JPS5934062B2 - Brushless DC motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention detects the rotational position of the rotor using a high-frequency coupling type rotational position detection mechanism, and sequentially controls the energization of the armature windings of each phase based on the rotational position detection signal obtained from the rotational position detection mechanism. This brushless DC motor is designed to facilitate the assembly of a part of the stator.

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 1 is a side sectional view of an embodiment of the present invention, and FIG. 2 is an exploded perspective view of essential parts of the embodiment.

In those figures, two ball bearings 12 are fixed to the upper and lower openings of a cylindrical housing 10.
A preload boss 18 for applying preload to the ball bearing 12.14 is fixed to the lower end of the main shaft 16 rotatably supported by a screw 14 with a screw 17.
An external rotor unit 22 is attached to the lower end surface of the housing 10 by screws 19, and is rotatably held in a position opposite to the stator unit 20 fixed at a predetermined position of the housing 10. It consists of

The rotor unit 22 has a structure in which a position detection unit 28 using high frequency induction and a ring-shaped drive magnet 30 are arranged in an upper and lower positional relationship on the inner wall of a magnet case 26 made of a magnetic material, A short ring 32 made of a conductive non-magnetic material is fixed to the inner wall surface of the position detection unit 28, and has a required number of openings formed at equal angular intervals to perform high frequency modulation. For example, on the outer periphery of the motor part 24
When the rotor unit 2 is incorporated into a direct drive rotary head cylinder device, etc., the rotor unit 2 is used as a means for informing the position of the rotary video head, that is, the rotational phase.
A phase detection magnet 34 for generating an electric signal according to the 20-rotation position is embedded.

Next, the configuration of the stator unit 20 corresponding to the rotor unit 22 will be explained with reference to FIG. 2.

40 is a resin base integrally having three positioning pieces 36 and two elastic locking pieces 38 protruding in the same direction (upward in the drawing); 44 is each wound with a position detection coil 42; A ring-shaped position having three sets of two protrusions 44a integrally arranged radially at predetermined angular intervals on the outer periphery so that three sets of two position detection coil bobbins 43 can be inserted and attached. This is a detection iron core, and a positioning protrusion 46 integrally provided in the resin base 40 so as to protrude downward is press-fitted from above into a hole 45 provided in the core, and a holder 48 disposed below. The position detecting iron core 44 is sandwiched between the upper resin base 40 and the upper resin base 40, and the three are integrally connected with screws 41.

Note that 37 and 47 are through holes for inserting the screws 41 provided in the resin base 40 and the position detection iron core 44, respectively, and 49 is a screw hole for the screws 41 provided in the holder 48.

A stator core 52 made of a laminated steel plate on which an armature winding 50 is applied in a three-phase configuration is fixed to the other end surface of the holder 48 with screws 51. The leg portion 54a is press-fitted into the formed hole 53 and connected to a conductive pin 54b of a resin stator terminal 54 held therein.

In fact, in the resin base 40, there is a phase detection coil unit 56 having a phase detection coil 55 at a position where the phase detection magnet 34 buried in the outer periphery of the magnet case 26 can face the phase detection coil unit 56. (legs) 5
7 is press-fitted into a circular hole of a phase detection coil unit mounting portion 59 integrally formed on the resin base 40.

Furthermore, the conductive pins 54b, 55a, and 42a to which the winding ends of the stator terminal 54, phase detection coil unit 56, and position detection coil 42 are connected are tightly attached to the upper surface of the resin base 40 while maintaining a predetermined positional relationship. The ring-shaped printed circuit board 58 is inserted into a plurality of corresponding holes 60.

Here, the aforementioned resin base 40 is attached to the printed circuit board 58.
A notch 62 is positioned by the positioning piece 36 protruding from the top, and a notch 64 is locked by the locking piece 38. At the same time, the conductive pins 54b of the stator terminal 54, the phase detection coil unit 56, and the position detection coil 42 are inserted through the holes 60 described above.

55a and 42a are soldered to the required circuit copper foil formed on the printed circuit board 58 for wiring processing.The circuit steel foil of the printed circuit board 58 has a plurality of lead wires (not shown). is connected to the motor drive circuit (not shown).

In the brushless DC motor according to the present invention configured as described above, as each component is assembled, each winding end is automatically placed at a predetermined position, and the ends of the windings are placed at a predetermined position on the printed circuit board. Since the printed circuit board is locked and fixed to the above-mentioned resin-based locking piece, it is easy to assemble.
In particular, the wire processing workability of each winding can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an embodiment of the present invention, and FIG. 2 is an exploded perspective view of essential parts of the embodiment of the present invention. 10...Housing, 16...Main shaft,
20... Stator unit, 22...
・Rotor unit, 24...Motor part, 2
6... Magnet case, 30... Drive magnet, 34... Phase detection magnet,
36... Positioning piece, 38... Locking piece, 40... Resin base, 41, 51...
・Screw, 42...Position detection coil, 42a...
... Conductive pin, 43 ... Position detection coil bobbin, 44 ... Position detection iron core, 45 ...
... Hole, 46 ... Positioning protrusion, 48 ...
...Holder, 50...Armature winding, 52...
・Stator iron core, 54... Stator terminal, 54b... Conductive pin, 55...
・Phase detection coil, 55a... Conductive pin, 5
6... Phase detection coil unit, 57...
... Positioning engagement part, 58... Eleventh board, 59... Phase detection coil unit mounting part,
60... Hole, 62, 64... Notch.

Claims (1)

[Scope of Claims] 1. A printed circuit board in which a positioning portion and a locking portion are formed at required locations, and a positioning piece located on the positioning portion of the printed circuit board on one surface and capable of being locked in the locking portion. A resin base on which a locking piece is integrally formed, a required number of positioning protrusions are integrally formed on the other side, and a conductive conductor with a position detection coil wound thereon and connected at the 70 wire end. a required number of position detection coil bobbins having conductive pins, and the position detection coil bobbins are mounted on the outer periphery at predetermined angular intervals such that the conductive pins protrude toward the printed circuit board; a stator terminal having a position detection core having a hole into which a resin-based positioning protrusion can be fitted; and a conductive pin having an armature winding and having a wire end of the armature winding connected to the printed circuit board side. a stator core equipped with the stator terminal, and a first screw hole that is attached to the side of the stator core where the stator terminal is equipped, and for positioning and fixing the stator core with screws, and the resin base. a holder having a second screw hole for positioning and fixing; the printed circuit board is positioned and attached to one surface of the resin base, and the position detection iron core is mounted to the other surface of the resin base. The conductive pins of the position detection coil bobbin are positioned and coupled to the holder so that they protrude toward the printed circuit board, and the stator iron core is attached to the armature on the surface of the holder opposite to the position detection iron core. The conductive pins of the stator terminal, to which the wire ends of the windings are connected, are positioned and fixed so that they protrude toward the printed circuit board, and the conductive pins of the stator terminal and position detection coil bobbin are connected to the required circuit copper foil of the printed circuit board. A brushless DC motor characterized by being configured to last for a long time. 2 A phase detection magnet is installed in the magnet case that constitutes the rotor unit, which is arranged to be rotatable outside the stator core, and a phase detection coil and the wire ends of the phase detection coil are connected to the resin base. A phase detection coil unit having a conductive pin is arranged such that the phase detection coil faces the phase detection magnet, and the conductive pin to which the wire end of the phase detection coil is connected is connected to a desired circuit copper foil of a printed circuit board. 2. The brushless DC motor according to claim 1, wherein the brushless DC motor is mounted so as to be continuously operated.