JP4200281B2 - Molded motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ground structure for a molded motor.
[0002]
[Prior art]
Since the stator of the mold motor is covered with the mold resin, it is difficult to connect the stator core to the ground, and there is a problem that the electric charge accumulated in the stator core is discharged through the bearing and damages the bearing.
[0003]
Therefore, in a conventional molded motor, a structure in which a stator core is cut from a mold jacket and a ground screw is provided (see, for example, Patent Document 1), a fixing pin is fitted to the stator core, and the fixing pin is attached. A structure in which the fixing pin is exposed to the outside of the insulating material via an insulating substrate, and a screw provided on a metal bracket is pressed against the fixing pin to connect to the outside (for example, Patent Document 2) Have been proposed).
[0004]
[Patent Document 1]
JP-A-7-298543 [Patent Document 2]
JP-A-8-223845
[Problems to be solved by the invention]
However, when the conventional grounding structure is used for a small motor, when the screw is machined from the mold jacket, the stator iron core is small, and there is a risk of damaging the winding by penetrating the stator iron core.
[0006]
Further, in the structure in which the fixing pin is fitted to the stator core and connected to the ground wire via the insulating substrate, it is difficult to secure a space for fitting the fixing pin to the outer peripheral end surface of the stator core.
[0007]
Further, in the structure in which the screw is pressed against the fixing pin, a gap is formed between the screw and the fixing pin due to heat shrinkage of the resin, and it is difficult to permanently connect the ground.
[0008]
The present invention solves the above-described conventional problems, and an object of the present invention is to provide a highly reliable molded motor that can be securely and easily grounded to a stator core.
[0009]
[Means for Solving the Problems]
In order to solve the above-described conventional problems, the present invention protects the output end of the ground terminal from an insulator that insulates the stator core and the stator winding, a ground terminal that is mounted on the insulator, and a mold resin. An insulating cap; and the ground terminal is electrically coupled to an output end portion that is exposed to the outside of the mold and used for connection to a ground wire, a fitting portion that is press-fitted to the insulator, and a stator core The ground end is electrically conductively fixed to the outer periphery of the stator core by welding, and the output end is fixed to the stator core in a state where the terminal insertion hole of the insulating cap is fitted. child winding by resin molding, the output end which was exposed to mold the outside, the molded motor having a highly reliable grounding structure is obtained, a charge accumulated in the stator core Leads to external ground through the scan terminal, it is possible to prevent the bearing from being damaged by discharge.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In order to solve the above-mentioned problem, the molded motor according to claim 1 is an insulator that insulates the stator core from the stator winding in a motor in which the stator core and the stator winding are integrally molded with a mold resin. And an insulating cap that protects the output end of the ground terminal from the mold resin, and the ground terminal is exposed to the outside of the mold and used for connection to the ground wire. An output end, a fitting portion that is press-fitted to the insulator, and a ground end that is electrically coupled to the stator core, and the ground end is conductively fixed to the outer periphery of the stator core by welding; said stator core in a state where the fitting the terminal insertion hole of the insulating cap and the stator winding by resin molding on the output end, even the output end exposed to mold the outside In, by attaching fixing the advance ground terminal to the insulator, is determined to ensure the position of the output end and the ground end of the ground terminal. Further, the welding operation can be facilitated, and the welding resin can withstand the flow pressure of the mold resin, and the connection can be reliably ensured even after molding. With this ground terminal, the charge of the stator core can be guided to the external ground.
[0011]
Further, in addition to the above, the molded motor according to claim 2 is provided with a concave portion on the outer periphery of the stator core, and this concave portion is used as a welded portion, which can be protected from external force and has a large outer diameter. Can be prevented.
[0012]
Furthermore, the molded motor according to claim 3 is provided with at least a metal bracket at one end of the molded stator, and the ground terminal and the bracket are electrically connected. can get.
[0013]
【Example】
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0014]
In FIG. 1, 1 is a stator core, 2 is a stator winding, 3 is an insulator, 4 is a ground terminal, 5 is an insulation cap, 6 is a mold resin, and the stator core 1 and the stator winding 2 are molded. The outer cover is formed, and the anti-load side bearing housing is also integrally formed. Reference numeral 7 denotes an aluminum bracket having a load side bearing housing and a mounting flange. Reference numeral 8 denotes a rotor, which is integrally provided with a shaft 9. 10 is a ball bearing, 11 is an aluminum cover, and 12 is a screw.
[0015]
First, the insulator 3 is attached to both ends of the stator core 1 and insulated, and then the stator winding 2 is wound. Thereafter, the ground terminal 4 is press-fitted to the insulator 3.
[0016]
This ground terminal 4 is electrically coupled to the stator core 1 by welding to an output end 4a that is exposed to the outside of the mold and used for connection to a ground wire, a fitting portion 4b that is press-fitted to the insulator 3, and a stator core 1. And an earth end 4c (FIG. 2).
[0017]
Then, the ground terminal 4 is covered with an insulating cap 5, and the stator core 1 and the stator winding 2 are resin-molded.
[0018]
The insulating cap 5 protects the output end 4a of the ground terminal 4 from the mold resin 6 at the time of molding, and has a terminal insertion hole having an appropriate squeeze with the output end 4a. Even if resin molding is performed, the terminal portion 4a can be exposed to the outside.
[0019]
By connecting a lead wire to the exposed output end 4a and connecting to an external ground, the electric charge accumulated in the stator core 1 can be released to the external ground.
[0020]
Only the connection of the lead wire for grounding may be used, but in order to secure grounding, the output end 4a of the grounding terminal 4 and the cover 11 are electrically connected.
[0021]
Then, ball bearings 10 are mounted on both sides of the shaft 9 of the rotor 8 and are rotatably supported by the molded stator and the housing of the bracket 7. Finally, the bracket 7 and the cover 11 are fastened with screws 12 to complete the molded motor.
[0022]
By fastening the screw 12, the ground terminal 4 connected to the stator core 1, the cover 11, and the bracket 7 are electrically connected. In other words, the stator core 1 and the load-side bearing 10 fixed to the bracket 7 have the same potential, the current flowing through the bearing 10 can be further reduced, and the risk of damage to the bearing can be reduced. High mold motor can be configured.
[0023]
Note that the ground terminal 4 may be provided on the bracket 7 side. In this case, the cover 11 may be omitted.
[0024]
FIG. 3 is a perspective view showing mounting of the ground terminal and the insulator and a welded portion of the ground terminal and the stator core.
[0025]
The insulator 3 has an insertion hole (not shown) into which the fitting portion 4 b of the ground terminal 4 is inserted in the axial direction, and is fixed in accordance with the slot of the stator core 1. For this reason, the position of the ground terminal 4 attached to the insulator 3 with the stator core 1 is constant.
[0026]
Moreover, since the recessed part (groove) was provided in the outer periphery of the stator core 1, it can protect that an external force is hard to apply to a welding location. Further, the outer periphery of the stator core 1 is easily contaminated before the winding process, and the welding strength is stabilized because the stator core 1 is welded to the fracture surface of the recess. Furthermore, it is possible to prevent the mold outer diameter of the welded portion from increasing.
[0027]
In addition, although a recessed part is conduction-fixed by welding to the outer periphery of the earth | ground end part 4c and the stator core 1, you may use methods, such as soldering and brazing.
[0028]
In the present embodiment, the earth terminal is provided at one end of the mold resin, but it may be provided at both ends. Furthermore, if a ground terminal is provided on the non-output shaft side, the motor control circuit section can be provided integrally, and can be easily connected to the ground side of the circuit board.
[0029]
【The invention's effect】
As apparent from the above embodiment, according to the first aspect of the invention, by attaching the fitting portion of the ground terminal to the insulator, the positions of the output end and the ground end are determined, and the stator core and the ground The conduction with the terminal can be ensured, and the molding process can be facilitated.
[0030]
Further, since the fixedly welded A over scan terminals on the outer periphery of the stator core, after being molded it can be ensured a ground connection.
[0031]
Further, according to the invention described in claim 2 , it is possible to improve the reliability of the ground connection portion and to prevent the mold outer diameter from increasing.
[0032]
Furthermore, according to the invention described in claim 3 , a more reliable and reliable ground structure can be obtained.
[0033]
Therefore, it is possible to obtain a molded motor having a simple structure and a highly reliable earth structure.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a molded motor of the present invention. FIG. 2 is a perspective view showing a ground terminal of the invention. FIG. 3 is a perspective view showing a main part of the invention.
DESCRIPTION OF SYMBOLS 1 Stator core 2 Stator winding 3 Insulator 4 Ground terminal 4a Output end 4b Fitting part 4c Ground end 5 Insulation cap 6 Mold resin 7 Bracket 8 Rotor 9 Shaft 10 Ball bearing 11 Cover 12 Screw

Claims (3)

In a motor in which a stator core and a stator winding are integrally molded with a mold resin, an insulator that insulates the stator core and the stator winding, a ground terminal attached to the insulator, a mold resin from the ground terminal An insulating cap that protects the output end; the ground terminal is exposed to the outside of the mold and used for connection to a ground wire; a fitting portion that is press-fitted to the insulator; and a stator A state in which a ground end electrically coupled to the iron core is provided, the ground end is conductively fixed to the outer periphery of the stator core by welding, and a terminal insertion hole of the insulating cap is fitted to the output end A molded motor , wherein the stator core and the stator winding are resin-molded and the output end is exposed to the outside of the mold. A recess provided in the outer periphery of the stator core, the molded motor according to claim 1, wherein the concave portion has a weld point. 3. The molded motor according to claim 1, wherein at least one metal bracket is provided at one end of the molded stator, and an earth terminal and the bracket are electrically connected.

Images