BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a motor stator and, more particularly, to a motor stator having an electrical connection module penetrating a plurality of wiring layers to lower complexity in circuit arrangement.
2. Description of the Related Art
In the current trend of miniaturization for electrical devices, cooling fans disposed inside miniaturized electrical devices to drive air currents for cooling have to be smaller than conventional fans. Furthermore, in the design and manufacture of a miniaturized fan, the way to form a motor with great power and strong structure has become a critical factor in fan miniaturization. In detail, there are motor stators with its stator coils formed on a circuit board by PCB layout or electroforming, since conventional motor stators formed by conventional winding coils are hard to fill light and thin requirements. Besides, in order to provide a large transient power for motor operation, a multi-layer-board with coil circuits arranged on each layer to perform a motor stator has also been used. For example, a motor stator completed by plural layers with coil circuits is disclosed by an invention of Taiwan Patent Publication No. 201123686, which is entitled as “Winding Device with Axial Flux and a Motor Having the Winding Device,” with the motor stator being numbered as “9” in FIG. 1. The motor stator 9 includes a flexible base 91 and a wiring module 92, wherein the flexible base 91 has a plurality of carriers 911 and a plurality of bridge portions 912, each of the carriers 911 supports a coil unit 921 of the wiring module 92, and each of the bridge portions 912 supports a connecting circuit 922 of the wiring module 92. Particularly, any one of the bridge portions 912 is connected between adjacent two of the carriers 911, and the connecting circuit 922 on the bridge portion 912 electrically links the coil units 921 on the two carriers 911. Moreover, the bridge portions 912 of the flexible base 91 are bent for the carriers 911 to align with each other in an axial direction of a rotor and the plurality of carriers 911 are arranged adjacent to the rotor when this motor stator and the rotor are assembled. Therefore, the coil units 921 generate magnet force to drive the rotor when the coil units 921 are energized.
However, this conventional motor stator has drawbacks such as low structural strength and low combination stability since the flexible base 91 is formed by flexible material. Besides, any bridge portion 912 connecting between two of the carriers 911 will be bent to a state having a small curvature once it is necessary to decrease the axial thickness of this motor stator, and this may cause damages to the bridge portion 912. Moreover, when the motor stator is assembled in a motor, with the bridge portions 912 bent and the carriers 911 aligned in a line, the bridge portions 912 protruding from radial peripheries of the carriers 911 may radially result in additional area for receiving the conventional motor stator. Furthermore, a circuit layout of the wiring module 92 should be complex since the wiring module 92 can be formed on only two opposite surfaces of the flexible base 91, and this complexity in circuit layout can lead to a low yield rate of the motor stator. Consequently, it is desired to improve the conventional motor stator.
SUMMARY OF THE INVENTION
It is therefore the primary objective of this invention to provide a motor stator having an electrical connection module electrically connecting winding modules of a plurality of wiring layers, so as to has decreased arranging space, desirable structural strength and combination stability, and low complexity in circuit layout.
The invention discloses a motor stator comprising a plurality of wiring layers and at least one electrical connection module. Each electrical connection module has a thorough conductor and at least one local conductor, with the thorough conductor penetrating the plurality of wiring layers and electrically connecting with at least one of the at least one winding module of at least one of the plural wiring layers, with the at least one local conductor penetrating at least one of the plural wiring layers, and with each local conductor electrically connecting the winding modules of at least two of the plural wiring layers.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a perspective view of a conventional motor stator completed by plural layers.
FIG. 2 is an exploded and perspective view of a motor stator according to a first practical example of a preferable embodiment of the invention.
FIG. 3 is a sketch and cross-sectional view of the motor stator according to the first practical example of the preferable embodiment of the invention.
FIG. 4 is an exploded and perspective view of an alternative motor stator according to the first practical example of the preferable embodiment of the invention.
FIG. 5 is a sketch and cross-sectional view of the alternative motor stator according to the first practical example of the preferable embodiment of the invention.
FIG. 6 shows a circuit diagram of the motor stator according to the first practical example with a parallel structure.
FIG. 7 shows a circuit diagram of the alternative motor stator according to the first practical example with a serial structure.
FIG. 8 is an exploded and perspective view of a motor stator according to a second practical example of the preferable embodiment of the invention.
FIG. 9 is an exploded and perspective view of an alternative motor stator according to the second practical example of the preferable embodiment of the invention.
FIG. 10 is an exploded and perspective view of a thin fan having the motor stator of the preferable embodiment of the invention.
In the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the term “first,” “second,” and similar terms are used hereinafter, it should be understood that these terms refer only to the structure shown in the drawings as it would appear to a person viewing the drawings, and are utilized only to facilitate describing the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 2-5, for illustrating a preferable embodiment of the present invention, exploded and perspective views and sketch and cross-sectional views of a first practical example are shown, which is a motor stator of a multi-layer-board structure. The motor stator includes a plurality of wiring layers 1 and an electrical connection module 2 penetrating the plurality of wiring layers 1. Besides, the motor stator of the first practical example is designed to be applied to single-phase motors.
In detail, referring to FIGS. 2 through 5, each of the wiring layers 1 includes an insulating base 11, a through hole 12, a conduction hole 13 and a winding module 14. The insulating base 11 has a supporting surface 111 and a bottom surface 112, which preferably form two opposite sides of the insulating base 11. The through hole 12 penetrates the insulating base 11 from the supporting surface 111 to the bottom surface 112, with the through holes 12 of all wiring layers 1 aligned with each other along an axial line and preferably having identical bores. The conduction hole 13 also penetrates the insulating base 11 from the supporting surface 111 to the bottom surface 112. The winding module 14 is arranged on the supporting surface 111 of the insulating base 11 and has a first end 141 and a second end 142, wherein the first end 141 extends to the conduction hole 13 while the second end 142 extends to the through hole 12, or the first end 141 does not extend to any one of the holes 12, 13 of this wiring layer 1 while the second end 142 extends to the conduction hole 13.
The electrical connection module 2 is preferably formed by electric conductive material, such as solder, implanted inside the through hole 12 or the conduction hole 13, with the electrical connection module 2 including a thorough conductor 21 and at least one local conductor 22. The thorough conductor 21 is disposed inside the through holes 12 of the plurality of wiring layers 1 to penetrate the plurality of wiring layers 1, and the thorough conductor 21 electrically connects with any second end 142 of the winding modules 14 that extends to any through hole 12 of the plural wiring layers 1. Each local conductor 22 is disposed inside at least one of the conduction holes 13 to penetrate at least one of the plural wiring layers 1. Besides, each local conductor 22 electrically connects with any first end 141 of the winding modules 14 that extends to one of the conduction holes 13, or electrically connects two first ends 141 of two winding modules 14, or electrically connects two second ends 142 of two winding modules 14 not in connection with any one of the local conductors 21.
In detail, referring to FIGS. 2 and 3, when the conduction holes 13 of the plurality of wiring layers 1 are aligned with each other, the number of the at least one local conductor 22 is one, the local conductor 22 electrically connects with the first ends 141 of the winding modules 14 of the plurality of wiring layer 1, and the second ends 142 of the winding modules 14 of the plurality of wiring layer 1 extend to the through holes 12 and electrically connect with the thorough conductor 21, so as to complete a parallel structure of the winding modules 14 as shown in FIG. 6 by the electrical connection module 2. On the other hand, referring to FIGS. 4 and 5, when the conduction holes 13 of the plurality of wiring layers 1 are staggered, the number of the at least one local conductor 22 is equal to that of the plural wiring layers 1, and any one of the local conductors 22 is received inside the conduction hole 13 of one of the plural wiring layers 1. Any one of the local conductors 22 electrically connects with the first end 141 of the winding module 14 extending to the conduction hole 13 receiving this local conductor 22 and another first end 141 of a winding module 14 of another wiring layer 1, or electrically connects with the second end 142 of the winding module 14 extending to the conduction hole 13 receiving this local conductor 22 and another second end 142 of a winding module 14 of another wiring layer 1. Therefore, when the thorough conductor 21 only electrically connects with the second end 142 of the winding module 14 of one of the plural wiring layers 1, a serial structure of the winding modules 14 as shown in FIG. 7 by the electrical connection module 2 is completed.
Please refer to FIG. 8, which illustrates an exploded and perspective view of a second practical example of the preferable embodiment of the present invention, and the motor stator of this second practical example is designed to be applied to multi-phase motors. In this second practical example, each wiring layer 1 has a plurality of through holes 12, a plurality of conduction holes 13 and a plurality of winding modules 14, with numbers of the plural through holes 12, conduction holes 13 and winding modules 14 being equal to or larger than the number of the phases of an applied multi-phase motor. For instance, if the motor stator of the present invention is applied to a two-phase motor as shown in FIG. 8, the number of the through holes 12 can be two, and the numbers of the conduction holes 13 and the winding modules 14 may be six. For the same reason, when the motor stator of the present invention is applied to a three-phase motor, the number of the through holes 12 of each wiring layer 1 should not be less than three. It should be noted that a connection between the winding modules 14 and the electrical connection module 2 for one phase current to pass through is similar to the connection of the first practical example.
Moreover, referring to FIG. 8 again, regarding to a thorough conductor 21 and a local conductor 22 that are arranged for a single phase current to pass through, it is preferable to arrange the thorough conductor 21 and the local conductor 22 respectively on the inside and the outside of a coil of the winding module 14 for convenience of connection between the winding module 14 and the electrical connection module 2. Namely, the thorough conductor 21 is on one of the inside and the outside of the coil while the local conductor 22 is on the other one of them of the coil. Alternatively, referring to FIG. 9, regarding the thorough conductor 21 and local conductor 22 for a single phase current to pass through, both of the thorough conductor 21 and the local conductor 22 can be arranged outside the coil of the winding module 14 or inside the coil of the winding module 14.
Referring to FIG. 10, an exploded and perspective view of a thin fan having the motor stator of the present invention is shown. The motor stator is mounted on a base seat 3 of the thin fan while the thin fan further provides a fan wheel 4 having a magnet surface 41 facing the motor stator, so as to rotate the fan wheel 4 when the winding modules 14 of the motor stator is energized.
In sum, with the electrical connection module 2 penetrating the plurality of wiring layer 1, the winding modules 14 can be electrically connected by the electrical connection module 2. Therefore, not only can the above structure prevent the electrical connection module 2 from damage caused by external force to maintain the normal operation of the motor stator, but it can also further decrease the required space for the motor stator. Moreover, the present invention can have desirable structural strength and combination stability since the insulating base 11 of the wiring layer 1 can be formed by a rigid board. Besides, the circuit layout of the present motor stator can be simple because each local conductor 22 penetrates at least one of the plural wiring layers 1 to electrically connect the winding modules 14 that are respectively formed on supporting surfaces 111 of different wiring layers 1, and thus may lead to a high yield rate of the motor stator.
Although the invention has been described in detail with reference to its presently preferable embodiment, it will be understood by one of ordinary skill in the art that various modifications can be made without departing from the spirit and the scope of the invention, as set forth in the appended claims.
Patent Application
20130049500
