JPH0677206U - Thin coil - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the solder wettability of electrodes and improve the reliability of solder connection. A coil formed by winding a metal foil 1 having an insulating layer 4 coated on the surface of a conductor layer 2 and cutting the metal foil 1 into a predetermined thickness. A plating layer 3 made of a metal having solder wettability is formed therebetween. [Effect] The plated layer having good solder wettability is exposed on the electrode, so that the electrode can be reliably soldered to the connection piece or the like of the metal pattern, and the reliability of conduction can be improved. Further, it is not necessary to perform a special treatment on the electrode to improve the solder wettability, and the manufacturing cost can be reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a thin coil arranged in a stator of a flat facing type brushless motor, for example.

[0002]

[Prior art]

 This type of thin coil is arranged, for example, in a two-phase or three-phase configuration on the stator substrate of a flat-opposed brushless motor, and is excited by energizing each thin coil with a predetermined phase current to generate a thin coil. The drive magnet of the rotor, which faces the coil in a plane, is rotationally biased.

A part A of FIG. 2 shows a metal foil 10 for obtaining a thin coil. The metal foil 10 is a wide conductor layer 11 made of a copper foil or an aluminum foil and is laminated on one surface side of the conductor layer 11. It is composed of a layered insulating layer 12 made of resin such as poly-amide-imide. The insulating layer 12 may be laminated on both sides of the conductor layer 11 as shown in part B of FIG. On the other hand, an adhesive is applied to the surface of the metal foil 10, and the metal foil 10 is wound around a predetermined core a predetermined number of times with the interposition of the adhesive, and the metal foils 10 are bonded to each other in layers. Thereby, the wound body 13 as shown in FIG. 2 is formed.

After winding the winding core 13, the winding body 13 is cut into a thin slice with a predetermined thickness using a multi-wire saw, a band saw, or the like to form a thin coil 15 as shown in FIG. Electrodes 16 and 17 are formed at the winding start and the winding end of the outer peripheral surface of the thin coil 15 thus formed, respectively. These electrodes 16 and 17 are formed by peeling the insulating layer 12 at the front end portion of the metal foil 10 to form the electrode 16 on the inner peripheral side in a pre-process of winding the metal foil 10, and the metal foil 10 is formed a predetermined number of times. After winding, the rear end portion is peeled off to form the electrode 17 on the outer peripheral side. As shown in FIG. 5, these electrodes 16 and 17 are formed by pressing the electrode peeling jig 30 against the metal foil 10 for curling, and scraping off the top insulating layer 12 with a paper file or the like.

The electrodes 16 and 17 are respectively disposed on the holding substrate 18 shown in FIG. 4 and soldered to the connection pieces 21 and 22. That is, the holding substrate 18 is composed of a coil holder 19 made of resin and a metal pattern (not shown), and the coil holder 19 is provided with a plurality of coil-shaped insertion portions 20. Further, on the back surface side of the coil holder 19, a metal pattern plate formed in a connection pattern shape is integrally insert-molded in order to connect the thin coil 15 in a two-phase or three-phase form. The metal pattern plate is formed by pressing a thin conductive plate to form the connecting pieces 21 and 22 and to lead the plurality of terminals 23 side by side to the outside. The connection pieces 21 and 22 are exposed in the insertion part 20 of the coil holder 19, and after inserting the thin coil 15 into the insertion part 20 and fixing them by an adhesive, the connection pieces 21 and 22 are connected to the connection pieces 21 and 22. 21 and 22 are connected by soldering.

[0006]

[Problems to be solved by the device]

 However, as described above, the thin coil is formed by using a copper or aluminum foil as a conductor layer and laminating an insulating layer on the surface thereof, and the electrodes are formed by peeling the insulating layer. The copper or the like of the conductor layer exposed at the electrode portion is attacked by oxidation or the like. As a result, the electrode has poor solder wettability, cannot be soldered when it is soldered to the above-mentioned connecting piece, and there is a problem that conduction failure occurs between the electrode and the connecting piece, resulting in a decrease in reliability. .

The present invention has been made in order to solve such a problem, and an object thereof is to provide a thin coil capable of improving the solder wettability of electrodes and enhancing the reliability of solder connection. And

[0008]

[Means for Solving the Problems]

 The present invention is a coil formed by winding a metal foil having an insulating layer coated on the surface of a conductor layer and cutting the metal foil to a predetermined thickness. The coil is soldered between the conductor layer and the insulating layer. It is characterized in that a plating layer made of a metal having wettability is formed.

[0009]

[Action]

 If a plating layer made of a metal having solder wettability is formed between the conductor layer of the metal foil and the insulating layer, when the electrode is formed by peeling off the insulating layer, a plating layer with good solder wettability appears. The soldering of the metal pattern to the connection piece or the like becomes reliable, and the reliability of conduction between the two is improved. In addition, the thin coil does not need to be subjected to a special treatment on the electrode, which reduces the cost.

[0010]

【Example】

 An embodiment of a thin coil according to the present invention will be described below with reference to the drawings. The same parts as those shown in FIGS. 2 to 5 are designated by the same reference numerals, and detailed description thereof will be omitted. The thin coil according to the present invention shown in FIG. 1 is different from the thin coil described above in that a plating layer made of a metal having solder wettability is formed between the conductor layer and the insulating layer of the metal foil. .

That is, the metal foil 1 has a plating layer 3 formed by plating metal with tin on one surface of a wide conductor layer 2 made of copper foil or aluminum foil. The tin used in this mack is generally suitable as a metal having good solder wettability when soldering, and also has a property of being less likely to be oxidized than copper of the conductor layer 2. Other than tin, gold, silver, nickel, and the like are examples of metals of this type having good solder wettability, and these metals also have the property of being difficult to oxidize. Also, other metals can be used as long as they have the above properties.

Further, an insulating layer 4 made of a resin such as poly-amide-imide is laminated on the surface of the plating layer 3 as in the above-mentioned example. Furthermore, an adhesive is applied to the surface of the metal foil 1, and the metal foil 1 is wound around a predetermined winding core a predetermined number of times, and the metal foils 1 are adhered to each other in a layered manner to form a winding as shown in FIG. The revolving body 5 is formed.

After winding the winding core 5, the winding core 5 is cut into a thin slice with a predetermined thickness using a multi-wire saw, a band saw, or the like to form a thin coil 15 similar to that shown in FIG. Then, the electrodes 16 and 17 formed at the winding start of the inner peripheral surface and the winding end of the outer peripheral surface of the thin coil 15 are formed by peeling off the insulating layer 4 as in the above-mentioned example. When the insulating layer 4 is peeled off, the plated layer 3 is exposed, and this portion is formed as the electrodes 16 and 17.

However, since the plating layer 3 is thin, when the insulating layer 12 is scraped off with a file or the like when forming the electrodes 16 and 17, the plating layer 3 may also be scraped off. . Therefore, as shown in FIG. 5, it is desirable that the electrode peeling jig 30 is pressed against the metal foil 1 and is bent, and the insulating layer 4 on the top thereof is dissolved and removed by a solvent. As this solvent, N-methyl-2-pyrrolidone or the like is suitable. When the electrodes are formed by melting as described above, the plating layer 3 can be left and the initial purpose can be easily achieved.

The thin coil 15 formed as described above is inserted into the insertion portion 20 of the coil holder 19 and fixed by adhesion as described above, and the electrodes 16, 17 of the thin coil 15 are connected to the connection piece 21, 22 is soldered and connected. Since the plating layer 3 having good solder wettability is exposed at the electrodes 16 and 17 during this soldering, reliable soldering can be performed.

It should be noted that the above-mentioned embodiment shows an example, and the shape of the thin coil is not limited to the above-mentioned example, and may be formed in a substantially triangular shape or the like. In addition, since the conductor layers are exposed on both end faces of the thin coil, insulation treatment may be performed by separately applying an insulating paint or the like, and various modifications can be made without departing from the gist of the present invention. .

[0017]

[Effect of device]

 As is clear from the above description, according to the thin coil according to the present invention, the plating layer made of the metal having solder wettability is formed between the conductor layer and the insulating layer of the metal foil, so that the electrode is formed on the electrode. The plating layer having good solder wettability is exposed, and soldering with a connecting piece of a metal pattern or the like can be reliably performed, so that reliability of conduction can be improved. In addition, there is an advantage that the electrode does not need to be subjected to a special treatment for improving solder wettability, and the manufacturing cost can be reduced.

[0018]

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a thin coil according to the present invention.

FIG. 2 is a perspective view showing a conventional thin coil.

FIG. 3 is a perspective view showing a thin coil.

FIG. 4 is a plan view showing an example of a holding substrate that holds a thin coil.

FIG. 5 is an explanatory view showing a means for forming electrodes.

[Explanation of symbols]

 1 Metal foil 2 Conductor layer 3 Plating layer 4 Insulating layer 15 Thin coil 16,17 Electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taiji Matsuyama 14-888 Ako, Komagane-shi, Nagano Sankyo Seiki Co., Ltd. Komagane factory

Claims (1)

[Scope of utility model registration request] 1. A coil formed by winding a metal foil having an insulating layer coated on the surface of a conductor layer and cutting the metal foil to a predetermined thickness, the coil being formed between the conductor layer and the insulating layer. A thin coil formed by forming a plating layer made of a metal having solder wettability.