above technical solution, the inclined shock-absorbing spring helps to offset the vibration in the non-vertical direction transmitted from the support frame to the support plate. Multiple shock-absorbing springs help to disperse the driving force generated by the vibration in each direction. In this way, it helps to reduce the noise generated by the vibration.

[0019] Preferably, the upper half of the folding plate is horizontally arranged, the upper half of the folding plate is relatively fixed to the support plate, the upper half of the folding plate is bent downward along the length direction to form an inclined part, and the folding plate is an elastic member.

[0020] By adopting the above technical solution, the elastic folding plate helps to further reduce the influence of vibration on the support frame and the bottom frame, thereby reducing the noise generated by the vibration.

[0021] Preferably, a positioning stud is fixed on the support plate. The positioning stud is vertically arranged. The positioning stud penetrates through the positioning block in the vertical direction. The positioning block slides along the vertical direction relative to the positioning stud. A positioning nut is also arranged on the positioning stud. The positioning nut is threadedly connected to the positioning stud. The positioning nut is located between the positioning block and the support plate, and the positioning nut is rotatably connected to the positioning block.

[0022] By adopting the above technical solution, the staff can change the compression amount of the support spring by adjusting the relative position of the positioning nut on the positioning stud, thereby changing the pre-tightening force of the support spring. In this way, it helps to adjust the shock-absorbing bracket according to the vibration amplitude of the gasoline engine, and helps to improve the stability of the gasoline engine and the shock-absorbing effect of the shock-absorbing bracket.

[0023] Preferably, a positioning plate is respectively arranged at both horizontal ends of the support plate. A guide post is fixed on the base. A guide hole is vertically penetrated through the positioning plate. The guide hole is sleeved on the guide post. The diameter of the guide hole is larger than the diameter of the guide post. When the support plate slides in the vertical direction, the positioning plate slides in the vertical direction in cooperation with the guide post.

[0024] By adopting the above technical solution, the positioning plate and the guide post help to ensure that the positioning block slides in the vertical direction, help to reduce the situation that the support plate tilts to one side, help to ensure the compression direction of the shock-absorbing spring and the support spring, and help to improve the stability of the shock-absorbing bracket.

[0025] In summary, the present application includes at least one of the following beneficial technical effects:

[0026] 1. A cavity open on both the upper and lower sides and a gasoline engine exhaust port communicatively arranged on the heat dissipation cavity help to improve the heat dissipation effect of the entire generator set while ensuring the exhaust effect. Together with the settings of the muffler and heat insulation cotton, the noise generated by the vibration of the exhaust gas during operation is effectively reduced, so as to ensure that the equipment maintains an appropriate temperature under high-load working conditions and extends the service life;

[0027] 2. The shock-absorbing bracket significantly reduces the impact of vibration on the equipment by reducing the vibration generated by the gasoline engine and the generator during operation. The design of the support spring and the shock-absorbing spring effectively cancels out the vibration, reduces the noise, and enhances the stability of the entire generator set. The shock-absorbing bracket not only reduces the risk of failures caused by vibration but also improves the safety of the entire generator set, making the equipment more reliable in different environments;

[0028] 3. The design of the top flip cover helps the staff to conveniently perform regular inspections and maintenance on the entire generator set. The pneumatic rod provides support for the opened cover body to ensure that the cover body is more stable during the opening and closing processes. Description of the Drawings

[0029] Figure 1 is an axonometric schematic diagram mainly showing the overall structure of the flip-type gasoline low-noise generator set in the embodiment of the present application;

[0030] Figure 2 is an axonometric schematic diagram mainly showing the internal structure of the flip-type gasoline low-noise generator set after the cover body is opened in the embodiment of the present application;

[0031] Figure 3 is an axonometric schematic diagram mainly showing the internal structure of the box body in the embodiment of the present application;

[0032] Figure 4 is an axonometric schematic diagram mainly showing the structure of the shock-absorbing bracket in the embodiment of the present application.

[0033] Reference Signs: 1, box body; 11, fuel filling port; 12, partition board; 13, heat dissipation cavity; 131, lug; 132, muffler; 133, exhaust pipe; 14, electric control box; 15, inspection door; 2, cover body; 21, ventilation port; 22, pneumatic rod; 3, fuel tank; 31, fuel filling pipe; 4, chassis; 5, shock-absorbing bracket; 51, base; 52, anti-slip pad; 53, guide post; 54, support spring; 55, support block; 551, positioning block; 552, support plate; 553, positioning plate; 554, guide hole; 56, positioning stud; 561, locking nut; 57, folding plate; 58, shock-absorbing spring; 6, support frame; 7, gasoline engine; 71, air guide duct; 8, generator; 9, heat dissipation fan. Detailed Embodiments

[0034] The following is combined with the attachedFigures 1-4 This application is described in further detail.

[0035] The embodiment of the present application discloses a clamshell gasoline low-noise generator set.

[0036] See also Figure 1 , Figure 2 The flip-top gasoline low-noise generator set includes a box body 1, the upper and lower sides of the box body 1 are open, a cover body 2 is arranged on the upper side of the box body 1, the cover body 2 is arranged corresponding to the box body 1, and one side of the cover body 2 in the width direction is hinged to the box body 1. A gas pressure rod 22 is also arranged on the side wall of the box body 1 near the hinge, and the two ends of the gas pressure rod 22 are respectively hinged to the lower side of the cover body 2 and the side wall of the box body 1. The staff can inspect and maintain the equipment in the box body 1 by lifting the upper cover body 2. The gas pressure rod 22 supports the opened cover body 2, which helps to reduce the possibility of the cover body 2 hitting the box body 1 due to gravity, thereby helping to improve safety.

[0037] See also Figures 2-4 The bottom of the box body 1 is provided with a fuel tank 3, and the two sides of the fuel tank 3 along the width direction of the box body 1 are relatively fixed to the box body 1. The box body 1 is provided with a refueling port 11, and a refueling pipe 31 is connected to the refueling port 11, and the refueling pipe 31 is connected to the fuel tank 3. A base frame 4 is fixed on the upper side of the fuel tank 3, and a shock-absorbing bracket 5 is provided on the base frame 4. The shock-absorbing bracket 5 includes a base 51, and a non-slip pad 52 is fixed to the lower side of the base 51, and the base 51 is fixedly connected to the base frame 4.

[0038] A support spring 54 is arranged on the base 51, and the axis direction of the support spring 54 is arranged vertically. A support block 55 is arranged on the upper end of the support spring 54, and the support block 55 includes a positioning block 551 and a support plate 552. The upper end of the support spring 54 is pressed against the lower side of the positioning block 551. A plurality of inclined surfaces arranged in an array around the axis direction of the support spring 54 are formed on the upper side of the positioning block 551, so that the positioning block 551 shrinks from bottom to top. A damping spring 58 is arranged on any inclined surface, and the axis direction of any damping spring 58 is perpendicular to the corresponding inclined surface. The side of the damping spring 58 away from the inclined surface is a free folding plate 57, and the upper half of the folding plate 57 is arranged horizontally. The upper half of the folding plate 57 extends along its own length direction toward the direction close to the axis of the support spring 54 and bends downward to form an inclined lower half. The lower side of the folding plate 57 is parallel to the inclined surface, and the upper side of the damping spring 58 is pressed against the lower side of the folding plate 57. Both ends of the support spring 54 and the damping spring 58 are provided with mounting sleeves for positioning, and the mounting sleeves are fixedly connected to the corresponding abutting parts.

[0039] The support plate 552 is arranged on the upper side of all the folding plates 57, and the support plate 552 is arranged horizontally. The support plate 552 is fixedly connected to any folding plate 57, and all the folding plates 57 are elastic members. The support plate 552 is also provided with a positioning stud 56, which is arranged vertically. The positioning stud 56 penetrates the positioning block 551 along its own axis direction, and the positioning block 551 slides with the positioning stud 56 along the vertical direction. The positioning stud 56 is also sleeved with a positioning nut, which is located between the positioning block 551 and the support plate 552, and the positioning nut is rotatably connected to the positioning block 551. The staff can change the relative distance between the positioning block 551 and the base 51 by adjusting the relative position of the positioning nut on the positioning stud 56. In this way, the compression amount of the support spring 54 can be changed, thereby changing the preload force of the support spring 54.

[0040] The support plate 552 is fixed with positioning plates 553 at both ends along the length direction of the base 51, and the positioning plates 553 are arranged horizontally. Two guide posts 53 are arranged on the base 51, and any guide post 53 is arranged vertically. A guide hole 554 is opened on any positioning plate 553, and the guide hole 554 passes through the corresponding positioning plate 553 in the vertical direction. Any guide post 53 is inserted into the corresponding guide hole 554, and the diameter of the guide hole 554 is larger than the diameter of the guide post 53. The positioning plate 553 is slidably matched with the guide post 53 in the vertical direction.

[0041] The positioning stud 56 is also provided with a locking nut 561, which is threadedly connected to the positioning stud 56. A support frame 6 is also provided on the support plate 552, and the locking nut 561 is located on the upper side of the support frame 6, and the lower side of the locking nut 561 is pressed against the upper side of the support frame 6. A shock-absorbing bracket 5 is provided at each of the four corners of the positioning frame, which helps to ensure the stability of the four corners of the positioning frame in the horizontal direction.

[0042] A partition 12 is arranged in the box body 1, and the partition 12 is arranged vertically, and the thickness direction of the partition 12 is parallel to the length direction of the box body 1. A heat dissipation cavity 13 is formed between the partition 12 and the side plate of the box body 1 on the side close to the partition 12 in the length direction, and the oil tank 3 is arranged on the side of the box body 1 away from the heat dissipation cavity 13. A gasoline engine 7 is fixed on the support frame 6, and the gasoline engine 7 is arranged on the side of the box body 1 in the length direction away from the heat dissipation cavity 13. A generator 8 is also fixed on the support frame 6, and the generator 8 is connected to the gasoline engine 7 by transmission, and the generator 8 is located on the side of the gasoline engine 7 close to the heat dissipation cavity 13. A heat dissipation fan 9 is embedded in the partition 12, and the heat dissipation fan 9 is connected to the generator 8 by transmission. The heat dissipation fan 9 points into the heat dissipation cavity 13.

[0043] A mounting frame is fixed on the side wall of the box body 1, and an electronic oil pump is fixed on the mounting frame. The electronic oil pump is connected between the oil tank 3 and the gasoline engine 7 respectively.

[0044] An air duct 71 is also provided on the upper side of the generator 8. One end of the air duct 71 in the length direction is connected to the exhaust port of the gasoline generator 8. The air duct 71 is internally embedded with heat insulation cotton. A plurality of lugs 131 are fixed on the inner side wall of the heat dissipation cavity 13, and heat insulation cotton is also provided in the heat dissipation cavity 13. The heat insulation cotton is fixed in the heat dissipation cavity 13 through the lugs 131. A muffler 132 is embedded in the heat insulation cotton. The side of the air duct 71 facing away from the gasoline engine 7 is connected to the muffler 132, and an exhaust pipe 133 is also connected to the muffler 132. The exhaust pipe 133 extends upward out of the box body 1.

[0045] See Figure 1 , Figure 2 , a ventilation opening 21 is correspondingly provided on the cover body 2. The ventilation opening 21 is located on the upper side of the heat dissipation cavity 13, and the ventilation opening 21 penetrates through the cover body 2.

[0046] An electric control box 14 is also provided on the side of the box body 1 facing away from the heat dissipation cavity 13. Devices such as an electric control switch and a circuit board are provided in the electric control box 14. The electric control switch is electrically connected to the gasoline engine 7 and the generator 8. Workers can electrically connect the external line to the internal line of the generator set through the electric control box 14. A plurality of maintenance doors 15 are also provided on the side of the box body 1.

[0047] The implementation principle of a flip-type gasoline low-noise generator set in an embodiment of the present application is as follows: Workers inject gasoline into the fuel tank 3 through the fuel filling port 11. The electric fuel pump drives the gasoline in the fuel tank 3 into the gasoline engine 7. The gasoline engine 7 starts, converts heat energy into kinetic energy through the operation of the internal combustion engine, and then transmits it to the generator 8 to convert kinetic energy into electrical energy, thereby realizing power generation. At the same time, the generator 8 is drivingly connected to the heat dissipation fan 9, and the generator 8 drives the heat dissipation fan 9 to move. The heat dissipation fan 9 inhales the relatively low-temperature air from the upper and lower sides into the box body 1, passes through the relatively high-temperature gasoline engine 7 and generator 8, and then discharges it from the upper and lower sides of the heat dissipation cavity 13. The heat insulation cotton in the heat dissipation cavity 13 and the muffler 132 embedded in the heat insulation cotton help to reduce the air vibration generated by the exhaust of the gasoline engine 7, thereby helping to reduce noise. The shock-absorbing bracket 5 helps to reduce the noise generated by the vibration during the operation of the gasoline engine 7 and the generator 8, and at the same time helps to protect the safety of the entire generator set. The flip-up cover body 2 helps to facilitate the maintenance and repair of the entire generator set by workers.

[0048] The above are all preferred embodiments of the present application. The protection scope of the present application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A flip - type gasoline low - noise generator set, characterized in that: The invention comprises a box body (1), wherein both upper and lower sides of the box body (1) are open, a fuel tank (3) is arranged at the bottom of the box body (1), a gasoline engine (7) is fixed on the fuel tank (3), an electronic fuel pump is arranged on the fuel tank (3) in communication, and the electronic fuel pump is arranged in communication with the fuel tank (3) and the fuel inlet of the gasoline engine (7), a generator (8) is arranged on one side of the gasoline engine (7), the generator (8) and the gasoline engine (7) are transmission-connected, a heat dissipation fan (9) is also arranged on the side of the generator (8) away from the gasoline engine (7), a heat dissipation cavity (13) is arranged on the side of the heat dissipation fan (9) away from the generator (8), an exhaust port of the gasoline engine (7) is communicated with the heat dissipation cavity (13), a heat insulation cotton is arranged in the heat dissipation cavity (13), a muffler (132) is embedded in the heat insulation cotton, and a cover body (2) is also provided on the upper side of the box body (1), and one side of the cover body (2) in the horizontal direction is hinged to the box body (1).

2. The flip - type gasoline low - noise generator set according to claim 1, wherein: The box body (1) is provided with a gas pressure rod (22), and two ends of the gas pressure rod (22) are respectively hinged to the side wall of the box body (1) and the lower side of the lid.

3. The flip - type gasoline low - noise generator set according to claim 1, wherein: An air guide duct (71) is arranged in the box (1); one end of the air guide duct (71) is connected to the exhaust port of the gasoline engine (7), and the other end is connected to the muffler (132); the air guide duct (71) is also filled with heat insulation cotton; the muffler (132) includes an exhaust pipe connected to the muffler (132), and the exhaust pipe extends out of the box (1).

4. A flip - type gasoline low - noise generator set according to claim 1, characterized in that: A base frame (4) is fixed on the oil tank (3), a shock absorbing bracket (5) is provided on the base frame (4), a support frame (6) is fixed on the shock absorbing bracket (5), and the gasoline engine (7) and the generator (8) are both fixed on the support frame (6).

5. A flip - type gasoline low - noise generator set according to claim 4, characterized in that: The shock-absorbing bracket (5) comprises a base (51), the lower end of the base (51) is fixed on the base frame (4), a support block (55) is arranged on the base (51), the support block (55) slides in the vertical direction, a support spring (54) is arranged between the support block (55) and the base (51), the axis direction of the support spring (54) is arranged vertically, and two ends of the support spring (54) are respectively pressed against the side surfaces of the base (51) and the support block (55) that are close to each other.

6. The flip - type gasoline low - noise generator set according to claim 5, wherein: The support block (55) further comprises a positioning block (551), one side of the positioning block (551) in the thickness direction is pressed against the upper side surface of the support spring (54) away from the base (51), the positioning block (551) is further provided with a shock absorbing spring (58), the axis direction of the shock absorbing spring (58) being inclined in the vertical direction, a support plate (552) is further provided on the top of the shock absorbing spring (58), the support plate (552) being arranged horizontally, the support frame (6) is fixed on the support plate (552), a folding plate (57) is fixed on the lower side of the support plate (552), the lower side of the folding plate (57) being arranged inclined, an inclined surface is formed on the positioning block (551), the inclined surface is parallel to the lower side surface of the folding plate (57), two ends of the shock absorbing spring (58) are respectively pressed against the inclined surface and the lower side surface of the folding plate (57), and a plurality of shock absorbing springs (58) are arranged in a circular array around the axis of the support spring (54).

7. The flip - type gasoline low - noise generator set according to claim 6, characterized in that: The upper part of the folding plate (57) is arranged horizontally, the upper part of the folding plate (57) is relatively fixed to the support plate (552), the upper part of the folding plate (57) is bent downward along the length direction to form an inclined part, and the folding plate (57) is an elastic member.

8. The flip - type gasoline low - noise generator set according to claim 7, wherein: A positioning stud (56) is fixed on the support plate (552). The positioning stud (56) is arranged vertically. The positioning stud (56) passes through the positioning block (551) in the vertical direction. The positioning block (551) slides with the positioning stud (56) in the vertical direction. A positioning nut is also arranged on the positioning stud (56). The positioning nut is threadedly connected to the positioning stud (56). The positioning nut is located between the positioning block (551) and the support plate (552). The positioning nut is rotatably connected to the positioning block (551).

9. A flip - type gasoline low - noise generator set according to claim 8, wherein: A positioning plate (553) is also provided at both ends of the support plate (552) in the horizontal direction. A guide column (53) is fixed on the base (51). A guide hole (554) is provided through the positioning plate (553) in the vertical direction. The guide hole (554) is sleeved on the guide column (53). The diameter of the guide hole (554) is larger than the diameter of the guide column (53). When the support plate (552) slides in the vertical direction, the positioning plate (553) slides and cooperates with the guide column (53) in the vertical direction.