electric machine

Abstract

The application provides a motor, comprising: a stator core, a machine shell integrally injection molded on the stator core, a first end of the machine shell having a containing cavity, a wire clamp, a power cord and a conductor being partially injection molded in the machine shell, the wire clamp being configured with a wire hole for leading out the power cord, a circuit board being arranged in the containing cavity, the power cord being electrically connected with the circuit board, a first end of the conductor being in the containing cavity and electrically connected with the circuit board, and a second end of the conductor being electrically connected with a stator winding. According to the application, the stator core, part of the wire clamp and part of the power cord are integrally injection molded to form a plastic encapsulated stator assembly, so that the periphery of the wire clamp is wrapped by BMC to form a sealed structure, thereby ensuring the sealing and waterproof of the wire outlet of the motor. Meanwhile, the circuit board is not injection molded in the machine shell but is installed in the containing cavity reserved in the machine shell, thereby solving the problem that the circuit board and the power cord are injection molded in the machine shell together, and the injection molding process is easy to cause irreparable damage to the circuit board, resulting in a high production failure rate.

Description

Technical Field

[0001] This invention belongs to the field of drive device technology, and specifically relates to an electric motor. Background Technology

[0002] Traditional encapsulated DC motors with integrated PCB assemblies, also known as built-in drive DC motors, typically have two structures: 1. The PCB assembly and power cable assembly are soldered to the outside of the injection-molded stator assembly. The power cable is led out from the stator's outlet via a cable clamp and then secured with an end cap. The drawback of this structure is that the outlet is not well-waterproofed, leading to a high failure rate when the motor is used in environments with high waterproofing requirements. Manufacturers usually perform secondary waterproofing treatment at the outlet, such as applying silicone sealant, to compensate for this structural defect. However, such sealants generally do not cure quickly and require air drying, which undoubtedly increases production difficulty and cycle time, and also hinders on-site management. 2. The PCB assembly and power cable assembly are fixed to the motor and integrated into the injection-molded stator assembly using a BMC (Body Molding Machine). This structure solves the waterproofing problem better, but due to the large number of components on the PCB assembly, irreparable damage is easily caused during high-temperature, high-pressure injection molding, resulting in a high defect rate. Summary of the Invention

[0003] Therefore, the present invention provides a motor that overcomes the shortcomings of existing plastic-encapsulated DC motors, which have poor waterproof performance because the PCB board assembly and power cord assembly are all welded to the outside of the injection-molded stator assembly. In contrast, the PCB board assembly and power cord assembly are integrally encapsulated inside the injection-molded stator assembly, which solves the waterproof problem but has a high defect rate.

[0004] To address the aforementioned problems, the present invention provides an electric motor comprising a stator core on which a stator winding is wound, an integrally molded housing on the outer side of the stator core, a receiving cavity at a first end of the housing, and further comprising a wire clip, a circuit board, a power line, and a conductor, wherein the wire clip, the power line, and the conductor are respectively partially molded within the housing, the wire clip having a wire outlet hole leading to the outside of the housing, the power line being led out through the wire outlet hole, the circuit board being disposed within the receiving cavity, one end of the power line within the housing being electrically connected to the circuit board, the first end of the conductor being within the receiving cavity and electrically connected to the circuit board, and the second end of the conductor being electrically connected to the stator winding.

[0005] In some embodiments, the cable outlet clamp is formed by splicing a first part and a second part, and the splicing of the first part and the second part forms the cable outlet hole.

[0006] In some embodiments, a power cord connector is also included, which is also partially injection molded into the housing. The first end of the power cord connector is located in the receiving cavity and electrically connected to the circuit board, and the second end of the power cord connector is electrically connected to the power cord.

[0007] In some embodiments, the circuit board is provided with a first pad hole, and the first end of the power cord connector is soldered into the first pad hole.

[0008] In some embodiments, the circuit board is further provided with a second pad hole, and the first end of the conductor is soldered into the second pad hole.

[0009] In some embodiments, a front cover is also included, which is integrally injection molded to the second end of the housing.

[0010] In some embodiments, a rear end cover is also included, wherein the housing has an integrally formed frustum, the frustum being close to a first end of the housing, the rear end cover being detachably connected to the first end of the housing, and the receiving cavity being formed between the rear end cover and the frustum.

[0011] In some embodiments, a rear end cover and a protective cover are also included. The rear end cover is integrally injection molded into the housing and is located near a first end of the housing. The protective cover is fitted to the first end of the housing, and the receiving cavity is formed between the protective cover and the rear end cover.

[0012] This invention provides a motor in which the stator core, part of the lead-out clamps, and part of the power lines are integrally injection molded using BMC to form a plastic-encapsulated stator assembly. This creates a sealed structure where the lead-out clamps are surrounded by BMC, ensuring a waterproof seal at the motor's lead-out points. Simultaneously, the circuit board is not injection molded into the housing but is installed within a pre-reserved cavity in the housing. This solves the problem of high defect rates caused by the high-temperature, high-pressure injection molding process, which easily leads to irreparable damage to the circuit board when the circuit board, lead-out clamps, and power lines are all injection molded into the housing. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the motor housing without a circuit board installed according to the first embodiment of the present invention;

[0014] Figure 2 This is a schematic diagram of the structure of a motor with a circuit board installed inside the motor housing according to the first embodiment of the present invention;

[0015] Figure 3 This is a schematic diagram of the structure of a motor housing with a rear end cover installed according to the first embodiment of the present invention;

[0016] Figure 4This is a schematic diagram of the motor housing without a circuit board installed in the second embodiment of the present invention.

[0017] Figure 5 This is a schematic diagram of the structure of a motor with a circuit board installed inside the motor housing according to the second embodiment of the present invention;

[0018] Figure 6 This is a schematic diagram of a motor housing with a protective cover installed according to a second embodiment of the present invention.

[0019] The reference numerals in the attached figures are as follows:

[0020] 1. Housing; 2. Cable clamp; 3. Circuit board; 4. Power cord; 5. Receiving cavity; 6. Power cord connector; 7. Conductor; 8. Front cover; 9. Rear cover; 10. Rotor assembly; 11. Protective cover. Detailed Implementation

[0021] See also Figures 1 to 6 As shown, according to an embodiment of the present invention, a motor is provided, comprising: a stator core on which a stator winding is wound, characterized in that a housing 1 is integrally injection molded on the outer side of the stator core, a receiving cavity 5 is integrally formed at the first end of the housing 1, and further comprising a wire clamp 2, a circuit board 3, a power line 4, and a conductor 7. The wire clamp 2, the power line 4, and the conductor 7 are respectively partially injection molded inside the housing 1. The wire clamp 2 is constructed with a wire outlet hole leading to the outside of the housing 1, and the power line 4 is led out through the wire outlet hole. The circuit board 3 is disposed in the receiving cavity 5, and one end of the power line 4 inside the housing 1 is electrically connected to the circuit board 3. The first end of the conductor 7 is located in the receiving cavity 5 and is electrically connected to the circuit board 3, and the second end of the conductor 7 is electrically connected to the stator winding. In this technical solution, by integrally injection molding the stator core, part of the wire clamp 2, and part of the power line 4 with BMC to form a plastic-encapsulated stator assembly, the wire clamp 2 is surrounded by BMC to form a sealed structure, thereby ensuring that the wire outlet of the motor is sealed and waterproof. The cable outlet clamp 2 is located at the motor's cable outlet on the housing 1. Meanwhile, the circuit board 3 is not injection molded inside the housing 1, but is installed within a pre-reserved cavity 5 in the housing 1. This solves the problem that injection molding the circuit board 3, cable outlet clamp 2, and power cord 4 together into the housing 1 under high temperature and pressure could easily cause irreparable damage to the circuit board 3, resulting in a high defect rate.

[0022] Specifically, the cable exit clamp 2 is composed of a first part and a second part, which together form the cable exit hole. The cable exit clamp 2 is not a single piece, but rather composed of two parts, either top and bottom or left and right. The first part has a first cable exit groove, and the second part has a second cable exit groove. When the first and second parts are joined, the first and second cable exit grooves combine to form a complete cable exit hole. The split structure of the cable exit clamp 2 facilitates the threading and exiting of the power cord 4. Furthermore, the cable exit clamp 2 can be made of nylon 66 material, which has a certain degree of deformation under stress. Because the actual injection molding process compresses the cable exit clamp 2, the cable exit hole formed by the combination of the first and second cable exit grooves becomes smaller. Since the insulation sheath of the power cord 4 is made of a soft material, this fills the gap between the original power cord 4 and the cable exit hole, achieving a better waterproof effect.

[0023] See also Figure 1 and Figure 4 As shown, it also includes a power cord connector 6, which is partially injection-molded into the housing 1. The first end of the power cord connector 6 is located within the receiving cavity 5 and electrically connected to the circuit board 3, while the second end is electrically connected to the power cord 4. The power cord connector 6 makes the electrical connection between the power cord 4 and the circuit board 3 more convenient. Furthermore, the fact that the power cord connector 6 is partially injection-molded into the housing 1 eliminates the need for separate fixing of the power cord connector 6, making the overall structure of the motor more stable.

[0024] In one specific implementation, the circuit board 3 is provided with a first pad hole, and the first end of the power cord connector 6 is soldered into the first pad hole, so that the connection between the power cord connector 6 and the circuit board 3 is more secure.

[0025] In this embodiment, conductor 7 is a winding connector, and the circuit board 3 is also provided with a second pad hole. The first end of the winding connector is welded into the second pad hole, making the connection between the winding connector and the circuit board 3 more secure.

[0026] See also Figure 1 As shown, the motor also includes a front cover 8 and a rear cover 9. In a first embodiment, the front cover 8 is integrally injection molded to the second end of the housing 1, resulting in higher structural strength of the motor and better coaxiality between the front cover 8 and the housing 1. The housing 1 has an integrally formed frustum, which is close to the first end of the housing 1. The rear cover 9 is detachably connected to the first end of the housing 1, and a receiving cavity 5 is formed between the rear cover 9 and the frustum.

[0027] See also Figures 4 to 6As shown, the motor also includes a protective cover 11. In a second embodiment, the rear end cover 9 is integrally injection molded into the housing 1, and the rear end cover 9 is located near the first end of the housing 1. The protective cover 12 is fitted onto the first end of the housing 1, forming a receiving cavity 5 between the protective cover 12 and the rear end cover 9. The integral injection molding of the rear end cover 9 and the housing 1 results in a motor with higher structural strength and better coaxiality between the rear end cover 9 and the housing 1. The protective cover 12 is used to protect the circuit board 3.

[0028] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0029] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. An electric motor, comprising a stator core on which stator windings are wound, characterized in that, The stator core has an integrally molded housing (1) on its outer side. The first end of the housing (1) has a receiving cavity (5) and also includes a wire clip (2), a circuit board (3), a power cord (4), and a conductor (7). The wire clip (2), the power cord (4), and the conductor (7) are partially injection molded inside the housing (1). The wire clip (2) has a wire outlet hole leading to the outside of the housing (1). The power cord (4) is led out through the wire outlet hole. The circuit board (3) is located inside the receiving cavity (5). The power cord (4) is located inside the housing (1). One end is electrically connected to the circuit board (3), the first end of the conductor (7) is located in the receiving cavity (5) and electrically connected to the circuit board (3), and the second end of the conductor (7) is electrically connected to the stator winding; it also includes a rear end cover (9) and a protective cover (11), the rear end cover (9) is integrally injection molded in the housing (1), and the rear end cover (9) is close to the first end of the housing (1), the protective cover (12) is assembled at the first end of the housing (1), and the receiving cavity (5) is formed between the protective cover (12) and the rear end cover (9).

2. The motor according to claim 1, characterized in that, The cable outlet clamp (2) is formed by splicing a first part and a second part, and the splicing of the first part and the second part forms the cable outlet hole.

3. The motor according to claim 1, characterized in that, It also includes a power cord connector (6), which is also partially injection molded inside the housing (1). The first end of the power cord connector (6) is located inside the receiving cavity (5) and electrically connected to the circuit board (3). The second end of the power cord connector (6) is electrically connected to the power cord (4).

4. The motor according to claim 3, characterized in that, The circuit board (3) is provided with a first pad hole, and the first end of the power line connector (6) is soldered into the first pad hole.

5. The motor according to claim 1, characterized in that, The circuit board (3) is also provided with a second pad hole, and the first end of the conductor (7) is soldered into the second pad hole.

6. The motor according to claim 1, characterized in that, It also includes a front cover (8), which is integrally injection molded to the second end of the housing (1).

7. The motor according to claim 1, characterized in that, It also includes a rear end cover (9), and the housing (1) has an integrally formed frustum. The frustum is close to the first end of the housing (1). The rear end cover (9) is detachably connected to the first end of the housing (1). The receiving cavity (5) is formed between the rear end cover (9) and the frustum.

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