JP2585666Y2 - Bobbin structure of sealed coil - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bobbin structure for a sealed coil of a small motor.

[0002]

2. Description of the Related Art In small motors, it is required to improve the strength and insulation of a coil set, and it is necessary to strengthen and seal the coil set. According to conventional manufacturing technology,
Among the demands for thinning, those satisfying them could not be provided. As the cause, the strength of the bearing portion of the bobbin and the variation of the bearing accuracy at the time of injection of the sealing material, problems such as warpage of the flange portion occur, and as a result, the sealing material cannot be injected by a predetermined amount, One reason is that the target quality could not be secured. In particular, when the flange is made thin, the flange is deformed when the sealing resin is injected, and the resin does not completely enter the mold space, so that a sufficient sealing state cannot be obtained, and the incidence of product defects is high. Was.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to prevent deformation of a flange portion during molding while reducing the thickness of the entire bobbin, and to form a strong bearing with a part of the flange accurately.

[0004]

According to the present invention, a bobbin inner hole is formed inside a cylindrical winding drum, and flanges are integrally formed at both ends of the winding drum. In a bobbin structure of a sealed coil in which a coil is wound around a body, an annular thick portion starting from the bobbin inner hole is formed in the flange to reinforce the flange, and further to the outside of one flange of the bobbin.
In a sealed coil having a bearing portion of an output shaft on the front end side of a bobbin inner hole in a surface, an annular thick portion starting from the bobbin inner hole and extending to a half or more of a diameter of the bearing portion is formed in a flange portion. Thereby, the flange portion and the bearing portion are integrated and strengthened, the deformation of the flange portion and the bearing portion during molding is prevented, and they can be completely surrounded by the sealing material.

[0005]

1 shows a sealed coil 1, and FIGS. 2 and 3 show the structure of a bobbin 2. FIG. The sealing coil 1 is composed of a bobbin 2, a coil 3, and a sealing material 4 surrounding them.

The bobbin 2 is made of, for example, nylon 66, and has a bobbin inner hole 7 formed inside the cylindrical winding drum 5 and a flange 6 integrally formed at both ends of the winding drum 5. doing. These flanges 6 are provided on the outer surface of the flange 6.
In addition , an annular thick portion 9 is integrally formed at an outer peripheral portion of the bobbin inner hole 7, and an annular thick portion 10 is formed at an appropriate interval outside the thick portion 9 as necessary. doing.

[0007] One of the flanges 6 has an outer surface.
In addition, the bearing portion 8 and the terminal block 11 are integrally formed on the front end (outer peripheral) side of the flange portion 6 with respect to the bobbin inner hole 7 . The thick portion 9 starts from the bobbin inner hole 7 and extends over half of the diameter of the bearing portion 8. As a result,
The bearing portion 8 covers a part of the thick portion 9 on the center side.
Thus, the bearing portion 8 and the thick portion 9 are integrated by a thick portion. In addition, for example, four protrusions 12 for fixing pole teeth 22 described later are formed at an appropriate interval in the portion of the bobbin inner hole 7.

A coil 3 is wound around the bobbin 2,
Its end is connected to a terminal 13 attached to a terminal block 11. In this state, as shown in FIG.
The coil 3 is housed inside the mold 14, and a sealing material 4 such as resin is injected from an injection port 15. At this time, the sealing material 4 wraps the outside of the bobbin 2 and the coil 3 and puts them in a sealed state in order to enhance the waterproof / insulating function. At this time, since the bearing portion 8 and the thick portion 9 are in contact with the inner surface of the molding die 14, their end surfaces are at the same height as the surface of the sealing material 4. The inner surface of the bobbin inner hole 7 and the tip of the terminal 13 are not covered with the sealing material 4.

Since the flange 6 is sufficiently reinforced at its central portion by the thick portion 9, even if the flange 6 receives the injection pressure from the inner surface during the injection of the sealing material 4, It does not bend outward and hardly deforms. Therefore, the sealing material 4
Is sufficiently distributed in the internal space of the molding die 14, and the injection failure is not particularly caused on the outer surface of the flange 6. After this molding, the outer annular thick portion 10 is not exposed from the sealing material 4, but is bonded to the inner peripheral surface thereof by unevenness, and the thick portion 9 and the molded sealing material 4 are not exposed. The waterproof effect and the insulating effect are enhanced by increasing the creepage distance from the gap to the inner coil 3.

Next, FIG. 4 shows an example in which the sealed coil 1 is incorporated in a small motor 20 with a speed reducer. The sealing coil 1 is housed in a cap-shaped motor case 21. At this time, the pole teeth 22 formed by the motor case 21 are located between the protrusions 12 inside the bobbin inner hole 7 and face the outer peripheral surface of the permanent magnet rotor 23. The core 24 is fitted into the motor case 21, and a plurality of gears 26 and 27 are incorporated between the core 24 and the end cap 25.

The rotation of the rotor 23 is transmitted to a gear 26 by a pinion 29 fixed to a rotor shaft 28, and further transmitted to an output gear 27 by a plurality of gears (not shown). The gear 27 is integral with the output shaft 30, and the small shaft 31 of the output shaft 30 fits inside the bearing 8, and the large shaft 32 is a bearing 33 formed on the end cap 25. Supported by Here, since the bearing portion 8 is sufficiently reinforced by being integrated with the thick portion 9, the end cap 2
The output shaft 30 is stably supported in a rotatable state together with the fifth bearing portion 33.

[0012]

[Effects of the Invention] The present invention has the following effects. Claim 1
According to, for the inner circumferential i.e. root portion of the flange portion is reinforced by the thick portion of the annular starting from bobbin bore, the flange
The strength of the part is increased, there is no deformation such as warping when the sealing material is injected, dimensional accuracy is easily obtained, and the injection of the sealing material
The position and shape of the mouth can be freely selected, and the molding conditions are also flexible
And lead wire breakage during the molding process and resin material selection
Molding becomes easy from the point of constant. Moreover, bobbin inner hole
From the annular thick part starting from
Sealed with a stopper material and formed thinner than the thick part
Since the thin part is formed continuously over the entire circumference of the collar,
Due to the joint surface between the part and the sealing material, the creepage distance becomes longer,
Moreover , deformation such as warpage of the thin flange after molding is eliminated.

According to the second aspect , since the annular thick portion is integrated with the bearing portion with a diameter of 1/2 or more, the bearing portion is strengthened and the support of the rotating shaft is stabilized.

Further, according to the third aspect, since the annular thick portions are formed at predetermined intervals outside the annular thick portions starting from the bobbin inner holes, the irregularities due to those thick portions are formed. Thereby, the connection between the thick portion and the sealing material is strengthened, and the creepage distance is further increased, whereby the waterproofing / insulating effect is enhanced.

[Brief description of the drawings]

FIG. 1 is a plan view of a sealing coil.

FIG. 2 is a plan view of a bobbin.

FIG. 3 is a cross-sectional view when a sealing resin is injected.

FIG. 4 is an enlarged sectional view showing a state in which a sealing coil is incorporated in a small motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing coil 2 Bobbin 3 Coil 4 Sealing material 5 Winding cylinder 6 Flange part 7 Bobbin inner hole 8 Bearing part 9 Thick part 10 Thick part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H02K 3/30-3/52 H02K 5/08

Claims (3)

(57) [Scope of request for utility model registration] 1. A bobbin inner hole is formed inside a cylindrical winding drum, and a flange is integrally formed at both ends of the winding drum, and a coil is wound around the winding drum. In a sealed coil enclosing outer portions of both flange portions with a sealing material, the flange portion starts from the bobbin inner hole, and is formed over the entire circumference along the bobbin inner hole. in has a thick portion of the annular projecting outward, this on the distal end side of the flange portion from the thick portion is thin portion that the sealed by the sealing material is formed thinner than <br/> the thick portion Are formed continuously over the entire circumference of the collar, and the bobbin structure of the sealing coil. 2. The bobbin has an outer surface formed on one side of the bobbin.
In the bobbin structure of the sealed coil having a bearing portion for the output shaft on the tip side from the hole , the flange portion has an annular thick portion starting from the bobbin inner hole and extending up to 1/2 or more of the diameter of the bearing portion. The bobbin structure for a sealed coil according to claim 1, wherein the bobbin structure is formed integrally. 3. The bobbin structure of a sealed coil according to claim 1 , wherein an annular thick portion outside the thick portion is formed at intervals on the flange portion.