KR20020029360A - Coin Type Driving Motor and Manufacturing Method of the Motor - Google Patents

Abstract

PURPOSE: A coin type vibration motor and method for manufacturing the same is provided to reduce manufacturing procedures by eliminating a plating process and the need of using a printed circuit board, while lengthening useful life of commutator. CONSTITUTION: A coin type vibration motor comprises an upper case(10); a lower case(20); a magnet(30) attached to the lower case; a rotor(40) having a coil(120) and a commutator(110); an eccentric weight(140) arranged at the outer periphery of one or two coils of the rotor from among three coils disposed at a gap angle of 120 degrees so as to increase an eccentric distance; and a magnetic ring(50) disposed onto the rotor. A method for manufacturing the coin type vibration motor comprises a first step of pressing a commutator; a second step of soldering the commutator to a flexible printed circuit board; a third step of manufacturing a rotor by integrally injecting molding the flexible printed circuit board, coil and a bearing into a single body; a fourth step of soldering a coil to the solder land of the commutator; and a fifth step of attaching the magnetic ring onto the rotor.

Description

Coin-type vibration motor and its manufacturing method {Coin Type Driving Motor and Manufacturing Method of the Motor}

The present invention relates to a vibration motor, in particular a coin-type vibration motor for generating a vibration used in one of the forms of receiving a wireless signal mounted on a mobile communication terminal such as a cellular phone (PCS Phone) or PDA and a manufacturing method thereof It is about.

Typically, a motor converts electrical energy into mechanical energy and is commonly referred to as an electric motor. The electric motor converts electrical energy into mechanical energy called torque by mediating the electromagnetic field of the gap between the stator and the rotor according to the so-called Fleming's left-hand law that a current-carrying conductor is subject to force.

Electric motor is a type that rotates the coil between N pole and S pole of electromagnet and rotates with current through coil. It has DC line synchronous and AC current magnetic synchronous, and it uses Arago's original principle and eddy current. And synchronous motors. Such electric motors have a wide range of applications depending on the type and size, and the range of their use is fairly broad. In other words, the use is different depending on the device installed on the shaft of the electric motor. Such electric motors are widely used in various electric and electromechanical devices, for example, motors for vibration of PAGERs and mobile phones, motors for blowing fans, and hydraulic or pneumatic motors.

Motors for vibration of mobile communication terminals such as mobile phones and pagers are classified into cylindrical bar type and disc type coin type.

In this conventional vibration motor, a cylindrical motor and a coin-type vibration motor coexist. Prior arts related to coin type vibration motors are well disclosed in Korean Patent Laid-Open Publication No. 2000-0044439 (published Jul. 15, 2000; coin-type drive motor), and thus the configuration of a conventional vibration device will be described. .

1 is a perspective view showing a coin-type vibration motor according to a conventional embodiment and Figure 2 is an exploded perspective view showing a coin-type vibration motor according to a conventional embodiment. 1 and 2, the vibration device mounted to the mobile phone is composed of a single vibration motor, the vibration motor is a magnet (3) and the rotor (4) in the metallic upper and lower cases (1, 2) Was installed around the shaft. That is, the lower case 2 on which the flexible circuit 6 for signal transmission is placed on the floor, the ring-shaped magnet 3 coaxially mounted on the flexible circuit 6, and a plurality of coil bundles 5 are rotated from the center of rotation. It is composed of a disk-shaped rotor that is provided symmetrically and rotates according to the electromagnetic force generated by the interaction between the magnet and the coil bundle, and the upper case 1 is pressed into the lower case to be included in the rotor.

Further, Japanese Patent Application Laid-Open No. 2001-0113560 (December 28, 2001; a rotor having a printed wiring commutator member and a flat motor having the same rotor) includes a vibration motor having a rotor for installing a commutator on a printed wiring board. The technology is disclosed.

In the conventional method of manufacturing a coin-type vibration motor, a commutator and a circuit pattern are formed on a double-sided printed wiring board by etching, and the two-sided pattern is connected by through-hole plating, and Ni plating and Au are further formed on the commutator and the circuit. Use a printed wiring board for plating. This is the method used by TOKYO PARTS of Japan and other domestic companies to manufacture vibration motors.

If the commutator is formed on the printed wiring board according to the conventional method, the manufacturing process is complicated, which increases the unit cost, and the overall thickness of the copper foil plated to about 0.025 mm is short, resulting in a short life. In addition, when the brush passes through the SLOT section of the commutator, the commutator wears severely and causes fire occurrence.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to form a flexible printed circuit board (FPCB) without forming a commutator facing a brush on the printed wiring board. The present invention provides a coin type vibration motor and a method of manufacturing the same, which make the manufacturing process simple and enable the use of a thicker commutator than the commutator of a conventional printed wiring board.

1 is a perspective view showing a coin-type vibration motor according to a conventional embodiment.

Figure 2 is an exploded perspective view showing a coin-type vibration motor according to a conventional embodiment.

3 is a view illustrating a coupling state between a commutator and an FPCB.

4 is a diagram illustrating a terminal connection state of a coil.

5 is a plan view of a rotor integrally injection molded with a coil after soldering a commutator and a FPCB.

6 is a cross-sectional view of a rotor integrally injection molded with a coil after soldering a commutator and an FPCB.

Figure 7 is an exploded perspective view showing a coin-type vibration motor according to an embodiment of the present invention.

8 is a cross-sectional view of the coin-type vibration motor according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

1, 10: upper case 2, 20: lower case

3, 30: magnet 4, 40: rotor

50: magnetic ring 60: brush

70: shaft 100: FPCB

110: commutator 120: coil

130: bearing 140: eccentric weight

150: line of sight 170: solder land (Solder Land)

Coin-type vibration motor and a method of manufacturing the same according to the present invention for achieving the above object in the conventional coin-type vibration motor manufacturing method for forming a commutator and a circuit pattern on a double-sided printed circuit board, presses the commutator (segment) separately (Press) processing; Soldering the commutator to a flexible printed circuit board (FPCB); Manufacturing a rotor by integrally injection-molding the commutator with a solder-coupled FPCB and a known coil and bearing; Solder-coupling the gaze of the coil to the solder portion of the commutator after injection molding coupling; And attaching a magnetic ring to an upper surface of the rotor.

The commutator has a thickness of 0.04 mm to 0.06 mm so as not to be easily worn, and is characterized by being plated with precious metals such as gold and silver.

In addition, the present invention is a conventional coin-type vibration motor consisting of a rotor (rotator) having a magnet and a coil and a commutator attached to the upper and lower cases and the lower case, the rotor is between 120 degrees to increase the eccentric distance It has an eccentric weight made of tungsten powder on the outer periphery of one or two coils of the three coils arranged at each angle, characterized in that it comprises a magnetic ring located on the top of the rotor.

The magnetic ring is made of 13 chromium (Cr) steel and is attached to the top of the rotor to maintain a constant gap between the rotor and the upper case by the repulsive force of the magnet attraction force and the spring force of the brush. It is done.

Hereinafter, with reference to the accompanying drawings will be described in detail the most preferred embodiment of the present invention. In the drawings, it should be noted that like elements or parts represent the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

3 is a diagram illustrating a coupling state of a commutator and an FPCB, and FIG. 4 is a diagram illustrating a terminal connection state of a coil. The commutator 110 is manufactured by pressing separately and soldered to one surface of the FPCB 100 as shown in FIG. 3, and the coil 120 of FIG. 4 is positioned on the opposite side to form the rotor 40. do. The commutator has a thickness of 0.05 mm and is made by pressing a plating process with precious metals such as gold and silver. The manufacture of the rotor is carried out through the following process.

FIG. 5 is a plan view of a rotor integrally injection-molded with a coil after soldering a commutator and an FPCB, and FIG. 6 after soldering a commutator and an FPCB. Fig. 7 is a cross-sectional view illustrating a coin-type vibration motor according to an embodiment of the present invention, and Fig. 8 is a coin type according to an embodiment of the present invention. Sectional view of the vibration motor.

As can be seen in FIG. 6, the rotor 40 is manufactured by injecting the FPCB 100, the coil 120, and the bearing 130 to which the commutator 110 is coupled into a resin and integrally molding the resin.

In particular, when the rotor 40 is manufactured, it is manufactured by forming an eccentric weight 140 made of tungsten powder, and a magnetic ring 50 is attached to an upper portion of the rotor 40.

In the vibration motor, the amount of vibration can be obtained by the eccentric principle as the center of gravity of the rotor is far from the center of the shaft, the larger the mass of the rotor and the larger the number of revolutions of the rotor. This is expressed as follows.

Vibration amount = revolutions ² × eccentricity × rotor mass

As a method for increasing the amount of vibration, the conventional slim vibration motor has a mechanical limitation, so that the rotor is usually formed by a semi-circular plate-shaped structure with coils on one side and integrally formed as a high specific gravity resin having a specific gravity of about 5 to rotate the weight of the rotor. By moving the center or by the other way, the rotor moves the center of gravity of the rotor by placing the coil on one side and the eccentric weight made of tungsten powder on the opposite side. It becomes heavier than g, so a relatively large amount of vibration can be obtained. However, there is a disadvantage in that the current consumption increases because a lot of torque (Torque) is required when driving. On the other hand, when increasing the number of revolutions can increase the amount of vibration, but there is a disadvantage that the life of the motor is shortened due to wear of the commutator.

Therefore, in the present invention, by setting the eccentric weight 140 made of tungsten powder on the outer circumference of the two coils of the three coils as described above, the eccentric distance is made larger or larger than the radius of the rotor. Therefore, as in the prior art, the number of revolutions of the rotor 40 and the mass of the rotor are increased to increase the amount of vibration by increasing the eccentric distance without increasing the amount of vibration.

In order to operate the vibration motor stably, it is necessary to maintain constant air gap between the rotor composed of coil and commutator and the magnet composed of stator. Conventional configuration for maintaining the air gap is that the rotor is in close contact with the upper housing by the spring force of the brush is to be rotated. At this time, a polyester-based friction-resistant film is mounted between the rotor and the housing to play a lubrication role. In this method, since the rotor is in close contact with the housing, the gap between the gaps can be changed by the external pressure and force of the product.

Therefore, in the present invention, the magnetic force ring 50 made of 13 chrome (Cr) steel is attached to the upper portion of the rotor 40 in a manner of maintaining a constant void at all times, and the suction force of the magnet 30 and the spring of the brush 60 are maintained. The repulsive force ensures a constant void at all times. The ring has an outer diameter of φ3.5 and the brush 60 is maintained at a height of about 0.8 mm from the top surface of the magnet 30.

In the injection-molded rotor 40, the line of sight of the coil 120 is soldered to the solder land 170 of the commutator 110.

On the other hand, the detailed description of the present invention has been described with respect to specific embodiments, it will be apparent to those skilled in the art that various modifications are possible without departing from the scope of the present invention.

As described above, according to the present invention, since the commutator is press-processed with a material which is plated with a noble metal having a thickness of 0.05 mm, the plating process is not necessary and the manufacturing process is not required because the printed wiring board is not used. It is simpler, and the thickness of the commutator is thicker than the commutator of the conventional printed wiring board having a thickness of 0.025mm, which has the advantage of extending the life of the commutator. In addition, since the SLOT section of the commutator having a thickness of 0.05 mm is formed to have sufficient space to be filled as the resin during the integral molding injection, the SLOT is filled with the resin, so that the brush has less interference when passing through the SLOT section. Less wear and less sparks. In addition, by maximizing the eccentric distance, it is possible to maximize the amount of vibration as a rotor of low weight, and there is an advantage that the life can be improved due to the small current consumption. In addition, it is possible to maintain a constant interval even during the movement of the process, so there is no fear that the rotor will drop out due to the impact, and it is possible to determine the abnormality of the product without covering the housing even during the rotation inspection during the process, thereby simplifying the work process. The advantage is that savings are possible.

Claims (5)

A conventional coin-type vibration motor manufacturing method for forming a commutator and a circuit pattern on a double-sided printed wiring board, the method comprising: separately pressing a commutator (Segment); Soldering the commutator to a flexible printed circuit board (FPCB); Manufacturing a rotor by integrally injection-molding the commutator with a solder-coupled FPCB and a known coil and bearing; Solder-coupling the gaze of the coil to the solder portion of the commutator after injection molding coupling; Method of manufacturing a coin-type vibration motor comprising attaching a magnetic ring to the upper surface of the rotor. The method of claim 1, wherein the commutator has a thickness of 0.04 mm to 0.06 mm so as not to be easily worn, and is coated with a noble metal such as gold and silver. In the conventional coin-type vibration motor consisting of a rotor (rotator) having a magnet, a coil and a commutator attached to the upper and lower cases and the lower case, The rotor has an eccentric weight on the outer periphery of one or two coils of three coils arranged at an angle between 120 degrees to increase the eccentric distance, Coin-type vibration motor, characterized in that comprising a magnetic ring located on the top of the rotor. 4. The upper part of the rotor according to claim 3, wherein the magnetic ring is made of 13 chromium (Cr) steel to maintain a constant gap between the rotor and the upper case by the repulsive force of the magnet attraction force and the spring force of the brush. Coin-type vibration motor, characterized in that attached to. The coin type vibration motor according to claim 3, wherein the eccentric weight is made of tungsten powder.