JPH04271244A - Motor with terminal - Google Patents

Abstract

PURPOSE:To directly connect an external side end part of a terminal pin to a connection part of a circuit board by holding a drive coil by a bobbin part, extending the bobbin part to a predetermined position in a mounting surface of a motor to form a terminal holding piece for holding a connecting terminal, fixing the terminal pin to a point end part of the terminal holding piece, and connecting a lead wire of the coil. CONSTITUTION:A bobbin 13 is partly extended to form a terminal holding piece 15 for holding a connection terminal, and a long and narrow groove 16 of width equal to a terminal pin is engraved in a point end part of the terminal holding piece to provide a through hole 17 of internal diameter equal to a diameter of the terminal pin drilled in one end of the groove. The terminal pin, folded in a crank shape, is inserted so as to be fitted to these groove 16 and through hole 17. A lead wire of a driving coil 12 is wound to an internal end part of the terminal pin to put the terminal pin in continuity to the drive coil. On the other hand, constitution is provided such that an external side end part of the terminal pin, long protruded to the outside from a surface of the terminal holding piece 15, can be inserted to a circuit board or the like.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a motor with a terminal, and in particular, a part of a bobbin that holds a driving coil of the motor is extended to a predetermined position, and a terminal pin is fixed to the tip of the bobbin, so that a terminal pin can be fixed to the tip of the bobbin. The present invention relates to a terminal-equipped motor that has connection terminals at predetermined positions and can be directly mounted on a circuit board or the like.

0002

[Prior Art] Generally, a motor has a connection terminal at a fixed position relative to the motor body, and this connection terminal is connected to an external motor drive power source, a circuit board, a lead wire connector, or a flexible printed circuit (hereinafter referred to as FPC). ) and other connecting parts.

FIG. 4 shows a cross section of a PM type stepping motor, which is one of the conventional motors. A conventional PM type stepping motor 21 has a motor body 22, a gear 23, and a plastic case 24 that houses the motor body 22 and gear 23. The motor main body 22 is fixed inside a plastic case 24 so as not to swing, and the rotation of the rotation shaft 24 of the motor is extracted to the outside via a gear 23. The current for driving the motor is supplied via the connection terminal 25. The PM type stepping motor 21 is fixed to a fixing member 26 of a device to be incorporated, and the connection terminal 25 of the PM type stepping motor 21 and an external power source are connected via a lead wire connector 27. The current of the power source is controlled by a control circuit (not shown), and the controlled current is supplied to the PM type stepping motor 21 through the lead wire connector 27, so that the PM type stepping motor 21 performs a controlled rotational operation.

FIG. 5 shows a cross section of a motor body 22 of a PM type stepping motor 21. As shown in FIG. The motor body 22 is
A cylindrical permanent magnet rotor 28 that rotates together with the rotating shaft 24
and an annular drive coil 29 surrounding the permanent magnet rotor 28. As shown in the figure, the outer peripheral surface of the permanent magnet rotor 28 is magnetized so as to have north and south pole magnetism alternately in the circumferential direction. The drive coil 29 is held by a bobbin 30, and a yoke 31 forming a magnetic path is provided further inside the bobbin 30. The yoke 31 has a plurality of sawtooth magnetic poles (not shown) on its inner peripheral surface adjacent to the permanent magnet rotor 28, and
When a current is passed through 9, these magnetic poles are excited, thereby driving the permanent magnet rotor 28 to rotate. A portion of the bobbin 30 bulges out to form a terminal pin holding portion 33 that holds the terminal pin 32. The terminal pin holding portion 33 holds one end of the rod-shaped terminal pin 32 and causes the terminal pin 32 to protrude outside the motor body 22 . A conductive wire 34 of the drive coil 29 is wound around the base of the terminal pin 32.
The terminal pin 32 and the drive coil 29 are electrically connected to each other.

[0005]

[Problems to be Solved by the Invention] However, in the above-mentioned conventional motor, the connection terminal is provided at a fixed position with respect to the motor body, and it is difficult to connect the connection terminal using a connection part such as a lead wire connector or FPC. Must be connected to an external power source or circuit board. Lead wire connector and FPC
Since the connection terminals of the motor are connected to an external power source, etc., the number of parts increases, and the process of assembling the motor becomes complicated. Further, there was a problem in that the reliability of soldering at the connection part was low, and the possibility of connection failure was high. In addition, in conventional motors, a part of the bobbin bulges out to form the terminal pin holding part, so it is necessary to cut out a large part of the casing of the motor body, and the magnetic flux flows from the cut-out opening in the motor casing. There were problems with leakage and poor motor efficiency. Furthermore, the terminal pins of conventional motors are installed with one end buried inside the terminal holding member while remaining in a straight shape, or are installed through the terminal holding member, so the installation strength is insufficient. However, when winding the conductive wire of the coil, there was a problem that the terminal pins were inclined with respect to the holding surface of the holding member or fell off. SUMMARY OF THE INVENTION An object of the present invention is to provide the connection terminals of the motor at a preferable predetermined position on the mounting surface of the motor, thereby allowing the motor to be directly mounted on a circuit board, and further avoiding the problem of magnetic flux leakage from the motor casing. It is an object of the present invention to provide a motor with terminals which has high motor efficiency by reducing the size of the notch and has a strong attachment strength for terminal pins.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the motor with terminals of the present invention extends a part of the bobbin that holds the drive coil to a predetermined position within the mounting surface of the motor, and provides connection terminals. A terminal holding piece is formed to hold the terminal, a terminal pin is fixed to the tip of this terminal holding piece, a coil conductor is connected to a part of the terminal pin, and the outer end of the terminal pin is connected to the connection part of the circuit board. This is characterized by direct connection. Further, the terminal pin of the motor with a terminal of the present invention is characterized in that the terminal pin is bent so that both ends protrude almost vertically from both sides of the terminal holding piece, and the center portion is held over a predetermined length by the terminal holding piece. It is something to do.

[0007]

[Operation] In the motor with terminals of the present invention, a part of the bobbin that holds the drive coil is extended to a predetermined position within the mounting surface of the motor, and the connecting terminal is held at the tip of the bobbin, so that the motor It is possible to have a connection terminal at any position within the mounting surface. This allows lead wire connectors and
It is possible to obtain a motor with terminals that can be directly mounted on a circuit board or the like without using connection parts such as a PC. In addition, the terminal pin for connection of the terminal-equipped motor of the present invention is bent and the center portion is held over a predetermined length by the terminal holding piece, so the installation strength of the terminal pin is high, and the end of the terminal pin has a coil attached to it. The terminal pin will not tilt or fall out when winding the conductor.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a state in which a PM type stepping motor as an example of a terminal-equipped motor according to the present invention is mounted on a circuit board. The PM type stepping motor 1 according to the present invention includes a motor body 2, a plurality of gears 3 for transmitting power of the motor body 2, and the motor body 2 and the gears 3.
and a plastic case 4 for storing the. The motor body 2 is arranged inside a plastic case 4,
It is fixed to the plastic case 4 so as not to swing. The output gear 3a of the motor is fitted onto the rotating shaft 5 of the motor body 2, and is configured to rotate together with the rotating shaft 5. The rotation of the output gear 3a of the motor is transmitted via the plurality of gears 3 to the external output gear 3b. The PM type stepping motor 1 has a connection terminal 6 for connection to a circuit board 8 at a position remote from the motor body 2. The terminal pins 7 of the connection terminals 6 are inserted into circuit connection portions of the circuit board 8 and fixed by soldering on the back surface of the circuit board 8. Further, the plastic case 4 has PM
A mounting surface 9 of the stepping motor 1 on the circuit board 8 is provided with a protruding fixing pin 10, and the fixing pin 10 is inserted into an opening provided in the circuit board 8. The PM stepping motor 1 is fixed to the circuit board 8 by the fixing pin 10 and the connection terminal 6, and will not fall off. For example, a circuit for controlling the rotation of the motor is built into the circuit board 8, and current from an external power source (not shown) is supplied to the connection terminal 6 of the PM stepping motor 1 via the circuit board 8. Since the controlled current is supplied to the motor main body 2 as described above, the motor main body 2 performs a controlled rotational movement, and this controlled rotational movement is finally transmitted to an external output gear via a plurality of gears 3. 3b is output to the outside.

FIG. 2 shows only the motor body 2 of the PM type stepping motor 1 in an enlarged manner. The motor body 2 is
It has a cylindrical permanent magnet rotor 11 supported so as to rotate integrally with the rotating shaft 5. The outer circumferential surface of the permanent magnet rotor 11 is magnetized to have north and south pole magnetism alternately in the circumferential direction. An annular driving coil 12 is provided on the outer periphery of the permanent magnet rotor 11 so as to surround the permanent magnet rotor 11. The driving coil 12 is held by a bobbin 13, and inside this bobbin 13,
A yoke 14 forming a magnetic path is provided. yoke 1
4 has a plurality of serrated magnetic poles (not shown) on the inner circumferential surface adjacent to the permanent magnet rotor 11, and when a current is passed through the drive coil 12, the magnetic poles are excited, and the permanent magnet rotor 11 is driven to rotate. is configured to do so. A portion of the bobbin 13 is stretched to form a terminal holding piece 15 that holds the connection terminal 6.
form. An elongated groove 16 having a width equal to that of the terminal pin 7 is cut at the tip of the terminal holding piece 15, and a through hole 17 having an inner diameter equal to the diameter of the terminal pin 7 is bored at one end of the groove 6. A terminal pin 7 bent into a crank shape is inserted so as to fit into the groove 16 and the through hole 17. Both ends of the terminal pin 7 protrude from both sides of the terminal holding piece 15, and the center portion of the terminal pin 7 is held between the groove 16 and the plastic case 4 (not shown). As a result, the terminal pin 7 is firmly held at the tip of the terminal holding piece 15, and the terminal pin 7 does not tilt relative to the terminal holding piece 15 or fall off. A conductive wire 18 of the drive coil 12 is wound around the inner end of the terminal pin 7 to establish electrical continuity between the terminal pin 7 and the drive coil 12. On the other hand, the outer end of the terminal pin 7 protrudes outward from the surface of the terminal holding piece 15 and is configured to be inserted into the circuit board 8. The conductive wire 18 of the coil is laid along the terminal holding piece 15 to prevent it from being cut by external force.

FIG. 3 shows a cross section of the PM type stepping motor 1 of the present invention as seen from the mounting surface 9. Said bobbin 1
3 is partially extended to form a terminal holding piece 15. This terminal holding piece 15 is formed so that its tip is aligned with a predetermined connection position on the circuit board 8 . P of this example
The M-type stepping motor 1 has a terminal pin 7 in FIG.
Although the terminal pins 7 are arranged at the upper part of the motor mounting surface 9, the position of the terminal pins 7 is not limited to this, and the connection terminals 6 can be provided at any position that matches the connection position of the circuit on the circuit board 8. can. In this case, the terminal holding piece 15 may be formed by extending it to a predetermined position, and the plastic case 4 may be molded into a shape that can accommodate the terminal holding piece 15. Furthermore, in FIG. 3, the notch 19 of the motor case of the motor body is drawn large for the sake of understanding, but this notch 19 causes magnetic flux leakage and reduces the efficiency of the motor.
It is preferable that the opening of the notch 19 be made small. According to the PM type stepping motor 1 of the present invention, the opening of the notch 19 only needs to have the thickness and width of the portion of the terminal holding piece 15 that penetrates the motor case.
9 can be made smaller. This makes it possible to reduce magnetic flux leakage and obtain a PM stepping motor 1 with high motor efficiency.

[0011] In this embodiment, a PM type stepping motor has been described, but it goes without saying that the invention can be similarly applied to other motors.

0012

[Effects of the Invention] As is clear from the above description, the terminal-equipped motor of the present invention extends a part of the bobbin to a predetermined position within the mounting surface of the motor to form a terminal holding piece that holds the connection terminal. , fix the terminal pin to the tip of this terminal holding piece,
Since the conductor of the motor drive coil is connected to a part of this terminal pin, the terminal pin can be set at any position on the mounting surface of the motor. This allows the motor to be mounted directly on the circuit board, eliminating the need for connection parts such as lead wire connectors and FPCs, which simplifies the process of assembling the motor and improves the reliability of electrical connections. It can be made higher. Further, according to the terminal-equipped motor of the present invention, since the opening of the penetrating portion of the terminal holding piece that penetrates the motor case can be made small, it is possible to obtain a terminal-equipped motor with less magnetic flux leakage and high motor efficiency. Furthermore, the terminal pin of the terminal-equipped motor of the present invention is bent and both ends protrude from both sides of the terminal holding piece, and the central part is held over a certain length, so the installation strength is high and the driving coil can be attached to the terminal pin. When winding the conductor, the terminal pin will not tilt or fall off.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a PM stepping motor of the present invention mounted on a circuit board.

FIG. 2 is a sectional view of the motor body of the PM stepping motor of the present invention.

FIG. 3 is a front sectional view of a PM type stepping motor of the present invention.

FIG. 4 is a side sectional view of a conventional motor with terminals connected to a lead wire connector.

FIG. 5 is a sectional view of a motor body of a conventional PM stepping motor.

[Explanation of symbols]

1 PM type stepping motor 6 Connection terminal 7 Terminal pin 8 Circuit board 9 Motor mounting surface 13 Bobbin 15 Terminal holding piece

Claims (3)

[Claims] Claim 1: A part of a bobbin that holds a driving coil is extended to a predetermined position to form a terminal holding piece that holds a connection terminal, and a terminal pin is fixed to the tip of this terminal holding piece,
A motor with a terminal, characterized in that a conductor of a coil is connected to a part of the terminal pin, and the outer end of the terminal pin is directly connected to a connection part of a circuit board. 2. The motor includes a plastic case that houses the main body of the motor with terminals and a terminal holding piece, and has one end of the terminal pin protruding from an arbitrary position on a mounting surface of the motor on a circuit board. A motor with a terminal according to claim 1. 3. The terminal pin is bent so that both ends protrude substantially perpendicularly from both sides of the terminal holding piece, and the center portion is held over a predetermined length by the terminal holding piece. Motor with terminals listed.