JPH08322231A - Coil bobbin for stepping motor - Google Patents

Abstract

PURPOSE: To provide a coil bobbin for stepping motor in which the end section of a winding laid below a connecting terminal block is not caught between the terminal block and peripheral edge section of a stator yoke when the terminal block is put in a notched recessed section 14 when a coil bobbin is housed in a stator yoke and which is prevented from jumping out or floating after the bobbin is housed in the stator yoke. CONSTITUTION: A coil bobbin 20 has two flange sections 22 and 24 formed at both ends of a core section 7 in projecting states. A connecting terminal block 12 is protruded from the periphery of the upper flange section 22 and two projections 28 are provided on the peripheral edge of the lower flange section 24. When the coil bobbin 20 is housed in a stator yoke 6, the two projections 29 are put in a notched recessed section 14, brought into contact with the internal bottom face 14b of the section 14, and elastically bent upward along the internal surface of the section 14b. The terminal block 12 is arranged in the section 14 after the projections 28 are put in the section 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil bobbin of a stepping motor housed in a cup-shaped stator yoke, and more particularly to improvement of the collar shape of the bobbin.

[0002]

2. Description of the Related Art In a general stepping motor, a coil bobbin around which a winding is wound is housed in a cup-shaped stator yoke, and a plate-shaped stator yoke is assembled above the housed coil bobbin so that a motor stator The parts are designed to be composed. FIG. 9 shows a state before assembly with the conventional coil bobbin 2, the cup-shaped stator yoke 6, and the plate-shaped stator yoke 4. At both ends of the winding core portion 7 of the coil bobbin 2, two annular flange portions 8 and 10 having substantially the same shape are formed to project. A connection terminal block 12 is provided so as to project on the peripheral edge of the upper flange portion 8, and a winding end portion 15 extended from the winding winding portion 13 is provided below the connection terminal block 12 and a terminal 9 of the connection terminal block 12. It is connected to the. The coil bobbin 2 configured in this way is
It is incorporated into the cup-shaped stator yoke 6 from the lower flange portion 10 side. At the time of this assembling, the connection terminal block 12 provided on the upper collar portion 8 is arranged inside the notch recess 14 which is partially notched at the peripheral edge portion 6a of the stator yoke 6, and has a plate shape. After the stator yoke 4 is assembled, it is projected from the outer surface of the assembled stator portion.

[0003]

However, since the above assembling work is performed manually, when the coil bobbin 2 is housed in the cup-shaped stator yoke 6, the coil bobbin 2 is axially oriented with respect to the yoke 6. It is difficult to correctly insert the connection terminal block 12 of the coil bobbin 2 into the notch recess 14 of the cup-shaped stator yoke yoke 6 only by moving the.
The procedure is such that the connection terminal block 12 is brought into contact with the peripheral edge portion 6a of the stator yoke 6, and then the coil bobbin 2 is relatively rotated around the axis to perform the alignment. Therefore, the winding end portion 15 below the connection terminal block 12 is sandwiched between the upper surface of the peripheral edge portion 6a and the lower surface of the connection terminal block 12, and when the coil bobbin 2 is relatively rotated in this state, it is scratched. I was sometimes cut off.

On the other hand, in order to facilitate the insertion work, the inner diameter of the cup-shaped stator yoke 6 is formed larger than the outer diameter of the coil bobbin 2 with a margin. Therefore,
After inserting the coil bobbin into the cup-shaped stator yoke 6,
If vibration or impact is applied by the assembly work or the transportation work before the plate-shaped stator yoke 4 is assembled to the cup-shaped stator yoke 6, the coil bobbin 2 may float up or pop out. As a result, the position where the coil bobbin 2 is housed is displaced, the connection terminal base 12 is disengaged from the cutout recess 14, and the upper flange 8 is mounted on the peripheral edge 6a.

The present invention has been made in view of the above circumstances. An object of the present invention is to house a coil bobbin in a stator yoke so that the winding end portion extending below the connection terminal block has a cup-like shape. (EN) A coil bobbin for a stepping motor, which is not sandwiched between the stator yoke and the upper surface of the peripheral edge of the stator yoke and which prevents the coil bobbin from popping out or rising after being housed in a cup-shaped stator yoke. .

[0006]

In order to achieve the above object, in a coil bobbin of a stepping motor according to the present invention, first and second collars are formed so as to project radially outward on both sides of a coil winding core. And a coil bobbin that is provided with a connection terminal block for a winding projecting from the periphery of the first collar portion, the coil bobbin being accommodated in the cup-shaped stator yoke of the stepping motor from the side of the second collar portion. In the coil bobbin of the stepping motor in which the connection terminal block is arranged inside the cutout recess formed in the peripheral edge portion of the stator yoke, the peripheral edge of the second flange portion corresponding to the connection terminal block. An elastically bendable protrusion is provided on the stator yoke, and the protrusion can pass through the inside of the recess when the coil bobbin is housed in the stator yoke. Projecting portion when the deeply inserted into section is characterized by being to be resiliently bent upward along the inner wall surface of the stator yoke.

In particular, the projecting portion is provided with a groove portion formed along the bent portion, or is formed thinner than the wall thickness of the second flange portion.

The coil bobbin is formed of liquid crystal polymer, and the protrusion is integrally formed with the second flange.

Further, an elastically bendable protrusion is formed on the periphery of the second collar portion on the opposite side of the protrusion with the coil core portion sandwiched between the coil bobbin and the stator yoke. The protrusion is elastically bent upward along the inner wall surface of the stator yoke when it is housed in.

[0010]

In the coil bobbin of the stepping motor according to the present invention having the above structure, when the coil bobbin is housed in the cup-shaped stator yoke, the coil bobbin is housed from the second flange side and corresponds to the connection terminal block. Since the protruding portion of the second flange portion provided on the inside of the notch concave portion of the stator yoke passes through, the lower surface of the connection terminal block of the first flange portion is sufficiently spaced from the upper surface of the peripheral edge portion of the stator yoke. The opened state is aligned with the cutout recess, and the coil bobbin is inserted as it is along the axial direction. Further, when the coil bobbin is deeply inserted into the inside of the stator yoke, the protruding portion elastically bent upward along the inner wall surface of the stator yoke,
The coil bobbin is locked in the stator yoke because it abuts against the inner wall surface and presses the inner wall surface.

The groove is formed along the bent portion of the protruding portion or is formed thinner than the wall thickness of the second flange portion, so that the protruding portion is easily bent.

Further, if the protruding portion is integrally formed with the coil bobbin formed of the liquid crystal polymer, the protruding portion can be easily bent.

Further, the coil bobbin is wound around the coil bobbin by elastically bending the protrusion formed on the peripheral edge of the second flange upward along the inner wall surface of the stator yoke, similarly to the protrusion. Since it is locked on the side opposite to the second flange part that sandwiches the part, the coil bobbin can be locked more reliably.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of a coil bobbin for a stepping motor according to the present invention will be described in detail below with reference to the accompanying drawings. The same parts as those of the conventional example will be described with the same reference numerals. FIG. 1 shows a coil bobbin 20 according to this embodiment.
And a plate-shaped stator yoke 4 and a cup-shaped stator yoke 6 that house the same. The coil bobbin 20 is housed in a cup-shaped stator yoke, and a plate-shaped stator yoke is assembled above the housed coil bobbin to form a stator portion of a stepping motor.

In the coil bobbin 20, as in the conventional case, two annular flange portions 22 and 24 are formed at the upper and lower ends of the coil core portion 7 around which the winding is wound. A connection terminal block 12 having two terminals 9 is integrally projectingly formed on the peripheral edge of the upper end flange portion 22. The winding end portion 15 drawn out from the winding winding portion 13 extends below the connection terminal base 12 and is connected to the terminal 9.

In the coil bobbin 20 of this embodiment,
The lower end collar 24 corresponding to the protruding position of the connection terminal block 12
A projecting portion 26 that can be elastically bent upward is formed on the peripheral edge of the.

Here, it is preferable that the protruding portion 26 is integrally formed with the lower end collar portion 24 of the coil bobbin by a synthetic resin such as liquid crystal polymer having high elasticity. The protruding portion 26 of FIG. 1 is composed of two protrusions 28, both of which are located below the connection terminal block 12 of the upper end flange portion 22.
Are arranged at intervals corresponding to the circumferential width of the.

The coil bobbin 20 having these two protrusions 28 is provided in the cup-shaped stator yoke 6 at the lower end flange portion 2.
It is accommodated from the 4th side. The cup-shaped stator yoke 6 is
Similar to the conventional case, the cylindrical housing portion 3 having an open upper end surface.
0 is provided inside, and a notch recess 14 is formed in the peripheral portion 6a from the upper end to the middle of the side wall.
With respect to the cutout width of the cutout recess 14, the two protrusions 28
The arrangement width of is set to be slightly smaller, and the two protrusions 28
Both can simultaneously pass through the inside of the cutout recess 14.

The two protrusions 28 are formed on the coil bobbin 20.
When it is housed in the cup-shaped stator yoke 6, it is aligned with the notch recess 14 and is arranged inside the notch recess 14 as shown in FIG. At this time, the connection terminal block 1
With a sufficient gap between the lower surface of 2 and the upper surface of the peripheral portion 6a of the cup-shaped stator yoke, the notch recess 1
Aligned above 4.

After that, the two protrusions 28 are cut into the cutout recesses 1.
When the coil bobbin 20 is moved along the axial direction of the cup-shaped stator yoke 6 so as to pass through the inside of 4,
Even if the rotational biasing force acts on the coil bobbin 20,
The rotation of the coil bobbin 20 is restricted because the two protrusions 28 come into contact with the inner surface 14 a of the cutout recess 14. As a result, the connection terminal block 1 located above the cutout recess 14 is
The 2 is accurately guided into the recess 14. When the coil bobbin 20 is inserted further deeply after the pole tooth group 32 formed upright on the inner bottom surface of the accommodating portion 30 is inserted inside the winding core portion 7, the two protrusions 28 are cut into the cutout recesses 14 respectively. Is brought into contact with the inner bottom surface 14b of the.

Here, since the two protrusions 28 are elastically bendable, each protrusion 28 is elastically deformed without being divided from the peripheral edge of the lower end flange portion 24 as shown in FIG. Then, it is bent upward along the inner wall surface 6b of the cup-shaped stator yoke 6. Two bent projections 28
Presses the inner wall surface 6b of the housing portion 30 by the elastic force, so that the coil bobbin 20 is held between the pole tooth group 32 and the inner wall 6c of the cup-shaped stator yoke 6. In this state, the coil bobbin 20 is further inserted along the axial direction of the cup-shaped stator yoke 6, so that the connection terminal block 12 is inserted into the notch recess 14 in a state of being aligned and arranged inside thereof. It As shown in FIG. 4, the coil bobbin 20 accommodated in the bottom of the accommodating portion 30 is clamped by the pressing of the two protrusions 28 and locked in the cup-shaped stator yoke 6. Thereafter, the plate-shaped stator yoke 4 is disposed above the coil bobbin 20 to complete the assembly of the stator.

As described above, when the coil bobbin 20 is housed, the two protrusions 28 provided on the peripheral edge of the lower end flange portion 24 corresponding to the connection terminal block 12 are provided with the cutout recesses 14 of the cup-shaped stator yoke 6. The connection terminal block 12 of the upper end flange portion 22 is positioned above the cutout recessed portion 14 with a sufficient distance from the peripheral edge portion 6a of the plate-shaped stator yoke 6 by being inserted into and passing through the inside thereof. Then, the coil bobbin is inserted as it is along the axial direction of the cup-shaped stator yoke and guided to the notch recess 14. Therefore, as in the conventional case, the connection terminal block 12
Since the winding end portion 15 is not sandwiched between the peripheral edge portion 6a and the connection terminal block 12 in arranging,
It is possible to prevent the winding end portion 15 from being scratched or cut.

When the coil bobbin 20 is inserted further deeply, the two protrusions 28 are elastically bent upward along the inner wall surface 6a of the accommodating portion 30 to abut against the inner wall surface 6b and press the inner wall surface 6b. Therefore, the coil bobbin 20 has the inner wall 6
It is held between c and the pole tooth group 32, and is locked in the lower stator yoke 6 at the same time as it is housed. This can prevent the coil bobbin 20 from rising or popping out from the cup-shaped stator yoke 6 before the upper stator yoke 4 is arranged. From these things, simply by adding a simple configuration of the protrusion 26,
It is possible to prevent the coil bobbin from rising and popping out, and the labor at the time of accommodation can be reduced to improve workability and reliability of the stator portion.

The protrusion 26 is shown in FIG.
If devised as shown in (a) and (b), the lower end flange portion 2
It is possible to make it bendable without using the thin-wall formation of No. 4 or the liquid crystal polymer molding. That is, as shown in FIG. 5A, for example, if a groove portion 34 having a V-shaped cross section is formed on the lower surface of the protruding portion 26, the groove portion 34 is easily bent along the groove portion 34. In addition, as shown in FIG.
If 6 is formed thinner than the lower end flange 24, the protrusion 26
It is easily bent along the stepped portion 36 formed at the boundary between the lower end flange 24 and the lower end. The groove 34 may be formed not only on the lower surface of the lower end flange 24 but also on the upper surface thereof.

Further, as the lower collar portion 24, as shown in FIG.
Some have other external shapes as shown in (a) to (c). The protrusion 26 may be formed of two protrusions 28, or a wide single protrusion 38 as shown in FIG. 6A. In addition, the protruding portion 2 is provided on the lower end collar portion 24 of FIGS. 6B and 6C.
6 and 38, a protrusion 40 is provided on the peripheral edge of the lower end flange 24 such that it is located on the opposite side of the protrusions 26 and 38 with the winding core 7 interposed therebetween. The protrusion 40 includes the protrusion 26,
Similar to 38, when the coil bobbin 20 is housed, the coil bobbin 20 is elastically bent upward along the inner wall surface 6b of the lower stator yoke 6, so that the coil bobbin 20 can be reliably locked. In addition, if the number of the protrusions 40 is large, the coil bobbin can be locked more reliably.

7 and 8, the coil bobbin 2 is provided inside one cup-shaped outer yoke member 42 having a deep bottom.
It shows a case where two 0s are stacked one above the other and accommodated. A notch recess 46 having a deep bottom is formed in the peripheral edge portion 43 of the cup-shaped outer yoke member 42. The lower end collar portions 24a, 2 of the coil bobbins 20a, 20b used here
On the periphery of 4b, projecting portions 26a, which are provided corresponding to the connection terminal blocks 12a, 12b of the upper end flange portions 22a, 22b,
26b and projections 40a, 40b provided on the opposite side of the projections 26a, 26b, respectively. These two coil bobbins 20a, 20b are housed inside the cup-shaped outer yoke member 42, with the upper and lower sides sandwiched by the two inner yoke members 44a, 44b, respectively. First, the coil bobbin 20a to be housed first
Similarly to the above, by inserting the protrusion 26a into the notch recess 46 of the outer yoke member 42, the connection terminal block 12a is aligned with a sufficient distance from the upper surface of the peripheral portion 43 of the outer yoke member 42, The coil bobbin 20a is inserted as it is along the axial direction. Further, by inserting the coil bobbin 20a deeply, the protrusion 26a
Is elastically bent upward along the inner wall surface 45 of the outer yoke member 42, and the coil bobbin 20 is locked in the outer yoke member 42. In addition, the protrusion 40a of the coil bobbin 20a
Also, since the coil bobbin 20 is elastically bent upward along the inner wall surface 45 of the outer yoke member 42 similarly to the projecting portion 26a, the coil bobbin 20 is more reliably locked in the outer yoke member 42. As for the coil bobbin 20b to be housed next,
The projecting portion 26b of the lower end flange portion 24b is inserted into the notch recess 46, and the lower surface of the connecting terminal block 12b of the upper end flange portion 22b is aligned with a sufficient distance from the upper surface of the peripheral edge portion 43 of the outer yoke member 43. . Although the protrusion 26b of the coil bobbin 20b is not bent, the protrusion 40b is bent, so that the coil bobbin 20b can be locked in the outer yoke member 42. FIG. 8 shows a state in which the pair of coil bobbins 20a and 20b held by the inner yoke members 44a and 44b are housed in the deep cup-shaped outer yoke member 42.

[0027]

As described in the above embodiments, according to the coil bobbin of the stepping motor according to the present invention, the lower surface of the connecting terminal block of the collar portion is sufficiently spaced from the upper surface of the peripheral portion of the stator yoke. Since it is positioned inside the notch recess by aligning with, the winding end does not get pinched between the peripheral edge even when the winding end extends below the connection terminal block, and the winding end does not get caught. The part can be prevented from being scratched or cut. Further, since the coil bobbin is locked in the stator yoke at the same time as it is housed by bending the projecting portion upward along the inner wall surface of the cup-shaped stator yoke, it is possible to prevent the coil bobbin from rising or popping out after housing.

When the groove is formed along the bent portion of the protruding portion or when the protruding portion itself is formed thinner than the flange portion, the protruding portion can be easily bent. Even if the material is hard and difficult to bend, it can be sufficiently bent by the force of a human hand.

When the coil bobbin is formed of liquid crystal polymer, the protrusion is formed integrally with the collar, so that the protrusion can be easily bent by the force of a human hand or the like.

Further, when a protrusion is formed on the peripheral edge of the flange on the opposite side with the protrusion and the coil winding core sandwiched, the coil bobbin is more surely cup-shaped due to the elastic bending by the protrusion. It is locked in the stator yoke.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a coil bobbin and a stator yoke of a stepping motor according to the present invention.

FIG. 2 is a vertical cross-sectional view showing a state immediately before housing a coil bobbin in a cup-shaped stator yoke.

FIG. 3 is a vertical cross-sectional view showing a state in which a coil bobbin is partially accommodated in a cup-shaped stator yoke.

FIG. 4 is a vertical cross-sectional view showing a state in which a coil bobbin is completely housed in a cup-shaped stator yoke.

FIG. 5A is an enlarged vertical sectional view showing another embodiment of the protruding portion of the coil bobbin. (B) It is the longitudinal cross-sectional view which expanded and showed other Example of the protrusion part of a coil bobbin.

FIG. 6A is an end view showing another embodiment of the protrusion formed on the lower end flange of the coil bobbin. (B) It is an end view which showed the protrusion part of FIG. 1 formed in the lower end collar part of a coil bobbin, and another protrusion part. FIG. 7C is an end view showing the protrusion of FIG. 6A and another protrusion formed on the lower end flange of the coil bobbin.

FIG. 7 is an exploded perspective view showing a coil bobbin accommodated in a deep cup-shaped stator yoke.

FIG. 8 is a vertical cross-sectional view showing two coil bobbins housed in the stator yoke of FIG.

FIG. 9 is a perspective view showing a conventional example of a coil bobbin and a stator yoke.

[Explanation of symbols]

2 coil bobbin 4 plate-shaped stator yoke 6 cup-shaped stator yoke 6a peripheral portion 6b inner wall surface 6c inner wall 7 core portion (coil core portion) 8 collar portion 9 terminal 10 collar portion 12 connection terminal block 13 winding winding portion 14 Notch Recesses 14a Inner Side Surface 14b Inner Bottom 15 Winding End (Winding) 20 Coil Bobbin 22 Upper End Collar Part (First Collar Part) 24 Lower End Collar Part (Second Collar Part) 26 Projection Part 28 Projection 30 Storage Part 32 pole tooth group 34 groove part 36 step part 38 projecting part 40 projecting part 42 outer yoke member 43 peripheral part 45 inner wall surface 44 inner yoke member 46 notch concave part

Claims (4)

[Claims] 1. A first and second flange portions (22, 22) formed to project radially outward on both sides of a coil winding core portion (7).
A coil bobbin (20) provided with a connecting terminal block (12) for a winding (15) projecting from the periphery of the first collar portion (22), which is a cup-shaped stator of a stepping motor. A cutout recess (14) housed in the yoke (6) from the side of the second flange portion (24) so that the connection terminal block (12) is formed in the peripheral edge portion (6a) of the stator yoke (6).
In a coil bobbin of a stepping motor which is arranged on the inside of, a resiliently bendable protrusion (26) is provided on the peripheral edge of the second flange (24) corresponding to the connection terminal block (12). The protrusion (26) can pass through the inside of the cutout recess (14) when the coil bobbin (20) is housed in the stator yoke (6), and the coil bobbin (20) can be passed through the stator yoke. Stepping, characterized in that the protrusion (26) is elastically bent upward along the inner wall surface (6b) of the stator yoke (6) when deeply inserted into the inside of (6). Motor coil bobbin. 2. The protrusion (26) has a groove (34) formed along a bent portion, or is formed thinner than the thickness of the second flange (24). The coil bobbin of the stepping motor according to claim 1, wherein: 3. The coil bobbin (20) is molded from a liquid crystal polymer, and the protrusion (26) is integrally formed with the second collar (24). A coil bobbin of the stepping motor according to 2. 4. The second flange (2) is located on the opposite side of the protrusion (26) with the coil winding core (7) interposed therebetween.
4) An elastically bendable protrusion (40) is formed on the periphery of the stator yoke (6) when the coil bobbin (20) is housed in the stator yoke (6). 4. The elastically bent upwards along the inner wall surface (6b) of the blade, according to any one of claims 1, 2 and 3.
A coil bobbin of the stepping motor according to the item.