JPS5818455Y2 - Motor coil mounting structure - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a coil attachment structure for attaching a motor coil to a stator.

First, referring to FIG. 7, a conventional example of a motor for driving a turntable in a record player will be described. A stator housing (lower yoke) 46 is screwed to the lower part of a frame 45, and a stator housing (lower yoke) 46 is integrally molded in the center of the stator housing 46. A bearing 48 is press-fitted into the bearing case 47, and a motor shaft 49 is vertically supported by this bearing 48.

A rotor housing (upper yoke) 51 and a turntable 52 are attached to the upper part of the motor shaft 49 via a mounting bracket 50, and an annular permanent magnet 53 is bonded to the lower surface of the rotor housing 51.

A printed circuit board 54 is mounted on the stator housing 46 at a position facing the lower surface of the permanent magnet 53, and a plurality of coils 60 each wound around a bobbin 59 are mounted on the printed circuit board 54 in a predetermined arrangement. It is placed.

Each bobbin 59 is usually positioned with respect to the printed circuit board 54 by a fitting structure using a plurality of positioning dowels 61 and holes 62, and then screwed in a state collinear with the printed circuit board 54 with a set screw 63. has been done.

However, in the conventional stator housing 46, the coil 6
0, first, the bobbin 59 and the stator housing 46 are fitted (step a).

Next, the coil 60 is wound around the bobbin 59 (step b).

Next, the bobbin 59 with the coil 60 wound thereon is positioned and attached to the stator housing 46 (step C).

Finally, the positioned bobbin 59 is screwed to the stator housing 46 (step d).

It is necessary to go through the steps a to d, and the installation takes a lot of time, and the workability is poor and the cost is extremely high. In addition, the positioning by fitting the dowel 61 and the hole 62 is It had defects in that it was prone to rattling and the positioning accuracy was reduced.

The present invention was devised in order to correct the above-mentioned defects, and the metal chassis on the stator side of the motor is provided with a plurality of through holes for positioning the bobbin, and these through holes are used to A single flange-shaped bobbin and an elastic coil locking pawl integrated with the bobbin are provided on the chassis by outsert molding of synthetic resin, and the air-core coil resists the elasticity of the coil locking pawl. The coil mounting structure of the motor is such that the coil is fitted onto the outer periphery of the bobbin and the coil is locked by the coil locking claw.

With this configuration, the coil can be installed very easily and the positioning accuracy can be increased.

An embodiment in which the present invention is applied to a turntable driving motor in a record player will be described below.

First, an overview of the motor 1 will be explained with reference to FIGS. 1 and 2. 2 is the upper frame of the record player; 3 is the upper frame of the record player;
indicates a turntable.

In this case, the lower yoke 4, which constitutes the metal chassis on the stator side of the motor 1, is made of a flat iron plate and is arranged at the lower part of the frame 2, and is installed on the lower surface of the frame 2 by crimping or the like. It is screwed to a plurality of screw tightening bosses 5 by set screws 6.

A bearing 7 is attached to the center of the lower yoke 4, and an upper yoke 9 constituting the rotor housing of the motor 1 is attached to the upper part of the motor shaft 8, whose lower end is inserted into the bearing 7 and supported vertically. It is fixed via 10.

The turntable 3 is inserted into a conical portion 10a formed at the upper end of the mounting bracket 10 from above.

A permanent magnet 1 having an annular shape is attached to the lower surface of the upper yoke 9.
A plurality of coils 12 facing the lower surface of the permanent magnet 11 are attached to the upper surface of the lower yoke 4.

Therefore, in this motor 1, the stator housing has a flat plate shape, and the stator is composed of a lower yoke 4 and a coil 12 attached to the lower yoke.

In addition, the lower yoke 9 constitutes a rotor housing,
This upper yoke 9 and the permanent magnets 11 attached thereto constitute a rotor.

Note that 13 is a steel ball for receiving the thrust of the motor shaft 8.

Regarding the attachment of the bearing 7 to the lower yoke 4, this motor 1 has a structure in which the bearing 7 is integrally molded with the lower yoke 4 by outsert, as shown in FIG.

That is, in this case, the bearing 7 has a substantially cylindrical bearing body 7a which is inserted from above into a hole 14 formed in the lower yoke 4 by means of its base 7b, and is integrally molded above and below this base 7b. Lower yoke 4 with a pair of flange parts 7C
is held between the top and bottom.

Both flange portions 7C are integrally connected to each other by a connecting portion 7d at a plurality of holes 15 formed around the hole 14 of the lower yoke 4.

Note that the above-mentioned outsert refers to the state in which the lower yoke 4 in which the above-mentioned holes 14 and 15 are formed in advance is inserted into the mold,
This is a method of integrally molding the bearing 7 with the lower yoke 4 by injection molding the bearing 7 of synthetic resin using the mold.

In this case, the material for the bearing 7 is a self-lubricating resin such as Delrin or Duracon.

Therefore, there is no need to press fit metal or the like into the bearing 7.

If the bearing 7 is configured to be outsert to the lower yoke 4 as described above, the bearing may be press-fitted into the bearing case integrally molded into the stator housing, or the bearing and bearing case may be attached using screws. Compared to the above, the number of man-hours and parts cost required for the installation can be reduced, and a resin made of the bearing 7 is interposed between the lower yoke 4 and the motor shaft 8.

Vibration isolation can be expected, and it is also very advantageous in terms of S/N.

When it is necessary to ground the motor shaft 8, for example, as shown in FIG. 4, a conductive metal bearing 18 is buried entirely or partially within the bearing body 7a of the bearing 7. The metal bearing 18 may be grounded, and depending on the case, a plate spring, wire spring, etc. may be brought into direct contact with the motor shaft 8.

Note that the metal bearing 18 can also be outserted to the lower yoke 4 at the same time as the bearing 7.

Furthermore, it goes without saying that if the metal bearings 18 are embedded in the entire bearing 7, the bearing 7 becomes a so-called bearing case.

Further, when the metal bearing 18 is entirely buried within the bearing 7 as described above, it is convenient when a large thrust load is applied to the motor shaft 8, for example, when the motor 1 is used horizontally.

Although the lower yoke 4 described above has a flat plate shape, it goes without saying that if it is formed into a cylindrical shape, the lower yoke 4 can directly serve as a stator housing.

Further, the plurality of coils 12 for the lower yoke 4
Regarding the installation of 2.3 in this motor 1,
, 5.6, the structure is such that the bobbin 20 of each coil 12 is outsert to the lower yoke 4.

That is, in this case, the plurality of bobbins 20 each have a substantially trapezoidal planar shape in terms of structure and constitute a single flange-shaped bobbin having a flange portion only at the lower end, and the coil is fitted onto the substrate portion 20a. The wall covering part 20b is raised,
A lower end peripheral portion of the rugged coil fitting wall portion 20b is formed into a flange portion 20C.

Then, the base 20 is inserted into holes 21 and 22, which are through holes formed in the lower yoke 4 at, for example, three locations approximately in the center of the substrate portion 20a and around the coil fitting wall portion 20b.
Connecting portions 20d and 20e wrap around the lower surface side of the lower yoke 4 from the flange portion 20C and the flange portion 20C to grip the lower yoke 4.

Note that the above-mentioned outsert is a state in which the lower yoke 4, in which the holes 21 and 22 are previously formed in a predetermined arrangement, is inserted into a mold, and the plurality of bobbins 20 are made of synthetic resin using the mold. This is a method of integrally molding these bobbins 20 with the lower yoke 4 by injection molding.

In this case, various synthetic resins can be used as the material for the bobbin 20.

On the other hand, elastic coil locking claws 23 are integrally formed at, for example, three locations on the coil fitting wall portion 20b.

Note that 24 is a hole for undercutting when forming the coil locking claw 23.

Further, for example, at the four corners of the coil fitting wall portion 20b, a sixth
A tapered surface 25 is formed as clearly shown in the figure.

Note that 26 is a hole for undercutting when forming the tapered surface 25.

On the other hand, the plurality of coils 12 are configured as so-called air-core coils.

Note that this air-core type coil is a bare wire coated with heat-weldable material, which is tightly wound into a substantially trapezoidal shape along the coil fitting wall portion 20b, and then the bare wire is coated with, for example, l.
A current of ~3A is applied to heat-weld the bare wires together and form them.

As for attaching each coil 12 to each bobbin 20, the air-core coil 12 is fitted from above around the coil fitting wall 20b of the bobbin 20 that is outsert to the lower yoke 4 in advance as described above. Just let it happen.

By this fitting, the plurality of coil locking claws 23 lock the coil 12 with their claws, and the tapered surface 25 is brought into close contact with the inner peripheral surface of the coil 12, making it impossible to remove the coil 12 from the bobbin 20. A stop is made.

However, in this case, the coil 12 can also be bonded to the bobbin 20 if necessary.

When the coil 12 is configured to be attached to the lower yoke 4 as described above, the coil 12 can be attached to the bobbin 20 in a so-called one-touch manner. Installation is very easy and quick.

Furthermore, although the bobbin 20 is integrally molded in advance at a predetermined position on the lower yoke 4 by outsert, the coil 12 can always be attached to the correct position extremely accurately, and the trouble of positioning and screwing can be saved.

In FIG. 2, reference numeral 28 is a printed circuit board mounted at a predetermined position between the coils on the upper part of the lower yoke 4, and the plurality of coils 12 are appropriately wired to the conductive patterns of the printed circuit board 28.

Further, a position detecting element 29 such as a Hall element is attached to the printed circuit board 28, and the permanent magnets are sequentially magnetized to N, S, N, S, etc. along the circumferential direction. 11 position detection is performed.

As mentioned above, the present invention provides a bobbin on the metal chassis on the stator side of the motor by outsert molding of synthetic resin, which replaces the conventional method of attaching the bobbin to the metal chassis with eyelets, screws, or crimping.・It is possible to completely eliminate the trouble of positioning the bobbin, fixing it with grommets, screws, or caulking, and the positioning accuracy of the bobbin and the coil to which it is attached can be extremely high. In this case, the bobbin is formed into a single flange shape, and when the bobbin is outsert molded, an elastic coil locking pawl is integrally provided on the bobbin, and an air-core type The coil is fitted onto the outer periphery of the bobbin against the elasticity of the coil locking pawl, and the coil is locked by the coil locking pawl. Installation can be done extremely easily and quickly by simply pushing the coil onto the outer periphery of the bobbin, which significantly improves the work efficiency of installing the coil, and also makes it easier to install the coil during service. It is also extremely easy to remove the coil from the bobbin, and serviceability can be significantly improved.

However, the coil locking pawl is outsert-molded integrally with the bobbin, and the coil locking pawl and the bobbin constitute a single part, and these are made up of separate parts and made of metal. Because it is completely different from the structure assembled on the chassis,
The structure and manufacture are extremely simple, and costs can be significantly reduced.

[Brief explanation of drawings]

1 to 6 show an embodiment in which the present invention is applied to a turntable drive motor for a record player. Plan view, Figure 3 is a sectional view taken along line III-III in Figure 2,
Figure 4 is a sectional view of the main parts showing a modified example of the bearing, Figure 5 is an exploded perspective view of the bobbin and coil portion, and Figure 6 is Figure 2V.
It is a sectional view taken along the line I-VI. FIG. 7 is a longitudinal sectional view illustrating a conventional example. Also, in the symbols used in the drawings, 1 is the motor, 4 is the lower yoke which is the metal chassis on the stator side, 12 is the coil, and 20 is the motor.
is the bobbin, 20b is the coil fitting wall of the bobbin, 20C
2 is a flange portion of the bobbin, and 23 is a coil locking claw.

Claims (1)

[Scope of utility model registration request] A plurality of through holes for positioning the bobbin are provided in the metal chassis on the stator side of the motor, and a single flange-shaped bobbin and an elastic coil integrated with the bobbin are mounted on the metal chassis using the plurality of through holes. A locking pawl is provided by outsert molding of synthetic resin, and an air-core coil is fitted onto the outer periphery of the bobbin against the elasticity of the coil locking pawl. The structure of the motor coil installation is such that the coil should be locked.