JPS61196743A - Coil bobbin for electric machine - Google Patents

Abstract

PURPOSE:To enable coils wire to be wound up in a well-ordered form without leaving space between coils and ring corner sections, by forming a step section extending on the full periphery integrally in the ring corner section on the winding start side of the coils on a coil bobbin. CONSTITUTION:On a coil bobbin 1 consisting of a cylindrical shell section 1a and a ring flange section 1b, a step section 5 is formed in the ring corner section between the shell section 1a and the flange section 1b. The step section 5 is set so that the salient height h in the radial direction may be equal to the wire diameter of coil wires 2. The width W in the axial direction is contrived to be set so that it may be smaller at a winding start position 1d-S and may be almost equal to the coil wire diameter at a winding end position 1d-e. In this manner, a space between the first layer of the coil wires 2 and the flange 1b is avoided, an so the second layer and the following layers can be also wound up in well-ordered form with coil wires.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a coil bobbin for an electric machine such as an alternating current generator for an automobile.

[Summary of the invention]

In a coil bobbin for electrical machinery, an annular corner formed between a flange on the winding start side of the coil and a cylindrical body has a protruding height equal to the coil wire diameter, and a first winding of the coil. By providing a stepped portion extending substantially over the entire circumference from the winding end position to the winding start position and protruding radially outward from the outer peripheral surface of the bobbin body, the bobbin flange on the coil winding start side and the coil This prevents a gap from forming between the first winding and the first winding.

[Conventional technology]

FIG. 3 shows a conventional method of winding a coil wire 2 around a coil bobbin 1 to form a rotor coil for an automotive alternator. In this case, the bobbin 1 is made of synthetic resin, and has a cylindrical body part 1a and annular flange parts 1b and 1c that extend outward in the radial direction from both ends of the body part 1a. A lead groove 1d for receiving the lead portion of the coil is formed on the axially inner surface of the portion 1b in a substantially tangential direction from the outer peripheral edge of the flange portion 1b to the outer peripheral surface of the body portion 1a. A T-shaped lead terminal 1e is provided protruding from the outer peripheral edge of the flange portion 1b at a position aligned with the outer end of the flange portion 1d.

The work of winding the coil wire 2 around the bobbin 1 is to wrap the tip 2a of the lead portion of the coil wire around the lead terminal 1e two to three times and temporarily secure it, and then wind the coil wire portion following this tip 2a onto the bobbin 1. The bobbin 1 is extended along the lead groove 1d to the body 1a, and in this state, the bobbin 1 is mounted on the rotary spindle 3 as shown in the figure, and the spindle 3 is rotated in the direction of the arrow in FIG. In this case, the trunk 1
During the formation of the first layer of coil that is in direct contact with a, the coil feeder 4 is moved in the axial direction of the bobbin 1 as shown by the arrow, and the winding work is performed while feeding the coil wire in the same direction. As a result, each winding (turn) of the coil is formed and arranged in close contact with each other and aligned. That is, the amount of movement of the coil feeder 4 in the axial direction during one rotation of the bobbin 1, that is, the pitch of the coil, is equal to the wire diameter of the coil wire 2. In addition, in FIG. 3, the coil pitch is illustrated in a large scale for easy understanding.

When the formation of the first layer of coils is completed, the coil feeder 4 is then moved in the direction opposite to the arrow, that is, toward the winding start side flange portion 1b, and thereby,
The windings of the second layer are sequentially formed in close contact with each other,
Thereafter, the third layer, fourth layer, etc. are formed in sequence.

[Problem that the invention seeks to solve]

The first winding of the first layer and the winding start side flange part 1b
A gap g extending in the circumferential direction of the bobbin 1 is created between the
The width of this gap is zero at the winding start position of the first winding, and gradually increases from that position to the winding end position of the first winding, and at this winding end position, the wire diameter of the coil wire is equal to FIG. 4 is a perspective view showing how the gap Q occurs, and FIG. 5 shows the gap g clearly by cutting the bobbin 1 in the axial direction. In addition, the arrow in FIG. 5 indicates the coil wire 2 during the coil winding operation.
, i.e., the direction in which each layer of the coil is formed. As is clear from Fig. 5, the final turn of the second layer of the coil falls into the gap Q, and as a result, the turns of the third and subsequent layers are also irregularly wound, resulting in the completed coil. The ampere-turns (A, T) of the circuit decrease, resulting in a decrease in output.

Means for Solving Problem C] In the coil bobbin according to the present invention, the first winding of the coil is formed in the annular corner formed between the flange part on the winding start side of the coil and the body part. A stepped portion extending over the entire circumference from the end position to the winding start position is provided and protrudes radially outward from the outer circumferential surface of the body, and the height of this protrusion of the stepped portion, that is, from the outer circumferential surface of the body. The radial protrusion dimension of is equal to the wire diameter of the coil, and the width of the stepped portion in the axial direction of the bobbin is equal to the wire diameter of the coil at the end position of the first winding of the coil, and The diameter of the coil wire is narrower at a portion closer to the winding start position, and furthermore, the corner of the stepped portion on the side opposite to the winding start side flange portion is rounded.

[Effect]

The stepped portion prevents a gap from forming between the first winding of the first layer coil, that is, the first winding, and a part of the winding start side flange = 6 of the bobbin, so that the second and subsequent layers During the winding operation, aligned winding of each turn is achieved.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS. 1 and 2. In these figures, the same parts as in the conventional structure shown in FIGS. 3 to 5 are designated by the same reference numerals.

A coil bobbin 1 shown in FIGS. 1 and 2 is integrally molded from a synthetic resin such as nylon, and is used as a bobbin for a rotor coil of an automotive alternator. A stepped portion 5 is integrally formed with the bobbin 1 at an annular corner formed between the annular flange portion 1b on the coil winding start side of the coil bobbin 1 and the cylindrical body portion 1a. This stepped portion 5 extends from the − side edge 1d-8 of the width of the lead groove 1d (circumferential dimension of the body portion 1a) at the meeting portion of the lead groove 1d and the outer circumferential surface of the body portion 1a. The lead groove 1d extends approximately once around the outer peripheral surface to the other end 1d-8 of the width of the lead groove 1d.

The start of winding the coil wire is at the negative end 1 of the width of the lead groove 1d.
Since it starts from d-3, this negative end is called the "coil winding start position." The first winding (first turn) of the first layer coil is at this "coil winding start position J1d-s"
Starting from , go around the body 1a of bobbin 1, and
Geometrically, these two positions exist on a single (same) point on the circumference, but in this application, for convenience, the "winding end position" is [ It is assumed that the winding start position J1d is the position immediately before -s. In the illustrated embodiment, the "winding end position" is assumed to be the position of the other end 1d-e of the width of the lead groove 1d.

Therefore, in the illustrated embodiment, the step 5 is the first part of the coil.
Winding end position 1d-e to winding start position 1d-8
It can be said that it extends in the circumferential direction along the outer periphery of the body portion 1a until the end.

The stepped portion 5 protrudes outward in the radial direction from the outer peripheral surface of the body portion 1a of the bobbin 1, and the height of this protrusion is hl.
That is, the protrusion dimension of the bobbin in the radial direction is equal to the wire diameter of the coil.

The width W1 of the stepped portion 5, that is, the dimension in the axial direction of the bobbin 1, is equal to the wire diameter of the coil at the winding end position 1d-e of the first winding of the coil, and from this winding end position 1d-e to the winding start position 1d. -s, it becomes narrower gradually from the area immediately near the winding start position 1d-e to the winding start position Id-e, and becomes zero (0) at the winding start position. ing. The slope of this portion is selected to closely match the bend c between the portion of the coil wire of the first turn of the coil and the portion of the coil wire within the lead groove 1d.

When looking at the stepped portion 5 in the axial cross section of the bobbin 1, one side of the stepped portion 5 is integral with the flange portion 1b of the coil on the winding start side, and the bottom portion is integral with the body portion 1a of the bobbin. A corner portion on the opposite side from the flange portion 1b is rounded to a radius equal to half the coil wire diameter. With this configuration, the stepped portion 5 prevents the enamel coating of the coil wire from being damaged during winding work, and allows the coil wire of the first turn of the coil to be moved away from the flange portion 1b on the winding start side while moving the bobbin 1. body part 1
guide it smoothly onto the outer peripheral surface of a.

With the above-described configuration, the first turn of the first layer of the coil is formed along the stepped portion 5, and a conventional bobbin is used between this first turn and the flange portion 1b on the winding start side. The gap 9 that would otherwise exist does not occur.

In addition, since the width W of the stepped portion at the winding end position 1d-e of the first winding is equal to the wire diameter of the coil, this winding end position 1d-e is equal to the wire diameter of the coil.
d-f! In the case of smell, the coil wire is fed in the axial direction by one pitch, and the second and subsequent turns smoothly follow the first turn.

"Also, since the protruding height h of the stepped portion 5 is equal to the wire diameter of the coil, the outer surface (peripheral surface) of the first layer of the coil and the stepped portion 5
The outer circumferential surface of the cylindrical surface is included within the same two cylindrical surfaces. Therefore, as shown in FIG. 2, the final turn of the second layer of the coil is formed on the stepped portion 5, so that all the turns of the second layer are arranged in an orderly manner, and as a result, The windings of the third layer are also formed in an aligned state.

In the above, a case has been described in which the present invention is applied to the coil bobbin 1 of the type in which the lead groove 10 is formed on the side surface of the flange portion 1b on the winding start side. It will be obvious to those skilled in the art that the present invention can also be applied to a type of device (not shown). In addition, the material of the bobbin is not limited to synthetic resin.
It can be made of metal.

〔effect〕

According to the coil bobbin of the present invention, since the windings of the second and subsequent layers of the coil are formed in an orderly manner, a decrease in ampere/turn of the coil due to irregular winding that occurs in conventional bobbins is prevented, and therefore, the coil bobbin of the present invention contributes to increasing the output of the coil.

[Brief explanation of the drawing]

Fig. 1 is an enlarged perspective view of the main part of a coil bobbin according to an embodiment of the present invention, and Fig. 2 is an axial cross-sectional view of the main part, showing a state in which the coil wire is wound in contact with the stepped part. Fig. 3 is a perspective view showing the structure of a conventional coil bobbin and a method of winding a coil wire thereon, and Fig. 4 is a perspective view showing the structure of a conventional coil bobbin and a method of winding a coil wire thereon. 1 in between
Fig. 5 is an enlarged axial sectional view of the main part of the bobbin in Fig. 3;
FIG. 4 is a diagram clearly showing the gap in FIG. 4; 1... Bobbin, 1a... Chest, 1b... Flange part on the winding start side, 1d... Lead groove, 1d-s... Coil winding start position, 1d-e...
Winding end position of the coil, 2...Coil wire, 5...Step part, h...Height of raised part of step part, W...Width of step part.

Claims (1)

[Scope of Claims] A coil bobbin for an electric machine having a cylindrical body and an annular flange extending radially outward from both ends of the bobbin, which is formed between the flange on the winding start side of the coil and the body. A stepped portion extending all around the circumference from the winding end position to the winding start position of the first winding of the coil is formed integrally with the flange part on the winding start side and the body part at the annular corner part of the coil. The height of this protrusion of the stepped portion, that is, the radial protrusion dimension from the outer circumferential surface of the body portion is equal to the wire diameter of the coil,
Further, the width of the stepped portion in the axial direction of the bobbin is equal to the wire diameter of the coil at the winding end position of the first winding of the coil, and is smaller than the coil wire diameter at a portion closer to the winding start position than the winding end position. The coil bobbin for an electric appliance is further characterized in that a corner portion of the stepped portion on a side opposite to the winding start side flange portion is rounded.