JP2005209842A - Shaping method and device of electromagnetic coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve coil shaping method and device such that an electromagnetic coil can be shaped with high dimensional and shape accuracy without damaging the insulation coating of a coil wire. <P>SOLUTION: In the method of shaping a coil by stopping a coil wire (insulation coated wire) 11 fed out from a bobbin at a shaping jig 17 and then turning and feeding the shaping jig to wind the wire around the circumferential surface of a core metal 18, a direct driven press tool 24 is provided on the side of the shaping jig oppositely to the circumferential surface of the core metal. In the last stroke (a range α of about 30° to the end of last turn of the coil) of coil shaping process for winding the wire around the core metal by turning and feeding the shaping jig, the press tool 24 is operated to advance from a retreat position in order to press the end part of the wire forcibly against the circumferential surface of a core metal and to draw the wire thus shaping the coil such that the curvature at the coil end part conforms to the circumferential surface of the core metal. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for forming an electromagnetic coil applied to a tripping trip coil equipped in a circuit breaker such as a distribution breaker or a leakage breaker.

First, as an application example of an electromagnetic coil that is a subject of the present invention, a configuration of a head circuit breaker is shown in FIG. In the figure, 1 is a circuit breaker case, 2 is a stationary contact, 3 is a movable contact, 4 is an opening / closing mechanism, 5 is an opening / closing operation handle, and 6 is a trip coil unit for overcurrent tripping. 6 is an assembly of an electromagnetic coil (air core coil) 7, a coil iron core (dashpot) 8 fitted into the coil 7, a yoke 9, and a swinging armature (operating piece) 10. The operating piece 10 is connected to a latch (tripping mechanism) of the opening / closing mechanism 4, and the electromagnetic coil 7 is connected to the main circuit so as to pass current.
The operation of such a circuit breaker is well known, and when an overcurrent flows in the main circuit due to a short circuit accident of the load, etc. in a state where the circuit breaker is connected to the power supply circuit, the trip coil unit The magnetomotive force of the electromagnetic coil 7 of 6 increases and the armature 10 is attracted. The movement is detected and the opening / closing mechanism 4 trips to open the movable contact 3 and cut off the current.

  Here, the electromagnetic coil 7 is manufactured by spirally winding an insulation coated electric wire having a wire diameter of, for example, φ0.3 mm to φ5 mm, and the coil shape is shown in FIG. (A) to (c). That is, FIG. 3A is an outline drawing of the completed coil component, and the lead portions 7b and 7c are drawn up and down from both ends (winding start side and winding end side) of the coil body portion (coil winding portion) 7a. The coil body portion 7a is covered with a wire (round copper wire) 7d with an insulation coating 7e, and the lead portions 7b and 7c are peeled off the insulation coating 7e to expose the wire 7d. These members (terminals or main circuit conductors) are brazed (or soldered). In order to manufacture this electromagnetic coil 7, first, after winding the wire into the shape shown in FIGS. 3B and 3C, lead portions 7b and 7c extending linearly from both ends of the coil body portion are formed. The coil shape shown in FIG. 3A is obtained by bending in the vertical direction. The trip coil unit 6 is configured by combining the electromagnetic coil 7 with the components of the coil core 8, the yoke 9, and the armature 10 described in FIG.

Further, for the electromagnetic coil 7, the tripping operation characteristics of the trip coil unit 6 shown in FIG. 2 are stabilized, and the assembly of the unit (usually including the trip coil unit 6, the circuit breaker is an assembly robot). High dimensions and molding accuracy are required. That is, the dimensional accuracy for the height h of the coil body portion 7a, the coil pitch p, the radius of curvature r of the coil, and the opening angle θ between the both end leads 7b and 7c shown in FIG. The coil height h is required to satisfy ± 0.3 mm with respect to the design specified dimension, and the lead opening angle ∂ satisfies ± 0.3 °.
On the other hand, various forming methods have been known as mass production methods for electromagnetic coils. As an example, a wire core (spindle shaft) for winding the tip of an insulated coated wire drawn from a wire bobbin is provided. A coil forming apparatus is known in which a coil is formed by winding and holding a wire rod around the peripheral surface of the mandrel after rotating and feeding the forming jig with a servo motor after being locked and held by a forming jig. (For example, see Patent Document 1 and Patent Document 2).

Next, a conventional coil forming apparatus for producing the electromagnetic coil of FIG. 3 by adopting a method of forming a coil by winding a wire rod around the peripheral surface of the core metal in the same manner as disclosed in Patent Documents 1 and 2. This will be described with reference to FIGS. 4A and 4B are diagrams schematically showing a coil forming apparatus, in which 11 is a coil wire (insulation-coated electric wire), 12 is a bobbin wound with a wire (wire supply source), 13 Is a correcting part of the wire 11 (correcting the curl to make it straight), 14 is an insulation peeling part, 15 is a wire feeding part, and 16 is a coil forming part.
Here, the coil forming unit 16 includes a forming jig 17 whose detailed structure will be described later, a rotary servo motor 20 that mounts the forming jig 17 downward and rotates and feeds it, and an upper and lower servo motor 21. A nozzle-shaped supply guide 22 and a cutter 23 for cutting the wire 11 are provided on the end side. Further, as shown in FIGS. 5 (a) and 5 (b), the forming jig 17 is provided with a winding cored bar (spindle shaft) 18 corresponding to the coil diameter at the center of the disc-shaped base, and this cored bar 18 This is a structure in which a protruding portion 17a that holds and holds the tip of the wire 11 is formed on the outer peripheral side of the base so as to face the peripheral surface. In addition, 17b is a notch part for relief formed in the side line of the base in order to avoid interference with the lead part on the coil winding side wound around the cored bar 18, and 19 is a guide for inserting the tip of the cored bar 18 This is a bearing.

With the above configuration, in the course of sending the coil wire 11 fed from the wire rod bobbin 12 to the coil forming part 16 at the time of coil forming, the insulation coating is peeled off at a constant pitch according to the size of the coil specified in advance. The feed guide 22 is fed from the side to the forming jig 17 of the coil forming portion 16, and the tip of the wire 11 is inserted into the gap between the cored bar 18 and the claw portion 17a as shown in FIG. Next, the rotary servo motor 20 shown in FIG. 4 is started to wind the wire rod 11 around the metal core 18 while rotating the forming jig 17 in the clockwise direction. Subsequently, the upper and lower servo motors 21 are also started to rotate. The forming jig 17 is pulled upward so as to give a coil pitch in synchronization with the above. As a result, the wire 11 is wound around the core bar 18 in a spiral manner as shown in FIG. When the number of turns of the coil reaches a specified number of turns (3 turns in the illustrated example), the rotary servo motor 20 is temporarily stopped, and then the upper and lower servo motors 21 pull the molding jig 17 further upward to raise the cored bar 18. Then, the rotary servo motor reverses and resets, and then the cutter 23 advances from the standby position to cut the wire 11 (see FIG. 6C). Thereby, the coil component having the shape shown in FIGS. 3B and 3C is formed. The cut and separated coil parts are taken out from the coil forming section and transferred to the next lead bending process. Here, the lead parts at both ends are bent into an L shape, and the coil parts having the final shape shown in FIG. Complete.
JP 2000-286139 A Japanese Patent Laid-Open No. 10-144556

By the way, when an electromagnetic coil is formed using the above-described conventional forming jig (see FIGS. 4 and 5), the following forming defects occur.
FIG. 7 is a shape view of an electromagnetic coil formed using the forming jig of FIGS. 4 and 5 as viewed from the lower surface side, and the end of the winding end side of the coil bulges outward from the peripheral surface of the core metal 18 and has a curvature. The lead portion 7c following this is curved in the longitudinal direction, and is not formed according to the shape shown in the figure by the chain line (the shape of FIG. 3C corresponding to the design specifications).
The cause of such defective molding is the rigidity of the coil wire 11 and the conventional coil molding method. That is, as shown in FIG. 8, when the wire 11 is wound around the core 18 of the forming jig 17 for a predetermined number of turns and the rotation of the forming jig 17 is stopped, the coil wire 11 fed through the supply guide 22 is tensioned. In addition, because of the bending rigidity of the coil wire 11, the coil end portion floats from the peripheral surface of the cored bar 18, so that the radius of curvature of the coil end portion increases and the shape as shown in FIG. 7 is exhibited. become. When a thick insulated wire having a wire diameter of, for example, about 4 to 5 mm is used as the coil wire material, the bending radius is remarkably increased at the end of the coil as described above due to its high bending rigidity. Dimensional accuracy decreases.
In addition, if the radius of curvature as described above is increased at the winding end of the molded coil component, the characteristics of the trip coil unit (see FIG. 2) vary, and leads are performed in the post-coil forming process. Bending work (see FIG. 3 (a)), assembly to the trip coil unit 6, and connection work between the lead part of the electromagnetic coil and the connection counterpart component of the circuit breaker are hindered.

  Therefore, the inventors have adopted a winding guide as disclosed in Patent Document 2, and the coil is pressed while pressing the wire rod against the peripheral surface of the metal core 18 at the portion where the wire 11 fed from the bobbin is wound around the metal core 18. Attempted to wind. According to this method, the molding defect as described in FIG. 7 is eliminated and the accuracy of the coil shape is improved. On the other hand, the insulation-coated electric wire supplied to the forming jig in a linearly extended state is closely attached to the peripheral surface of the core metal. Since a considerable force is applied to the pressing force, a large sliding frictional force acts on the insulating coating of the wire 11, and it is recognized that defects such as the insulating coating is peeled off due to the frictional heat generation and the insulating property is lowered. It was. In addition, when using a thick insulated wire having a wire diameter of about 4 to 5 mm, for example, the bending rigidity is high, so that the pressing force applied to press the insulated wire so as to be in close contact with the peripheral surface of the core metal Therefore, the insulation coating is easily damaged by frictional heat.

  The present invention has been made in view of the above points, and an object of the present invention is to improve an electromagnetic coil molding method that can stably form a coil with high dimensional and shape accuracy without damaging the insulation coating of the coil wire. And providing a molding apparatus.

In order to achieve the above object, according to the present invention, an insulation-coated electric wire is spirally wound as a coil wire, and a lead portion with the insulation coating peeled off from both ends of the coil winding start and winding ends is drawn. An electromagnetic coil forming method, in which the coil forming process is provided with a wound cored bar corresponding to the coil diameter, and the tip of the coil wire fed from the bobbin is locked to the forming jig, and then the forming jig is rotated. , In the case where the wire is wound around the peripheral surface of the core metal by feeding operation, the coil wire is wound around the end portion of the wire wound around the core metal in the final stage of the coil forming process of winding the coil wire around the core metal of the forming jig. A process of applying pressure from one side and pressing the wire against the rotating core is added (Claim 1), and the pressurizing region is angled from the end of the final turn of the coil. about It is set within the range of 30 ° (claim 2).

  The forming apparatus of the present invention for carrying out the forming method includes a coil forming jig in which a coil forming portion is provided with a winding core corresponding to a coil diameter, and a claw portion for locking and holding a winding start end portion of the coil wire. And a direct-acting pressure tool arranged on the side of the wire feeding side facing the core metal peripheral surface of the forming jig, and rotating and feeding the forming jig to operate the wire In the final stage of the coil forming process of winding the wire around the peripheral surface of the core metal, the pressurizing tool is advanced from the retracted position and the end portion of the wire is pressed against the peripheral surface of the rotating core metal to be handled (claim). 3).

  According to the above coil forming method, the coil wire (insulated coated electric wire) slides with the pressure tool since the pressure tool is retracted to the standby position in the process from the start to the end of the coil forming process. Without being wound around the core of the forming jig. Therefore, in this stroke range, the insulation coating of the coil wire fed from the bobbin is not likely to be damaged by the sliding frictional heat with the pressurizing tool. Then, when the coil forming process proceeds near the end (in the range of about 30 ° from the end of the coil final turn), the pressurizing tool advances from the standby position so that the end portion of the wire moves around the core metal peripheral surface. Press on. As a result, the coil is forcibly handled in accordance with the peripheral surface of the rotating metal core, and as a result, the winding end portion of the coil is designated without causing the molding defect described in FIGS. Can be formed with a radius of curvature of. In addition, the pressure tool is pressed against the coil wire only in the final stage of the coil forming process (about 30 ° in angle), and since the sliding range with the pressure tool is short, the insulation coating of the wire is caused by sliding frictional heat. Thus, an electromagnetic coil having high shape and dimensional accuracy can be formed while maintaining insulation without being damaged.

Hereinafter, embodiments of the present invention will be described based on the examples of FIGS. In the drawing of the embodiment, members corresponding to those in FIG. 4 and FIG.
That is, in the illustrated embodiment, a direct-acting pressure tool 24 is additionally provided at a side position on the side where the coil wire 11 is fed and fed against the core 18 implanted in the forming jig 17. Yes. The pressurizing tool 24 is connected to a drive cylinder (for example, an air cylinder) 25 and is driven to reciprocate between a standby position indicated by a chain line and a forward position indicated by a solid line based on a command, and is fed out through a supply guide 22 at the forward position. The coil wire 11 is pressed against the peripheral surface of the core metal 18, and the wire is forcedly handled along the peripheral surface of the core metal in accordance with the rotation of the core metal 18.
Here, the timing at which the pressurizing tool 24 is operated forward to press the wire 11 against the peripheral surface of the cored bar 18 is the final stage of the coil forming process, and the pressurizing range α is the final of the coil wound around the cored bar 18. The angle is set in the range of about 30 ° before the end of the turn. Then, at the beginning of coil forming, the pressurizing tool 24 is retracted to the standby position, and when the winding of the wire has advanced to the above position, the pressurizing tool 24 is advanced from the standby position by operating the drive cylinder 25, The wire 11 is pressed against the peripheral surface of the metal core 18 with the applied pressure so as to be handled.

As a result, the wire 11 is formed in the shape of the peripheral surface of the cored bar 18 at the winding end part of the coil, so that the end of the coiled wire 11 wound around the cored bar 18 as described in FIGS. A molding defect in which the portion floats from the peripheral surface of the cored bar and the radius of curvature increases is eliminated.
As a result, the molded electromagnetic coil is molded accurately according to the designated shape shown in FIGS. 3B and 3C without causing the molding defects described in FIGS. The Moreover, the range in which the pressing tool is pressed against the coil wire is the final range of the coil forming process. (The angle is about 30 degrees), and since the sliding range with the pressurizing tool is short, the insulation coating of the coil wire material is not peeled off by sliding frictional heat. An electromagnetic coil with high dimensional accuracy can be formed. This has also been confirmed from the result of a molding test performed by an actual machine performed by the inventors.

BRIEF DESCRIPTION OF THE DRAWINGS It is a structure and arrangement | positioning figure of the coil shaping | molding part by the Example of this invention, (a), (b) is a lower surface and a front view, respectively. Configuration diagram of circuit breaker to which electromagnetic coil of the present invention is applied It is a coil shape figure defined by the specification of the electromagnetic coil used for the trip coil unit with which the circuit breaker of FIG. 2 is equipped, (a) is a side view in a state where lead bending is performed, and (b) is before lead bending. The side view of the coil shaping | molding state of (c) is a top view of (b) FIGS. 3B and 3C are configuration diagrams schematically showing a molding apparatus for producing the coil component shown in FIGS. 3B and 3C, wherein FIG. 3A is a process diagram of the entire apparatus, and FIG. Detailed configuration diagram FIG. 5 is a detailed structural diagram of a forming jig employed in the forming apparatus of FIG. 4, wherein (a) and (b) are a side view and a bottom view, respectively. FIG. 6 is an explanatory diagram of a coil forming process by the forming jig of FIG. 5, and (a), (b), and (c) are diagrams showing states of winding start, winding in progress, and winding end, respectively. Shape of electromagnetic coil molded using the molding jig of FIG. The figure which shows the winding end state of the wire rod by the conventional coil forming method

Explanation of symbols

7 Electromagnetic coil 7a Coil body part 7b Lead part on the winding start side 7c Lead part on the winding end side 7d Wire 7e Insulation coating 11 Coil wire rod 17 Molding jig 18 Core metal (spindle shaft)
24 Pressing tool 25 Drive cylinder α Pressurizing range

Claims (3)

This is an electromagnetic coil molding method in which an insulation coated electric wire is spirally wound as a coil wire, and leads are drawn out from both ends of the coil winding start and end of winding. The coil forming jig is a coil A winding cored bar corresponding to the diameter is provided, and the tip of the coil wire fed from the bobbin is locked to the forming jig, and then the forming jig is rotated and reworked so that the wire is placed on the peripheral surface of the cored bar. In the end of the coil forming process in which the coil wire is wound around the core of the forming jig in the one that is wound around, the pressure is applied from the side to the terminal portion of the wire wound around the core and the wire is rotated. A method for forming an electromagnetic coil, comprising a step of pressing against a peripheral surface of a core metal. The molding method according to claim 1, wherein the pressurizing region for applying pressure to the wire rod from the side and pressing it against the core metal peripheral surface is set to a range of about 30 ° before the end of the coil final turn. A method for forming an electromagnetic coil, characterized by comprising: An electromagnetic coil forming apparatus having a shape in which an insulation coated electric wire is spirally wound as a coil wire, and leads are formed by pulling out lead portions from which both ends of the coil winding start and end of winding are drawn, and the coil forming portion of the apparatus Is a winding cored bar corresponding to the coil diameter, a coil forming jig provided with a claw portion for locking and holding the winding start end of the coil wire, and a wire feeding side facing the peripheral surface of the cored bar of the forming jig The pressure tool is retracted in the final stage of the coil forming process in which the wire is wound around the core by rotating and feeding the forming jig. The electromagnetic coil forming apparatus is characterized in that the terminal portion of the wire wound around the core is pressed against the peripheral surface of the rotating core.

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