Explosion-proof motor structure

Abstract

An explosion-proof motor structure relates to the technical field of motors and can reach the IP56 protection level, and spark, electric arc or dangerous temperature which is enough to cause explosion danger is not generated in a motor junction box. And meanwhile, a relatively large margin is reserved for electrical and mechanical operation, and relatively large temperature rise margin and relatively high safety and reliability are achieved. In the explosion-proof motor structure, first explosion-proof surfaces are respectively arranged at the joints of a base and a front end cover and a rear end cover, the length of each first explosion-proof surface is greater than 25mm, and an explosion-proof gap is not greater than 0.2 mm; a second explosion-proof surface is arranged at the joint of the machine base and the junction box base, the length of the second explosion-proof surface is greater than 12.5 mm, and the explosion-proof gap is not greater than 0.12 mm; an L-shaped explosion-proof surface and an O-shaped sealing ring are arranged at the joint of the junction box seat and the junction box cover; a third explosion-proof surface is arranged at the joint of the rotating shaft and the bearing inner cover; an end surface oil seal is arranged at the joint of the rotating shaft and the bearing outer cover; the internal net volume of the base and the internal net volume of the junction box are both larger than 2000 cm < 3 >.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to an explosion-proof motor structure. Background Art

[0002] Compared with ordinary motors, the biggest feature of explosion-proof motors is that isolation surfaces are set between the joints of the junction box, base, end cover, junction box bottom and cover, etc., so explosion-proof motors have higher requirements for sealing.

[0003] In order to improve the sealing performance of explosion-proof motors, not only the matching area is increased, but also the matching precision between various components is increased. In the design of these parts with increased matching area, a series of sealing measures such as adding rubber sealing pads, O-rings and applying sealants are adopted.

[0004] When sealing explosion-proof motors, the most important thing is to strictly seal and isolate the junction box of the explosion-proof motor from the inside of the casing. This can not only meet the dust isolation requirements of explosion-proof motors, but also meet the waterproof standards. Explosion-proof motors have high requirements for internal materials. When designing explosion-proof motors, the junction box, end cover and base must be made of high-strength materials to ensure the stability of the internal structure of the explosion-proof motor and avoid excessive internal pressure in the motor due to unqualified parts and components, which may cause explosions and burst the casing of the explosion-proof motor. When selecting materials for explosion-proof motor parts, not only must the quality of the materials be strictly controlled, but the selected parts must also be subjected to pressure resistance tests. Only after passing the test can these parts be assembled into the explosion-proof motor.

[0005] Explosion-proof motors are often used in hazardous environments, such as areas with explosion hazards (e.g., chemical plants, oil fields, mines, etc.). These motors must be specially designed and manufactured to ensure safe operation in hazardous environments. In hazardous environments, motors may be exposed to extreme high or low temperatures; improper insulation or heat dissipation system problems may cause motor overheating or insufficient cooling; and in some industrial environments, dust and particulate matter may enter the motor and affect its operation.

[0006] In addition, the failure of the junction box to seal properly causes the discharge sparks generated in the junction box to come into contact with the flammable and explosive dust outside, leading to accidents, which is also a major factor in explosion-proof motor failure. The traditional seal at the shaft penetration adopts a labyrinth loop structure, using a labyrinth ring and an end cover to form a tortuous passage to prevent dust from entering the motor. However, this structure is difficult to process and requires high assembly precision. Especially for small motors without axial positioning, the axial clearance is difficult to ensure, which easily leads to friction failures between the labyrinth ring and the end cover. Therefore, it has certain limitations. Utility Model Content

[0007] The purpose of the utility model is to provide an explosion-proof motor structure, which can reach the IP56 protection level, and does not generate sparks, arcs or dangerous temperatures that are sufficient to cause explosion hazards in the motor junction box; at the same time, it leaves a large margin for electrical and mechanical functions, has a large temperature rise margin and high safety reliability.

[0008] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0009] An explosion-proof motor structure, comprising: a rotating shaft, an end face oil seal, a bearing inner cover, a junction box cover, a junction box seat, a machine base, a rear end cover, a bearing outer cover, and a front end cover;

[0010] The connection between the base and the front cover and the rear cover is respectively provided with a first explosion-proof surface, and the length of the first explosion-proof surface is greater than 25 mm, and the explosion-proof gap is not greater than 0.2 mm;

[0011] A second explosion-proof surface is provided at the connection between the base and the junction box base, and the length of the second explosion-proof surface is greater than 12.5 mm, and the explosion-proof gap is not greater than 0.12 mm;

[0012] An L-shaped explosion-proof surface is provided at the connection between the junction box seat and the junction box cover, and an O-shaped sealing ring is also provided;

[0013] A third explosion-proof surface is provided at the connection between the rotating shaft and the bearing inner cover, and an end face oil seal is provided at the connection between the rotating shaft and the bearing outer cover;

[0014] The junction box seat and the junction cover constitute a junction box, and the internal net volumes of the seat and the junction box are both greater than 2000 cm3.

[0015] In practical application, the explosion-proof motor structure further includes: a stator core with windings, and the stator core with windings is press-fitted inside the base;

[0016] The two ends of the machine base are respectively equipped with the front end cover and the rear end cover.

[0017] The bearing inner cover and the bearing outer cover form a bearing chamber, and a ball bearing is installed in the bearing chamber.

[0018] Specifically, the rotating shaft is equipped with a fan, and the rear end cover is provided with a fan cover, and the fan cover is used to protect the fan.

[0019] Compared with the prior art, the explosion-proof motor structure described in the utility model has the following advantages:

[0020] In the explosion-proof motor structure provided by the utility model, since the first explosion-proof surface is respectively provided at the connection between the machine base and the front cover and the rear cover, and the length of the first explosion-proof surface is greater than 25mm, and the explosion-proof gap is not greater than 0.2mm, the length of the first explosion-proof surface and the gap of the first explosion-proof surface cooperate to effectively prevent the gas, dust, etc. that cause the motor explosion from entering the inside of the motor; since the second explosion-proof surface is provided at the connection between the machine base and the junction box seat, and the length of the second explosion-proof surface is greater than 12.5mm, and the explosion-proof gap is not greater than 0.12mm, the length of the second explosion-proof surface and the gap of the second explosion-proof surface cooperate to effectively prevent the arc and spark generated during the operation of the motor from igniting the flammable and explosive gas exposed in the air. body, dust; since an L-shaped explosion-proof surface and an O-ring are arranged at the connection between the terminal box seat and the terminal box cover, the explosion-proof purpose can be achieved while effectively improving the motor protection level; since a third explosion-proof surface is arranged at the connection between the rotating shaft and the bearing inner cover, and an end face oil seal is arranged at the connection between the rotating shaft and the bearing outer cover, the dynamic seal at the motor rotating shaft is effectively improved while achieving the explosion-proof purpose at the motor connection; since the terminal box seat and the terminal cover constitute the terminal box, the internal net volume of the base and the terminal box is greater than 2000cm3, so the density of explosive substances inside the motor during use can be effectively reduced, thereby effectively achieving the purpose of explosion-proof, and then reaching the IP56 protection level. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic structural diagram of an explosion-proof motor structure provided in an embodiment of the utility model.

[0022] Reference numerals:

[0023] 1-shaft; 2-end oil seal; 4-bearing inner cover; 5-junction box cover; 6-junction box seat; 7-machine base; 8-stator core with winding; 9-fan cover; 10-rear end cover; 11-bearing outer cover; 12-fan; 13-ball bearing; 14-front end cover; 151-first explosion-proof surface; 152-second explosion-proof surface; 153-third explosion-proof surface. DETAILED DESCRIPTION

[0024] For ease of understanding, the explosion-proof motor structure provided by the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings of the specification.

[0025] The utility model embodiment provides an explosion-proof motor structure, such as Figure 1 As shown, it includes: a rotating shaft 1, an end face oil seal 2, a bearing inner cover 4, a terminal box cover 5, a terminal box seat 6, a machine base 7, a rear end cover 10, a bearing outer cover 11, and a front end cover 14;

[0026] The first flameproof surface 151 is respectively provided at the connection between the base 7 and the front cover 14 and the rear cover 10, and the length of the first flameproof surface 151 is greater than 25 mm, and the flameproof gap is not greater than 0.2 mm;

[0027] A second flameproof surface 152 is provided at the connection between the base 7 and the junction box base 6, and the length of the second flameproof surface 152 is greater than 12.5 mm, and the flameproof gap is not greater than 0.12 mm;

[0028] An L-shaped explosion-proof surface is provided at the connection between the junction box seat 6 and the junction box cover 5, and an O-shaped sealing ring is also provided;

[0029] A third flameproof surface 153 is provided at the connection between the rotating shaft 1 and the bearing inner cover 4, and an end face oil seal 2 is provided at the connection between the rotating shaft 1 and the bearing outer cover 11;

[0030] The junction box seat 6 and the junction cover 5 constitute a junction box, and the internal net volume of the base 7 and the junction box is greater than 2000 cm3.

[0031] Compared with the prior art, the explosion-proof motor structure described in the embodiment of the utility model has the following advantages:

[0032] In the explosion-proof motor structure provided by the embodiment of the utility model, since the first explosion-proof surface 151 is respectively provided at the connection between the base 7 and the front cover 14 and the rear cover 10, and the length of the first explosion-proof surface 151 is greater than 25mm, and the explosion-proof gap is not greater than 0.2mm, the length of the first explosion-proof surface 151 and the gap of the first explosion-proof surface 151 are matched, so that the gas, dust and the like that cause the motor explosion can be effectively prevented from entering the inside of the motor; since the second explosion-proof surface 152 is provided at the connection between the base 7 and the junction box seat 6, and the length of the second explosion-proof surface 152 is greater than 12.5mm, and the explosion-proof gap is not greater than 0.12mm, the length of the second explosion-proof surface 152 and the gap of the second explosion-proof surface are matched, so that the arc and spark generated during the operation of the motor can be effectively prevented from igniting and being exposed in the air Inflammable and explosive gases and dust in the air; since an L-shaped explosion-proof surface is provided at the connection between the terminal box seat 6 and the terminal box cover 5, and an O-ring is provided at the same time, the explosion-proof purpose can be achieved while effectively improving the motor protection level; since a third explosion-proof surface 153 is provided at the connection between the rotating shaft 1 and the bearing inner cover 4, and an end face oil seal 2 is provided at the connection between the rotating shaft 1 and the bearing outer cover 11, the dynamic seal at the motor shaft is effectively improved while the explosion-proof purpose at the motor connection can be achieved; since the terminal box seat 6 and the terminal cover 5 constitute a terminal box, the internal net volume of the base 7 and the terminal box is greater than 2000cm3, so the density of explosive substances inside the motor during use can be effectively reduced, thereby effectively achieving the purpose of explosion-proof, and then reaching the IP56 protection level.

[0033] It should be noted that in order to prevent arcing when the motor is powered on, the internal structure of the motor junction box is designed to increase the creepage distance and the electrical clearance between electrical components.

[0034] In practical application, such as Figure 1 As shown, the explosion-proof motor structure provided by the embodiment of the utility model may also include: a winding stator core 8, and the winding stator core 8 is pressed into the inside of the base 7; the two ends of the base 7 may be respectively equipped with a front cover 14 and a rear cover 10.

[0035] Among them, Figure 1 As shown, the bearing inner cover 4 and the bearing outer cover 11 can form a bearing chamber, and a ball bearing 13 can be installed in the bearing chamber.

[0036] Specifically, Figure 1 As shown, the rotating shaft 1 may be equipped with a fan 12 , and the rear end cover 10 may be provided with a fan cover 9 , and the fan cover 9 may be used to protect the fan 12 .

[0037] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. An explosion-proof motor structure, characterized in that: include: Rotating shaft, end face oil seal, bearing inner cover, junction box cover, junction box seat, machine base, rear end cover, bearing outer cover, front end cover; The connection between the base and the front cover and the rear cover is respectively provided with a first explosion-proof surface, and the length of the first explosion-proof surface is greater than 25 mm, and the explosion-proof gap is not greater than 0.2 mm; A second explosion-proof surface is provided at the connection between the base and the junction box base, and the length of the second explosion-proof surface is greater than 12.5 mm, and the explosion-proof gap is not greater than 0.12 mm; An L-shaped explosion-proof surface is provided at the connection between the junction box seat and the junction box cover, and an O-shaped sealing ring is also provided; A third explosion-proof surface is provided at the connection between the rotating shaft and the bearing inner cover, and an end face oil seal is provided at the connection between the rotating shaft and the bearing outer cover; The junction box seat and the junction box cover constitute a junction box, and the internal net volume of the seat and the junction box is greater than 2000cm 3 .

2. The explosion-proof motor structure according to claim 1, characterized in that: Also includes: A winding stator core is provided, and the winding stator core is press-fitted inside the base; The two ends of the machine base are respectively equipped with the front end cover and the rear end cover.

3. The explosion-proof motor structure according to claim 2, characterized in that: The bearing inner cover and the bearing outer cover form a bearing chamber, and a ball bearing is installed in the bearing chamber.

4. The explosion-proof motor structure according to claim 3, characterized in that: The rotating shaft is equipped with a fan, and the rear end cover is provided with a fan cover, and the fan cover is used to protect the fan.

Images