JPH11329702A - Coil device for induction heating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the stiffness of a device and enhance heating efficiency by installing a heating coil produced by winding the specified number of times a hollow pipe inside of which the circulation path of cooling water is formed, coil supporting parts connected to both ends of the hollow pipe installed on the outside of the heating coil, and conductive plates connected to the coil supporting parts, and interposing a capacitor for resonance between the conductive plates. SOLUTION: A coil device 1 has a heating coil part 2 and a capacitor part 4 detachably connected to coil supporting parts 3 supporting the heating coil part 2. The heating coil part 2 is formed by spirally winding a circular copper pipe 5. The coil supporting parts 3 are formed with square copper pipes 6, 7 brazed to both ends of the copper pipe 5 and a pair of L-shape bent copper plates 8, 9. A gap and a pair of long holes 8a, 9a in the long direction are formed between the copper plates 8, 9, and the capacitor part 4 is position- adjustably connected to the long holes 8a, 9a. Even if the heating coil part 2 is mechanically protected and positioned far from an induction heating part, drop in heating efficiency can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a high-frequency induction heating,
The present invention relates to a coil device for induction heating used for induction hardening and the like.

[0002]

2. Description of the Related Art Conventionally, a coil device is indispensable for a high-frequency induction heating device, and a coil device disclosed in, for example, Japanese Utility Model Publication No. 62-5037 is known. This coil device comprises an induction heating coil member comprising two plate-shaped coil mounts, a hollow pipe fixed to the coil mount and having a cooling water circulation path formed therein, and abutting the coil mounts. And a resin insulating plate provided on the end face.

[0003]

However, in this coil device, the induction heating coil member includes a helical portion formed by helically winding a hollow pipe and both ends of the helical portion. It is formed by a parallel part extending in a direction perpendicular to the axis of the part, and the spiral part is provided at the tip of the parallel part, so the rigidity of the spiral part is inferior, for example, the outer diameter of the hollow pipe used Is limited.

As a result, for example, in order to increase the impedance of the coil device, when the number of turns of the helical portion is increased by using a small-diameter hollow pipe, the helical portion comes into contact with the work during use and the like. The shape portion is easily deformed, so that the reliability of the coil device is deteriorated, and it is difficult to easily set the number of turns of the spiral shape portion corresponding to various works.

Although it is good to directly connect the coil mount to a transformer installed in the induction heating device,
For example, when the spiral portion is moved and set on a work at a predetermined position, the heating efficiency of the coil device is degraded due to the inductance of the connection cable connecting the induction heating device and the coil device. There is a problem that a large capacity is required for itself.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a coil device for induction heating which can increase the rigidity of the coil device and improve the heating efficiency. To provide. Claim 2
Another object of the present invention is to provide a coil device for induction heating which can replace the coil device according to the form of a work and can improve versatility of use, in addition to the object of the invention described in claim 1.

[0007]

In order to achieve the above object, according to the present invention, there is provided a heating coil section in which a hollow pipe having a cooling water circulation path formed therein is wound a predetermined number of times. A coil support portion provided over substantially the entire area outside the heating coil portion in the axial direction of the coil portion and connected to both ends of the hollow pipe; and a conductive plate connected to the coil support portion. And a capacitor section in which a resonance capacitor is inserted.

[0008] With this configuration, the heating coil section in which the hollow pipe is wound a predetermined number of times has a coil supporting section connected to both ends thereof, which extends outside the heating coil section in the axial direction and along the axial direction. Since the heating coil portion is provided over substantially the entire area in the direction, the heating coil portion can be mechanically protected by the coil support portion, and the rigidity of the heating coil portion itself is increased. Also, since the resonance capacitor is inserted between the conductive plates of the capacitor unit connected to the coil support,
The inductance of the connection cable connected to the capacitor part can be canceled by the resonance capacitor, and even if the heating coil part is used at a predetermined distance from the induction heating device, the heating efficiency of the coil device is prevented from lowering. Is done.

Further, the invention according to claim 2 is characterized in that the heating coil portion and the coil support portion are integrally formed and detachably connected to the capacitor portion. With this configuration, the integrated heating coil unit and coil support unit can be separated from the capacitor unit. Therefore, depending on the form of the work, the capacity of the induction heating device, and the length of the connection cable, etc. The versatility in the use of the coil device is greatly improved, for example, it is possible to replace and use the section and the condenser section, and to easily cope with various works and induction heating devices.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view showing one embodiment of a coil device for induction heating according to the present invention.

In FIG. 1, a coil device 1 has a heating coil section 2, a coil supporting section 3 for supporting the heating coil section 2, and a capacitor section 4 detachably connected to the coil supporting section 3. doing. The heating coil unit 2 is formed by winding a circular copper pipe 5 in a spiral shape a predetermined number of times, for example, by inserting an insulating tube around the outer peripheral surface of the copper pipe 5 or by using an insulating resin. Is applied to form an insulating film (not shown). Further, the diameter and the number of turns of the heating coil unit 2 are set according to the form of a work (not shown) to be induction-heated.

The coil supporting portion 3 includes rectangular copper pipes 6 and 7 brazed to both ends of the copper pipe 5 of the heating coil section 2 and a pair of copper pipes 6 and 7 brazed and fixed. It is formed of copper plates 8 and 9. Copper pipes 6, 7
Are bent in an L-shape, one side of each of which is arranged in the axial direction of the heating coil unit 2 and is disposed close to the outer peripheral surface side of the heating coil unit 2, and the other side is a rectangular copper plate 8. , 9 and joints 10 to which a hose (not shown) for cooling water is connected are respectively fixed to the ends of the joints by brazing.

A predetermined gap is formed between the pair of copper plates 8 and 9, or a front edge plate (not shown) is interposed to be insulated. In addition, the copper plates 8 and 9 of the coil support 3 include
A pair of long holes 8a and 9a are formed in the longitudinal direction, and the capacitor portion 4 is connected and fixed to the long holes 8a and 9a by bolts 11 and nuts 12 so as to be position-adjustable.

The capacitor section 4 has a capacitor 15 formed in, for example, a rectangular parallelepiped shape, a plurality of electrode terminals 13 protruding from one end face thereof, and a pair of joints 14 for cooling water provided. . This capacitor 1
Insulating plates 16 are disposed on both sides in the thickness direction of the capacitor 5, and the opposed insulating plates 16 are connected by bolts 18 via the insulating plates 17, so that the capacitor 15 is connected to the pair of insulating plates 16. It is pinched by.

A flat mounting plate 20 which is larger than the insulating plate 16 and is connected to a jig or an output deformer by mounting bolts 19 is fixed to one of the insulating plates 16. Further, a pair of connecting members 21 made of a copper plate or the like are fixed to the coil supporting unit 3 side of the capacitor unit 4, and mounting holes (not shown) are formed in the connecting members 21. The mounting hole of the connecting member 21 and the long holes 8a and 9a of the copper plates 8 and 9 of the coil supporting portion 3 are made to coincide with each other. The part 3 is detachably connected. The connection between the connecting member 21 and the copper plates 8 and 9 can be performed by fixing the head of the bolt 11 to the connecting member 21 in advance.

Next, an example of a method of using the coil device 1 will be described. First, the mounting plate 20 of the capacitor unit 4 is mounted by a bolt 19 on a jig which can be moved to a set and non-set position with respect to, for example, a workpiece to be induction heated. In addition, one end of a flexible connection cable connected to the transistor inverter is connected to the electrode terminal 13 of the capacitor 15 of the capacitor section 4 and each joint 16 is connected to a cooling water supply device for cooling water. Connect hoses (none shown).

Then, the jig at the non-set position is moved with respect to the work, and the work is positioned in the heating coil section 2 of the coil device 1 to be set. At this time, since the coil supporting portion 3 is located close to the outer peripheral surface side of the heating coil portion 2 in the axial direction, the coil device 1 is simply moved by the jig in the direction of arrow A in FIG. It can be easily set at the set position.

When the heating coil section 2 of the coil device 1 is set at the set position, the transistor inverter is operated to supply a high-frequency current to the coil device 1 via the connection cable. Thereby, the capacitor 15 and the connecting member 2
1, a high-frequency current is supplied to the heating coil unit 2 via the copper plates 8 and 9 and the copper pipes 6 and 7, and an eddy current is induced in the work by the magnetic flux generated from the heating coil unit 2 so that the work is induction-heated.

Simultaneously with the supply of the high-frequency current from the transistor inverter, the cooling water is circulated and supplied from the cooling water supply device to the coil device 1 via the tube in the connection cable. This cooling water circulates and cools the condenser 15 through the joint 14, and the copper pipes 6 and 7 and the copper pipe 5 of the heating coil unit 2 through the joint 10.
Circulating through the inside to suppress a rise in the temperature of the heating coil unit 2.

After the induction heating for a predetermined time in this way, the operation of the transistor inverter and the cooling water supply device is stopped, and an appropriate process is performed, for example, moving the jig to the non-set position and removing the work. Thus, the induction heating operation is completed. For example, when changing the form of the workpiece to be induction-heated, the nuts 12 are loosened to remove the copper plates 8 and 9 of the coil support 3 from the connecting member 21. Then, the heating coil portion 2 (coil support portion 3) is replaced with another heating coil portion 2 (coil support portion 3) whose winding number and shape are set according to the work, and induction heating is performed.

As described above, in the coil device 1 of the above embodiment, the coil support portion 3 having the copper plates 8 and 9 is heated by the heating coil portion 2 in which the copper pipe 5 is spirally wound. Since the heating coil 2 is mechanically protected by the coil support 3 because the coil 2 is disposed close to the outer circumferential surface of the coil 2 in the axial direction, the coil support 3 is heated as in the related art. The rigidity of the heating coil unit 2 can be increased as compared with the case where the coil unit 2 is provided extending in the axial direction. As a result, even when the diameter of the copper pipe 5 forming the heating coil section 2 is small, the shape can be stably maintained and the small-diameter copper pipe 5 can be wound many times. , The number of turns of the heating coil unit 2, that is, the coil device 1
Can be easily set to a predetermined value.

Further, since the heating coil section 2 and the coil support section 3 are integrated and are detachably connected to the condenser section 4 by means of bolts 11 and nuts 12, the nuts 12 can be removed when the form of the work is different. By loosening, the heating coil unit 2 and the like can be easily replaced, and the heating coil unit 2 having the optimum shape and the number of turns according to the form of the work is used.
Can be used. Also, by removing the connection cable connected to the electrode terminal 13 and the joint 14 of the capacitor section 4, the capacitor section 4 can be replaced. Therefore, according to the length of the transistor inverter and the connection cable, the form of the work, and the like. , The capacitance of the capacitor 15 can be set to an optimum value.

Further, since the coil device 1 is connected to a transistor inverter as an induction heating device by a flexible connection cable, the coil device 1 can be easily moved to a predetermined position where a work is set. . For these reasons, the versatility of use can be greatly improved, for example, the coil device 1 can be used for various works.

Further, since the resonance capacitor 15 is integrated with the coil device 1, the inductance of the connection cable can be canceled by the capacitor 15, the transmission loss of the high-frequency current by the connection cable can be suppressed, and the transistor inverter can be prevented. Can be downsized,
Heating efficiency by the coil device 1 can be improved.

FIG. 2 is a perspective view showing another embodiment of the coil device according to the present invention. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. The feature of the coil device 1 of this embodiment is that the copper plates 8 and 9 of the coil support portion 3 are provided outside the heating coil portion 2 in the axial direction. That is, one end of each of the L-shaped copper pipes 6 and 7 is brazed and fixed to both ends of the copper pipe 5 of the heating coil unit 2, and the other ends are projected downward from the lower edges of the copper plates 8 and 9. The joint 10 is brazed to the end and fixed.

Further, the copper plates 8 and 9 are formed in a rectangular shape, and are arranged close to the outer peripheral surface side in the axial direction of the heating coil portion, and each of the prism-shaped connecting portions 23 are brazed and fixed to the right end thereof. One end of an H-shaped connecting member 24 having a joint 25 connected to an end of the capacitor section 4 is detachably connected to the connecting portion 23 by a bolt or the like (not shown). An insulating plate 27 having a connector 26 is provided at an end of the capacitor 4 on the electrode terminal side.
Has been fixed.

In this embodiment, the same operation and effect as those of the above embodiment can be obtained.
Since the heating coil 9 is disposed in the vicinity of the outer peripheral surface in the axial direction of the heating coil 2, the heating coil 2 can be reliably mechanically protected, and the effect of increasing the rigidity of the coil device 1 can be obtained. can get.

In the above embodiment, the case where the mounting plate 20 of the capacitor section 4 is mounted on the jig and the connection cable is connected to the electrode terminal 13 of the capacitor 15 has been described as an example. Without limitation, for example, the electrode terminal 13 of the capacitor 15 is directly connected to the secondary side of an integrated or separate output transformer of the transistor inverter, or the mounting plate 20 is attached to the housing of the transistor inverter. It can be configured to be directly fixed. In addition, the configuration, shape, connection structure, and the like of the heating coil unit 2, the coil support unit 3, and the capacitor unit 4 in the above embodiment are also examples, and may be appropriately set according to the form of the work to be induction-heated. it can.

[0029]

As described in detail above, according to the first aspect of the present invention, the heating coil portion in which the hollow pipe is wound a predetermined number of times extends along the outer side in the axial direction and over substantially the entire area in the axial direction. Since the heating coil unit is mechanically protected by the coil supporting unit because it is supported by the coil supporting unit provided over the entire surface, the rigidity of the heating coil unit itself is increased, and the shape of the heating coil unit is stabilized. Can be maintained.

Further, since the resonance capacitor is interposed between the electrodes of the capacitor portion electrically connected to the coil support portion, the inductance of the connection cable connected to the capacitor portion can be canceled by the resonance capacitor. Therefore, even when the coil device is used at a predetermined distance from the induction heating device, the transmission loss can be suppressed, and a decrease in the heating efficiency by the coil device can be prevented.

According to the second aspect of the present invention, since the integrated heating coil portion and coil support portion can be separated from the capacitor portion, the form of the work, the capacity of the induction heating device, and the length of the connection cable are provided. According to the above, the heating coil unit and the condenser unit can be exchanged and used, and it is possible to easily cope with various works and induction heating devices. Has the effect of

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a coil device for induction heating according to the present invention.

FIG. 2 is a perspective view showing another embodiment of the coil device for induction heating according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coil apparatus 2 Heating coil part 3 Coil support part 4 Capacitor part 5 Copper pipe 6, 7 Copper pipe 8, 9 Copper plate 10 Joint 13 Electrode terminal 14 Joint 15 Capacitor 20 Mounting plate 21 Connection member 23 Connection part 24 Connection member 26 Connector part

Claims (2)

[Claims] 1. A heating coil portion formed by winding a hollow pipe having a cooling water circulation passage formed therein a predetermined number of times, and provided substantially over the entire area outside the heating coil portion in the axial direction of the heating coil portion. A coil support portion connected to both ends of the hollow pipe, a capacitor portion having a conductive plate connected to the coil support portion and a resonance capacitor interposed between the conductive plates,
A coil device for induction heating, comprising: 2. The coil device for induction heating according to claim 1, wherein said heating coil portion and said coil support portion are integrally formed and detachably connected to said capacitor portion.