Shield structure and alternating-current generator

Abstract

The utility model discloses a shield structure and an AC generator, and belongs to the technical field of automobile AC generators, the shield structure comprises a first shield, a second shield and a cleaning structure arranged between the first shield and the second shield, the first shield and the second shield are coaxially arranged, and the axial end faces of the first shield and the second shield are both provided with ventilation holes. The cleaning structure is rotationally mounted on the first protective cover through a connecting shaft, and radial openings of the second protective cover form cleaning holes; the shield structure is mounted at the rear end of the rear end cover of the alternating-current generator, the connecting shaft is in transmission connection with the rotor shaft of the rotor assembly, foreign matters can be filtered in a double-layer manner, the phenomenon that the sweeping structure is broken due to interference of the foreign matters and flies out can be avoided, harms to wire harnesses of an engine or a human body are avoided, and the service life of the engine is prolonged. Meanwhile, swept scraps are swept out through the sweeping holes under the action of gravity and centrifugal force, scrap accumulation is avoided, shield heat dissipation holes are prevented from being blocked, normal operation of a cooling air duct is guaranteed, the service life of the generator is prolonged, and the safety of the generator is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of automobile alternator, and in particular relates to a shield structure and an alternator. Background Art

[0002] Based on the power demand of electrical appliances, motor vehicles are generally equipped with AC generators. Relying on the electromagnetic principle, the mechanical energy of the engine is converted into electrical energy to provide power supply for the electrical appliances and storage batteries of the whole vehicle. The current AC generator cooling method is air cooling, using a centrifugal fan, which rotates at high speed to form a pressure difference, forming air flow in the entire cooling air duct to achieve generator cooling. As the working conditions of the generator become more severe, especially for agricultural machinery, when wheat and corn are harvested, the air is filled with wheat and corn debris. In this way, the debris will be adsorbed to the rear shield of the generator by the pressure difference generated by the centrifugal fan, causing the cooling air duct of the generator to be blocked, the heat dissipation of the generator to fail, and the high temperature failure of the generator heating element.

[0003] In order to solve the above problems, a ventilation shield is set on the outside of the rectifier bridge in the prior art, and a cleaning structure is set on the outside of the ventilation shield, such as the technical solution shown in the patent with authorization announcement number CN212381025U. This structure can effectively prevent large foreign objects, such as wheat ears and straw from entering, but it cannot completely prevent them. In addition, since the cleaning structure fits the shield, the high-speed rotation of the cleaning mechanism and the friction with the shield will generate static electricity, which will accelerate the entry of dust into the generator, thereby affecting the heat dissipation channel of the power generation and reducing the life of the generator. At the same time, the cleaning structure in this structure is exposed to the outside, and it may break and fly out due to interference from foreign objects under high-speed operation, causing damage to the engine wiring harness or personal injury. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a shield structure and an AC generator, which can avoid the risk of a cleaning structure being broken and flying out due to interference from foreign objects when running at high speed, and at the same time avoid the accumulation of debris between the two shield surfaces, prevent the shield heat dissipation holes from being blocked, ensure the normal operation of the cooling air duct, and increase the life of the generator.

[0005] In order to solve the above technical problems, the technical solution of the utility model is:

[0006] A shield structure includes a coaxially arranged first shield, a second shield and a cleaning structure arranged between the first shield and the second shield. The axial end faces of the first shield and the second shield are both provided with ventilation holes. The cleaning structure is rotatably mounted on the first shield via a connecting shaft, and the radial opening of the second shield forms a cleaning hole.

[0007] Furthermore, the cleaning hole is an elongated hole extending along the circumference of the second protective cover.

[0008] Furthermore, the cleaning structure includes a bracket fixed to the connecting shaft and a cylindrical circumferentially surrounding brush head arranged on the bracket.

[0009] Furthermore, there is a gap between the brush head and the axial end faces of the first shield and the second shield, and the gap is greater than 0.1 mm.

[0010] Furthermore, the cleaning surface of the brush head is equidistant from the first protective cover and the second protective cover.

[0011] Furthermore, the distances between the cleaning surface of the brush head and the first protective cover and the second protective cover are not equal.

[0012] Furthermore, the circumferential end face of the second shield is arranged on the outside of the circumferential end face of the first shield, and the first shield and the second shield are respectively provided with a plurality of radial fixing surfaces, and the corresponding radial fixing surfaces are tightly fitted and correspondingly provided with fixing holes for installing bolts.

[0013] An AC generator comprises a front cover, a rear cover, and a rotor assembly and a stator assembly installed between the front cover and the rear cover. The rear end of the rear cover is installed with the above-mentioned shield structure, and the connecting shaft is drivingly connected to the rotor shaft of the rotor assembly.

[0014] After adopting the above technical solution, the beneficial effects of the utility model are:

[0015] Since the shield structure of the utility model includes a first shield, a second shield and a cleaning structure arranged between the first shield and the second shield, the axial end faces of the first shield and the second shield are both provided with ventilation holes, the cleaning structure is rotatably installed on the first shield through a connecting shaft, and the radial opening of the second shield forms a cleaning hole. The first shield and the second shield perform double-layer filtration on foreign matter, which can further prevent debris from entering the cooling air duct; the first shield can protect the cleaning structure to prevent the cleaning structure from breaking and flying out due to interference from foreign matter under high-speed operation, causing damage to the engine wiring harness or personal injury; at the same time, when the cleaning structure is cleaning, the swept debris is cleaned out through the cleaning hole under the action of gravity and centrifugal force, which can avoid the accumulation of debris between the two shield surfaces, prevent the shield heat dissipation holes from being blocked, ensure the normal operation of the cooling air duct, and improve the life of the generator.

[0016] Since the AC generator of the utility model includes a front cover, a rear cover, and a rotor assembly and a stator assembly installed between the front cover and the rear cover, the rear end of the rear cover is installed with the above-mentioned shield structure, and the connecting shaft is transmission-connected to the rotor shaft of the rotor assembly. The shield structure has a good filtering and protection effect, which can effectively prevent debris from clogging the shield heat dissipation holes, ensure the normal operation of the cooling air duct, and improve the life of the generator.

[0017] In summary, the present application solves the technical problems in the prior art that the cleaning structure is in danger of breaking and flying out due to interference from foreign objects and the filtering effect is insufficient when running at high speed. The shield structure and AC generator of the present application can effectively improve the filtering effect, avoid the accumulation of debris between the two shield surfaces, prevent the heat dissipation holes of the shield from being blocked, ensure the normal operation of the cooling air duct, avoid the breaking and flying of the cleaning structure, and improve the service life and safety of the generator. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the protective cover structure of the utility model;

[0019] Figure 2 It is a structural schematic diagram of the utility model AC generator;

[0020] In the figure, 10-first guard shield, 11-connecting shaft, 12-bearing, 13-protective plate, 14-groove, 20-cleaning structure, 21-bracket, 22-brush head, 30-second guard shield, 31-ventilation hole, 32-cleaning hole, 33-radial fixing surface, 34-fixing hole, 40-front end cover, 41-rear end cover, 42-rotor assembly, 43-rotor shaft, 44-stator assembly, 45-fan, 46-pulley. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the protection scope of the present invention.

[0022] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above words in this utility model in combination with the specific content of the technical solution. In the following description, "front end" refers to one end of the AC generator pulley 46, and "rear end" refers to one end of the shield structure.

[0023] Embodiment 1:

[0024] like Figure 1As shown, a shield structure includes a first shield 10, a second shield 30 and a cleaning structure 20 arranged between the first shield 10 and the second shield 30, the axial end faces of the first shield 10 and the second shield 30 are both provided with ventilation holes 31, and the cleaning structure 20 is rotatably mounted on the first shield 10 through a connecting shaft 11. The setting of the double-layer shield can further reduce the foreign matter and dust passing through the shield structure. At the same time, the second shield 30 can protect the cleaning structure 20 to prevent the cleaning mechanism from being broken and flying out due to interference from foreign matter when rotating at high speed, causing damage to the vehicle wiring harness and the human body.

[0025] Furthermore, the radial opening of the second protective cover 30 forms a cleaning hole 32, and the connecting shaft 11 drives the cleaning structure 20 to rotate, thereby cleaning the rotating swept area. The swept debris is thrown out through the cleaning hole 32 under the action of gravity and centrifugal force, thereby achieving the cleaning effect while avoiding the accumulation of debris between the first protective cover 10 and the second protective cover 30.

[0026] Among them, the cleaning hole 32 is an elongated hole extending along the circumference of the second shield 30. The cleaning hole 32 is long enough in the circumference of the second shield 30 to reduce the probability of debris being cleaned onto the circumferential end surface of the second shield 30 and reduce the accumulation of debris.

[0027] like Figure 1 As shown, the cleaning structure 20 includes a bracket 21 fixed to the connecting shaft 11 and a cylindrical circumferentially surrounding brush head 22 arranged on the bracket 21. Among them, the bracket 21 and the brush head 22 can both be preferably made of plastic materials such as nylon and plastic, and the two can be integrally injection molded, and the bracket 21 can be fixed to the connecting shaft 11 by threaded connection.

[0028] There is a gap between the brush head 22 and the axial end faces of the first shield 10 and the second shield 30. Specifically, the gap is greater than 0.1 mm. When the brush head 22 is in contact with the first shield 10 and the second shield 30 or the distance is too close, static electricity will be generated on the shield, which will accelerate dust adsorption, causing dust to enter the generator and block the heat dissipation channel of the generator. When the distance between the brush head 22 and the first shield 10 and the second shield 30 is too far, the brush head 22 has a poor cleaning effect on the axial end faces of the shields. Therefore, in order to ensure the cleaning effect, the gap between the brush head 22 and the axial end faces of the first shield 10 and the second shield 30 is preferably 0.2 to 3 mm.

[0029] In this embodiment, there are many different options for the distance between the cleaning surface of the circumferentially surrounding brush head 22 on the cleaning structure 20, i.e., the two side edges in the axial direction, and the first shield 10 and the second shield 30. In one embodiment, the distance between the cleaning surface of the brush head 22 and the first shield 10 and the second shield 30 is preferably equal.

[0030] In another embodiment, the distances between the cleaning surface of the brush head 22 and the first shield 10 and the second shield 30 may not be equal. Specifically, the distance between the cleaning surface of the brush head 22 and the shields is controlled by adjusting the length of the bristles in the axial direction to achieve better cleaning effects in different application conditions. For example, when used in silage machinery, the debris is usually relatively moist, and a narrower gap distance with the first shield 10 can be selected to prevent the ventilation holes 31 of the first shield 10 from being blocked.

[0031] like Figure 1 As shown, the circumferential end face of the second shield 30 is arranged on the outside of the circumferential end face of the first shield 10, and the first shield 10 and the second shield 30 are respectively provided with a plurality of radial fixing surfaces 33, and the corresponding radial fixing surfaces 33 are tightly fitted, and the relative radial fixing surfaces 33 are correspondingly provided with fixing holes 34 for installing bolts, and the bolts can pass through the fixing holes 34 on the first shield 10 and the second shield 30 at the same time to fix the shield structure to the generator, so as to facilitate quick installation.

[0032] like Figure 1 As shown, the connecting shaft 11 is installed at the center hole of the first protective cover 10 through a bearing 12. A circular groove 14 is provided on the peripheral side of the center hole close to the second protective cover 30. The connecting flange of the protective plate 13 is installed in the groove 14, and the inner wall of the groove 14 is higher than its outer wall, which can effectively prevent dust from entering the bearing 12 through the gap between the connecting shaft 11 and the first protective cover 10, thereby improving the protection effect.

[0033] Embodiment 2:

[0034] like Figure 2 As shown, an AC generator includes a front cover 40, a rear cover 41, and a rotor assembly 42 and a stator assembly 44 installed between the front cover 40 and the rear cover 41. Both ends of a rotor shaft 43 of the rotor assembly 42 extend from the front cover 40 and the rear cover 41 respectively, and a fan 45 and a pulley 46 are connected to the front end of the rotor shaft 43.

[0035] The rear end of the rear cover 41 is equipped with the above-mentioned shield structure, and the rear end of the rotor shaft 43 is transmission-connected with the connecting shaft 11. During the operation of the generator, the torque of the rotor shaft 43 is transmitted to the connecting shaft 11, driving the cleaning structure 20 to rotate for cleaning. The rotor shaft 43 and the connecting shaft 11 can be connected by a hexagon socket fitting, a spline connection or other torque connection structures.

[0036] The utility model provides a second shield on the outside of the first shield and the cleaning structure to prevent the cleaning structure from breaking and flying out, thereby improving the filtering effect and the safety of use. The radial opening of the second shield forms a cleaning hole, so that the swept debris can be cleaned out through the cleaning hole under the action of gravity and centrifugal force, thereby preventing the debris from accumulating between the first shield and the second shield, ensuring the normal operation of the cooling air duct and improving the life of the generator.

[0037] Although the specific implementation methods of the utility model are described above, those skilled in the art should understand that the described embodiments are only part of the implementation methods of the utility model, rather than all the implementation methods, which are only examples, and the protection scope of the utility model is defined by the claims. Those skilled in the art can make various changes or modifications to these implementation methods without departing from the principle and essence of the utility model and without any creative work, but these changes and modifications fall within the protection scope of the utility model.

Claims

1. A shield structure, characterized in that: The invention comprises a first protective cover (10), a second protective cover (30) and a cleaning structure (20) arranged between the first protective cover (10) and the second protective cover (30), wherein the axial end faces of the first protective cover (10) and the second protective cover (30) are both provided with ventilation holes (31), the cleaning structure (20) is rotatably mounted on the first protective cover (10) via a connecting shaft (11), and the radial opening of the second protective cover (30) forms a cleaning hole (32).

2. The shield structure according to claim 1, characterized in that: The cleaning hole (32) is an elongated hole extending along the circumferential direction of the second shield (30).

3. The shield structure according to claim 1, characterized in that: The cleaning structure (20) comprises a bracket (21) fixed to the connecting shaft (11) and a cylindrical circumferentially surrounding brush head (22) arranged on the bracket (21).

4. The shield structure according to claim 3, characterized in that: There is a gap between the brush head (22) and the axial end surfaces of the first protective cover (10) and the second protective cover (30), and the gap is greater than 0.1 mm.

5. The shield structure according to claim 4, characterized in that: The cleaning surface of the brush head (22) is equidistant from the first protective cover (10) and the second protective cover (30).

6. The shield structure according to claim 4, characterized in that: The distances between the cleaning surface of the brush head (22) and the first protective cover (10) and the second protective cover (30) are not equal.

7. The shield structure according to claim 2, characterized in that: The circumferential end face of the second shield (30) is arranged outside the circumferential end face of the first shield (10), and the first shield (10) and the second shield (30) are respectively provided with a plurality of radial fixing surfaces (33), and the corresponding radial fixing surfaces (33) are tightly fitted and correspondingly provided with fixing holes (34) for installing bolts.

8. An AC generator, comprising a front cover (40), a rear cover (41), and a rotor assembly (42) and a stator assembly (44) mounted between the front cover (40) and the rear cover (41), characterized in that: The rear end of the rear end cover (41) is installed with a shield structure according to any one of claims 1 to 7, and the connecting shaft (11) is drivingly connected to the rotor shaft (43) of the rotor assembly (42).

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