High-frequency induction heating head and high-frequency induction heating device using the same

Abstract

Disclosed is a high-frequency induction heating head and a high-frequency induction heating device using the same, which aims to suppress damage to a core that constitutes the high-frequency induction heating head. The high-frequency induction heating head of the present invention is provided with a core (4) having a magnetic gap (27) that becomes a heating portion, a coil (5) that supplies magnetic flux to the core (4), and a cooling unit that cools the coil (5), and a protection plate (30, 31) is provided that covers at least a portion of the outer surface of the core (4) other than the magnetic gap (27) portion in a heat-conducting manner, and the protection plate (30, 31) is composed of a metal material having a relative magnetic permeability lower than that of the core (4) and an electrical resistance value lower than that of the core (4).

Description

TECHNICAL FIELD

[0001] The present application relates to a high-frequency induction heating head and a high-frequency induction heating device using the same. BACKGROUND

[0002] The high-frequency induction heating head is used as a heating head that welds an electronic component to a pad portion of a circuit substrate, for example, as in Patent Document 1.

[0003] The high-frequency induction heating head is configured to have a core that has a magnetic gap that becomes a heating portion, a coil that supplies magnetic flux to the core, and a cooling unit that cools the coil.

[0004] That is, in a case where a terminal portion of an electronic component is welded to a pad portion of a circuit substrate, first, the terminal portion of the electronic component is fitted to the pad portion of the circuit substrate, and then, a welding wire is supplied to a welding portion of the pad portion and the terminal portion.

[0005] In addition, the welding portion is made to be in a state of being disposed in the magnetic gap of the core, and the welding portion and the welding wire are inductively heated by the magnetic flux generated in the magnetic gap.

[0006] In addition, since a large current flows in the coil, the coil is made to be tubular, and cooling water is made to flow inside the coil.

[0007] In addition, a scheme in which the core is also cooled by the cooling water has been proposed.

[0008] PRIOR ART DOCUMENTS

[0009] Patent Document 1: Japanese Patent Application Publication No. 2014-120649 SUMMARY

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] In the above-described prior art, the core is formed of a ferrite material or the like.

[0012] That is, since the permeability of the ferrite material is high and the electrical resistance is high, the eddy current loss in the high-frequency region is small, and the ferrite material is often used as a constituent of the core of the high-frequency induction heating head.

[0013] However, the core formed of a sintered ferrite material is as fragile as ceramic with respect to a drop or an impact due to a collision with other articles, and is easily damaged.

[0014] For example, in the above-described welding process, when the circuit substrate is moved toward the high-frequency induction heating head by an XY stage or the like, if other electronic components that have been fitted to the circuit substrate collide with the core, the core is damaged, and as a result, the core can need to be replaced, resulting in a reduction in productivity.

[0015] Therefore, the present application aims to suppress damage to the core and the like.

[0016] Solution for solving the problem

[0017] The high-frequency induction heating head according to the present application is characterized by comprising: a core having a magnetic gap that becomes a heating portion; a coil that supplies magnetic flux to the core; and a cooling unit that cools the coil, the high-frequency induction heating head having a protection plate that covers at least a portion of an outer surface of the core other than the magnetic gap portion in a heat-conducting manner, the protection plate being a metal material having a relative magnetic permeability lower than that of the core and an electrical resistance value lower than that of the core.

[0018] Here, the protection plate is a member that protects the core, and details will be described later, and it improves the heating efficiency of the magnetic gap.

[0019] Further, by covering in a heat-conducting manner, the cooling function is improved.

[0020] The present application does not limit the configuration or shape within the scope of the object.

[0021] In the present application, the core can be a plate-shaped body whose thickness dimension in the depth direction is smaller than the outer diameter dimension between the left and right outlines when viewed from the front, and the protection plate is disposed on one or both of the front surface and the back surface of the plate-shaped body.

[0022] Here, the front view of the core refers to a state of viewing from one face in a direction in which the gap forming the magnetic gap is seen, and in this state, the front side is set as the surface, and the opposite side is set as the back.

[0023] In addition, the outer diameter dimension of the core refers to the dimension between the left and right outlines of the core.

[0024] In the present application, in the core, the first sub-core of a C shape and the second sub-core of an inverted C shape can coincide with each other at one end side, and a magnetic gap formed by a gap can be formed between the other end side of the first sub-core and the other end side of the second sub-core.

[0025] Further, a first through-hole that penetrates the first sub-core and the second sub-core can be provided at the coinciding portion of the one end side of the first sub-core and the second sub-core, a penetration axis can penetrate the first through-hole, and the size of the magnetic gap formed by the gap at the other end side of the first sub-core and the second sub-core can be changed with the penetration axis as a switching axis.

[0026] In the present application, it can be provided that the protection plate is composed of a first sub-protection plate and a second sub-protection plate, the protection plate is provided on one or both of the front and back surfaces of the pair of first and second sub-cores, and the first and second sub-protection plates are provided corresponding to the first and second sub-cores, respectively.

[0027] It can also be that the outer shape of the sub-core is substantially the same as that of the sub-protection plate.

[0028] Here, the substantially same outer shape means that the shape and size are approximately the same.

[0029] In addition, it can also be that the core is formed of a ferrite material and the protection plate is formed of a copper material or an aluminum material.

[0030] It can also be that a heat-conductive grease is present between the core and the protection plate.

[0031] Here, the heat-conductive grease is preferably a silicone-based grease.

[0032] Also, it can be that the cooling unit is configured to make the coil tubular and to make cooling water flow in the tube, and to thermally couple a part of the tubular coil to the protection plate via a heat-conductive member.

[0033] In addition, it can also be that a through shaft is held to the heat-conductive member, and the surface of the protection plate on the side opposite to the core is brought into abutment with the heat-conductive member.

[0034] Note that the invention can also be provided with a blow unit that performs air cooling of the core and the protection plate.

[0035] The high-frequency induction heating device of the present application is characterized by comprising: the high-frequency induction heating head; and a holding unit that holds a heated body arranged in a magnetic gap portion of the high-frequency induction heating head.

[0036] As examples of the heated body, a welding portion, a component in which a specific portion is desired to be heated locally, and the like can be listed.

[0037] In this case, a temperature sensor can also be combined so as to be able to perform temperature control of the heated portion.

[0038] Effects of the Invention

[0039] As described above, the high-frequency induction heating head according to the present application is provided with a core having a magnetic gap that becomes a heating portion, a coil that supplies magnetic flux to the core, and a cooling unit that cools the coil, and a protection plate that covers at least a portion of an outer surface of the core other than the magnetic gap portion in a heat-conducting manner is provided, and the protection plate is composed of a metal material having a relative magnetic permeability lower than that of the core and an electric resistance value lower than that of the core.

[0040] Therefore, other articles can be protected from directly colliding with the core by the protection plate, and as a result, damage to the core can be suppressed.

[0041] In addition, since the protection plate is composed of a metal material having a relative magnetic permeability lower than that of the core and an electric resistance value lower than that of the core, the amount of leakage of magnetic flux to the outside of the magnetic gap portion can be reduced, and as a result, the heating efficiency at the magnetic gap portion can be improved, and unintended heating of other structures in the vicinity can be prevented.

[0042] That is, the magnetic flux is concentrated in the magnetic gap portion in the core, but a portion thereof leaks to the outside of the core.

[0043] In the high-frequency induction heating head, since a large current flows, even if magnetic flux leaks, the structures in the vicinity can be sufficiently heated to a high temperature.

[0044] In the present application, the magnetic flux that leaks from the core passes through the protection plate having a relative magnetic permeability lower than that of the core, and in addition, since the protection plate is composed of a metal material having an electric resistance value lower than that of the core, due to the passage of the magnetic flux, eddy currents flow, and by the eddy currents, magnetic flux in the opposite direction to the magnetic flux that passed through the protection plate is generated, and as a result, the amount of magnetic flux that leaks from the core via the protection plate is reduced, and thus unintended heating of other structures in the vicinity can be prevented. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 A perspective view of a high-frequency induction heating device using the high-frequency induction heating head according to an embodiment of the present application.

[0046] Figure 2 A front view of the high-frequency induction heating device.

[0047] Figure 3 A side view of the high-frequency induction heating device.

[0048] Figure 4 A side view of the high-frequency induction heating device.

[0049] Figure 5 A perspective view of the high-frequency induction heating device with a portion removed.

[0050] Figure 6An exploded perspective view of the high-frequency induction heating device.

[0051] Figure 7 An exploded perspective view of the high-frequency induction heating device.

[0052] Figure 8 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0053] Figure 9 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0054] Figure 10 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0055] Figure 11 A front view of a high-frequency induction heating device using a high-frequency induction heating head according to another embodiment of the present application.

[0056] Figure 12 A side view of the high-frequency induction heating device.

[0057] Figure 13 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0058] Figure 14 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0059] Figure 15 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0060] Figure 16 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0061] Figure 17 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0062] Figure 18 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0063] Figure 19 An enlarged perspective view of the high-frequency induction heating head portion of the high-frequency induction heating device.

[0064] Figure 20 A control block diagram of the high-frequency induction heating device.

[0065] Figure 21 A flowchart for explaining the operation of the high-frequency induction heating device.

[0066] Explanation of reference numerals in the attached figures

[0067] 1: High-frequency induction heating head; 2: Main body shell; 2a: Upper surface; 2b: Lower surface; 2c: Outer peripheral surface; 2A: IH output connector; 3: Cooling water connector; 4: Core; 5: Coil; 6: Capacitor; 7: Electric-water circuit connector; 8: Electric-water circuit connector; 9: Water circuit joint; 10: Base; 11: Water circuit joint; 12: Water circuit joint; 13: Screw; 14: Screw; 15: Rubber sealing gasket; 16: Screw; 17: Coil base; 18: Coil base; 19: Water circuit joint; 20: Water circuit joint; 21: Insulating plate; 22: Screw; 23: Terminal; 24: Terminal; 25: Sub-core; 26: Sub-core; 27: Magnetic 28: Through hole; 29: Screw; 30: Protective plate; 31: Protective plate; 32: Sub-protective plate; 33: Sub-protective plate; 34: Through hole; 35: Sub-protective plate; 36: Sub-protective plate; 37: Through hole; 38: Heat-conducting component; 39: Screw hole; 40: Bending part; 41: Screw hole; 42: Bending part; 43: Through hole; 44: Mounting part; 45: Through hole; 46: Screw; 47: Screw; 48: Screw hole; 49: Welding wire supply device; 50: Radiation thermometer; 51: Radiation thermometer; 52: Circuit board; 53: Solder pad; 54: Terminal; 55: Control unit; 56: Timer; 57: Memory; 58: Power supply unit; 59: Holding unit. Detailed Implementation

[0068] Hereinafter, an embodiment of the present invention will be described using the accompanying drawings.

[0069] (Implementation Method 1)

[0070] Figures 1-4 In this embodiment, the high-frequency induction heating head 1 has a box-shaped main body housing 2.

[0071] The upper surface 2a, lower surface 2b, and four outer peripheral surfaces 2c of the main body shell 2 are all made of resin. An IH output connector 2A and two cooling water connectors 3 are provided on the upper surface 2a of the main body shell 2.

[0072] In addition, a core 4 and a coil 5 that supplies magnetic flux to the core 4 are arranged below the main housing 2.

[0073] like Figures 5-7 As shown, a capacitor 6 is disposed inside the main body shell 2, and electrical water circuit connectors 7 and 8 are respectively disposed on both sides of the capacitor 6 from the capacitor 6 side outward.

[0074] These electro-hydraulic connectors 7 and 8 are both made of copper and are capable of conducting electricity with the objects they come into contact with.

[0075] First, the electric water path connecting body 8 is shaped like a building as a whole, and a water path (not shown) extending in the vertical direction is formed inside it. At the upper end of the water path, a cooling water connection connector 3 is joined to the upper surface of the electric water path connecting body 8.

[0076] In addition, as shown in Figure 7 , the lower end of the water path inside the electric water path connecting body 8 becomes a water path joining portion 9 at the lower portion of the electric water path connecting body 8 on the side of the capacitor 6.

[0077] Next, the electric water path connecting body 7 is shaped like a plate as a whole, and a water path (not shown) extending downward from the lateral side to the side of the electric water path connecting body 8 is formed inside the base portion 10 at the lower portion.

[0078] Furthermore, as shown in Figure 6 , the end portion of the water path of the electric water path connecting body 7 to the side of the electric water path connecting body 8 becomes a water path joining portion 11.

[0079] In addition, as shown in Figure 7 , the end portion of the water path of the electric water path connecting body 7 to the lower end side becomes a water path joining portion 12.

[0080] In the above structure, if the metal-made screws 13, 14 shown in Figure 6 , Figure 7 are used to screw-fix the left and right electric water path connecting bodies 7, 8 to the fixing portion of the capacitor 6, as shown in Figure 5 , the electric water path connecting bodies 7, 8 become integrated on both sides of the capacitor 6, respectively.

[0081] In addition, by this integration work, the left and right electric water path connecting bodies 7, 8 each form a continuous water path to the cooling water connection connector 3, the water path inside the electric water path connecting body 8, the water path joining portion 9 thereof, the water path joining portion 11 of the electric water path connecting body 7, the water path of the electric water path connecting body 7, and the water path joining portion 12.

[0082] The integrated article of the capacitor 6, the electric water path connecting bodies 7, 8 becomes a state of being held on the lower surface 2b of the main body case 2 as shown in Figure 5 , and the cooling water connection connector 3 becomes a state of being led out to the through-hole A on the upper surface 2a of the main body case 2.

[0083] In addition, the lower surfaces of the base portions 10 of the two electric water path connecting bodies 7 are positioned at the through-hole B portion of the lower surface 2b of the main body case 2, whereby the water path joining portions 12 of the lower surfaces of the base portions 10 become a state of facing the outside of the main body case 2 via the through-hole B.

[0084] Furthermore, the core 4 and the coil 5 are connected by Figure 6 ,Figure 7 Screw 16 Figure 5 It is shown to be attached to the lower surface of the two base portions 10.

[0085] To explain in detail, firstly, the coil 5 is formed into a U-shape by a copper tube with water channels inside, and one end of the coil is connected to the front and rear coil bases 17 and 18 made of copper material, respectively.

[0086] In the front and rear coil bases 17 and 18, horizontal flanges 17a and 18a are formed on their respective upper sides. Through holes for screws 16 are formed in the flanges 17a and 18a. The screws 16 pass through the through holes of the flanges 17a and 18a from below and screw the screws 16 into the screw holes on the lower surface of the base portion 10 of the electro-hydraulic circuit connector 7. Thus, the front and rear coil bases 17 and 18 are combined with the base portion 10 of the electro-hydraulic circuit connector 7.

[0087] In addition, water channels (not shown) are formed in the coil bases 17 and 18 respectively in the vertical direction. The lower end of the water channel of the coil base 17 is connected to a water channel joint (not shown) on one end of the coil 5, and the lower end of the water channel of the coil base 18 is connected to a water channel joint (not shown) on the other end of the coil 5.

[0088] Additionally, at the upper end of the water channel of the coil base 17, the flange 17a, such as Figure 6 The water channel junction 19 is formed in such a way that the flange 18a at the upper end of the water channel of the coil base 18 is as follows: Figure 6 That's how the waterway junction 20 is formed.

[0089] Therefore, if through Figure 6 , Figure 7 Metal screws 16 fix coil bases 17 and 18 to the lower surfaces of the two base portions 10. The water passage joints 19 and 20 of the coil bases 17 and 18 are connected to the water passage joints 12 on the lower surfaces of the two base portions 10 via rubber sealing gaskets 15.

[0090] It should be noted that, for example, a waterway junction 9 and 11 is also sandwiched between them. Figure 7 The rubber sealing gasket 15 shown is used to prevent water leakage.

[0091] By adopting the above configuration, for example, when cooling water at 25°C flows from the one cooling water connection connector 3, the cooling water flows to the water passage in the one electric water passage connector 8, the water passage junction 9, the water passage junction 11 of the one electric water passage connector 7, the water passage in the one electric water passage connector 7, the water passage junction 12, the water passage junction 19 of the coil base 17, the water passage of the coil base 17, the water passage junction of one end side of the coil 5, the water passage of the coil 5, the water passage junction of the other end side of the coil 5, the water passage of the coil base 18, the water passage junction 20 of the coil base 18, the water passage junction 12 of the other electric water passage connector 7, the water passage of the other electric water passage connector 7, the water passage in the other electric water passage connector 8, the other cooling water connection connector 3, and then is cooled in the cooling portion of the main body case 2, and is circulated again to the above one cooling water connection connector 3.

[0092] Note that the coil bases 17, 18 are overlapped via the resin-made insulating plate 21, and the screw 22 that joins the two is resin-made and is insulating, so that short-circuiting electrical conduction between the coil bases 17, 18 does not occur.

[0093] In addition, Figure 5 One terminal of the IH output connection connector 2A and the terminal portion 23 of the one electric water passage connector 8 are connected by wiring (not shown in order to avoid complication of the drawing), and the other terminal of the IH output connection connector 2A and the terminal portion 24 of the other electric water passage connector 8 are connected by wiring (not shown in order to avoid complication of the drawing).

[0094] In addition, the capacitor 6 and the electric water passage connectors 7, 8 are also integrated by the above metal-made screws 13, 14, and are in an electrically connected state.

[0095] Also, the capacitor 6, the electric water passage connectors 7, 8, the coil bases 17, 18, and the coil 5 are in an electrically connected state.

[0096] That is, when power supply from the IH output connection connector 2A is performed, resonance is generated by the capacitor 6 and the coil 5, and this resonance current is supplied to the coil 5, and becomes a state in which magnetic flux is generated.

[0097] Next, the core 4 that performs heating based on this magnetic flux is described.

[0098] As Figures 8-10 shown, the core 4 is configured so that one end side (upper end side) of each of a first sub-core 25 in a C shape and a second sub-core 26 in an inverted C shape are overlapped, and a magnetic gap 27 formed by a gap is formed between the other end side (lower end side) of the sub-cores 25, 26.

[0099] That is, the core 4 is configured so that the respective one end sides (upper end sides) of the C-shaped sub-core 25 and the reverse C-shaped sub-core 26 are overlapped, thereby being annular in a front view, and a gap in which the magnetic gap 27 is formed is formed in a part of the annular shape.

[0100] Further, the coil 5 is made to linearly pass through the inner space of the annular core 4, thereby being configured so that the magnetic flux generated in the coil 5 flows to the core 4 and the magnetic gap 27.

[0101] In addition, the following configuration is made. A through-hole 28 that passes through the sub-cores 25 and 26 is provided at the overlapping portion of the one end sides of the sub-cores 25 and 26, a screw 29 is made to pass through the through-hole 28 as a through shaft, and the size of the magnetic gap 27 can be changed with the screw 29 as a switching shaft.

[0102] In addition, the core 4 is made to be a plate shape in which the plate thickness dimension in the depth direction is smaller than the outer diameter dimension in a front view, and a protection plate 30 and a protection plate 31 are respectively arranged on the front surface and the back surface of the plate-shaped core 4.

[0103] In the protection plate 30, the one end sides (upper sides) of a first sub-protection plate 32 that is C-shaped and a second sub-protection plate 33 that is reverse C-shaped are overlapped, and a through-hole 34 that passes through the sub-protection plates 32 and 33 is provided at the overlapping portion of the sub-protection plates 32 and 33, and the screw 29 passes through the through-hole 34 as the through shaft.

[0104] In addition, in the protection plate 31, the one end sides (upper sides) of a first sub-protection plate 35 that is C-shaped and a second sub-protection plate 36 that is reverse C-shaped are overlapped, and a through-hole 37 that passes through the sub-protection plates 35 and 36 is provided at the overlapping portion of the sub-protection plates 35 and 36, and the screw 29 passes through the through-hole 37 as the through shaft.

[0105] That is, the screw 29 passes through the through-hole 34 of the sub-protection plates 32 and 33 as the through shaft, then passes through the through-hole 28 of the sub-cores 25 and 26, and then passes through the through-hole 37 of the sub-protection plates 35 and 36, and is screwed into a screw hole 39 of a U-shaped heat conduction member 38.

[0106] Further, by this structure, the front surface and the back surface of the core 4 are made to be in a state in which heat conduction is possible, and are made to be in a state in which they are covered by the protection plates 30 and 31.

[0107] In addition, a bent portion 40 that is bent rearward so as to cover the upper surfaces of the sub-cores 25 and 26 is formed in the upper portions of the sub-protection plates 32 and 33, and a screw hole 41 is formed at this portion.

[0108] Furthermore, on the upper part of the sub-protective plates 35 and 36, a forward bending portion 42 is formed in such a way as to cover the rearward bending portion of the upper part of the sub-protective plates 32 and 33, and a through hole 43 is formed therein.

[0109] In addition, an outward mounting portion 44 is provided on the upper part of the sub-protection plates 35 and 36, and a through hole 45 is provided therein.

[0110] Through hole 43 becomes an elongated hole facing the front-back direction, and through hole 45 becomes an elongated hole facing the outer periphery.

[0111] In this structure, the protective plate 31, the core 4, and the protective plate 30 are overlapped and held and fixed to the heat-conducting component 38. However, as an example, the method is to first overlap the protective plate 31, the core 4, and the protective plate 30, and then align the axis by passing through the through hole 34, the through hole 28, and the through hole 37 with a rod-shaped clamp (not shown).

[0112] Next, screw 46 is screwed from above the protective plate 31 through the through hole 43 into the screw hole 41 of the protective plate 30, thereby setting the core 4 to be sandwiched from the front and back through the protective plates 30 and 31.

[0113] Furthermore, the rod-shaped clamp is pulled out from the temporarily unitized core 4, protective plates 30, 31, and then... Figure 9 The retaining part 38a of the heat-conducting component 38 allows the screw 29 to pass through the through holes 34, 28, and 37 of the protective plate 31, core 4, and protective plate 30, and the screw 29 is screwed into the screw hole 39 of the heat-conducting component 38.

[0114] In addition, screw 47 passes through the through hole 45 of the protective plate 31 and is screwed into the screw hole 48 of the heat-conducting component 38.

[0115] In this state, the size of the magnetic gap 27 is adjusted, and the screws 29 and 47 are finally tightened with force, thereby completing the holding and fixing of the protective plate 31, the core 4, and the protective plate 30 to the heat-conducting component 38.

[0116] If the above structure is adopted, the side of the protective plate 31 opposite to the core 4 will abut against the heat-conducting component 38, making it easy to conduct heat between the heat-conducting component 38 and the protective plate 31.

[0117] In other words, when the coil base 18 is cooled by the cooling water used to cool the coil 5, its low temperature is also used to cool the core 4 made of ferrite material through the copper heat-conducting component 38 and the copper protective plate 31. In this embodiment, even if it is operated continuously for 24 hours, the temperature of the core 4 can be suppressed to about 100°C.

[0118] The high-frequency induction heating head of the embodiment is a heating head that welds the terminal portion of the electronic component to the land of the circuit board in the magnetic gap 27 portion, and such a heating head that can continuously perform the welding work for 24 hours can drastically improve productivity.

[0119] Note that, in such a high-frequency induction heating head, as is well known, the land of the circuit board, the terminal portion of the electronic component, and the solder become heated bodies, and in high-frequency induction heating using the high-frequency induction heating head, a holding unit that holds the circuit board and the solder needs to be provided.

[0120] In addition, in the embodiment, the protection plates 30, 31 are made of a metal material that has a relative magnetic permeability lower than that of the core 4 and an electrical resistance value lower than that of the core 4.

[0121] Specifically, the core 4 is formed of a ferrite material, and the protection plates 30, 31 are formed of a copper material or an aluminum material.

[0122] The relative magnetic permeability of the ferrite material that constitutes the core 4 is 50 to 5000, and in the case where the protection plates 30, 31 are made of a copper material or an aluminum material, the relative magnetic permeability is approximately 1, and thus the magnetic flux flowing in the core 4 flows only within the core 4 and rarely leaks to the protection plates 30, 31.

[0123] However, in the embodiment, since a large current of about 100 A flows in the coil 5, even if the leakage magnetic flux is sufficiently small compared to the magnetic flux flowing through the magnetic gap 27, the structure near the core 4 is sometimes heated sufficiently and thus becomes high-temperature.

[0124] In contrast, in the embodiment, the magnetic flux leaking from the core 4 passes through the protection plates 30, 31 that have a relative magnetic permeability lower than that of the core 4, and in addition, the protection plates 30, 31 are made of a metal material that has an electrical resistance value lower than that of the core 4, and thus, by the passage of the magnetic flux, an eddy current flows, and by the eddy current, a magnetic flux in the opposite direction to the magnetic flux passing through the protection plates 30, 31 is generated, as a result of which the magnetic flux leaking from the core 4 through the protection plates 30, 31 is reduced, and thus, other structures near the core 4 are not unintentionally heated.

[0125] According to experiments, unintentional heating at a position 4 mm away from the magnetic gap 27 was reduced by 20%, and unintentional heating at a position 8 mm away was reduced by 40%.

[0126] Thus, an article that is not originally heated is not unintentionally heated by the magnetic flux from the core 4, and degradation does not occur.

[0127] Further, in the vicinity of the magnetic gap 27, an article that is not originally intended to be heated is not heated by the magnetic flux unintentionally, so that the degree of freedom of the heating operation is increased, and the productivity is also increased.

[0128] Further, the decrease in the magnetic flux leakage is also the increase in the magnetic flux of the magnetic gap 27, so that the heating efficiency can be increased.

[0129] Note that, in the case where the protective plates 30, 31 are formed of copper material, the electric resistance value is 1.68 x 10 -8 Ωm, and, in the case where the protective plates 30, 31 are formed of aluminum material, the electric resistance value is 2.83 x 10 -8 Ωm, and, in the case where the protective plates 30, 31 are formed of aluminum material, the electric resistance value is 2.83 x 10

[0130] Further, the outer shape of the core 4 and the outer shape of the protective plates 30, 31 are substantially the same, and the front surface and the back surface of the core 4 are covered with the protective plates 30, 31, so that other articles can be protected from colliding directly with the core 4 by the protective plates 30, 31, and as a result, the damage of the core 4 can be suppressed.

[0131] That is, since the core 4 is formed of ferrite, although the core 4 is easily damaged by the collision of other articles or the falling of the core 4 itself, if the outer shape of the core 4 and the outer shape of the protective plates 30, 31 are made substantially the same, and the front surface and the back surface of the core 4 are covered with the protective plates 30, 31, other articles can be protected from colliding directly with the core 4 by the protective plates 30, 31, and as a result, the damage of the core 4 can be suppressed.

[0132] Further, the thermal conductivity of the protective plate 31 is 403 W / m-K when formed of copper material, and the thermal conductivity is 236 W / m-K when formed of aluminum material, and the thermal conductivity is good, so that, when the coil 5 is cooled by cooling water, the core 4 can be sufficiently cooled via the protective plate 31, but if a thermally conductive lubricant such as silicone-based lubricant is interposed between the core 4 and the protective plate 31, the cooling effect can be further increased.

[0133] Note that, in the above embodiment, an example in which the core 5 is water-cooled is shown, but the configuration in which the core 5 is air-cooled can also be adopted.

[0134] For example, air for air-cooling can be sent to the thermally conductive member 38 and the protective plates 30, 31.

[0135] Further, for this purpose, fins can be provided on the thermally conductive member 38 and the protective plates 30, 31.

[0136] (Embodiment 2)

[0137] Figures 11-21 A diagram for showing other embodiments of the present application.

[0138] In this embodiment, the above-mentioned Figures 1-10 content explained in the

[0139] In this embodiment, for the sake of avoiding complication of explanation, the above-mentioned Figures 1-10 content explained in the Figures 1-10 is explained simply, but for the sake of accurately understanding it (Embodiment 2), the above-mentioned explanation of (Embodiment 1) is to be understood in its entirety.

[0140] Figures 11-21 In addition, in Figures 1-10 , for the sake of avoiding complication of the drawings, the symbols of all the components explained in the Figures 11-21 Figures 1-10 are basically the same.

[0141] In the embodiment of Figures 11-21 , it is characteristic to provide the solder wire supply device 49 as an example of the supply device of the solder, and to provide the radiation thermometers 50, 51 as examples of the temperature measuring unit.

[0142] The circuit board 52 is conveyed, for example, by an XYΘ table (not shown) as an example of the conveying unit, in such a manner that Figures 15-19 the circuit board 52 is conveyed in the direction of the arrow A.

[0143] In the land 53 portion of the circuit board 52, the terminal 54 of the electronic component mounted on the back surface of the circuit board 52 protrudes from the back surface side to the surface side.

[0144] This terminal 54 is moved to between the magnetic gaps 27, and in this state, the terminal 54 is soldered to the land 53 portion.

[0145] In this state, the radiation thermometer 50 measures the temperature of the upper end portion of the terminal 54, and the radiation thermometer 51 measures the temperature of the land 53 portion and the lower portion of the terminal 54.

[0146] In addition, these radiation thermometers 50, 51 are connected to the control section 55 as shown in Figure 20

[0147] In the control section 55, a timer 56, a memory 57 (a program, etc. built in), a power supply section 58 are connected, and the coil 5 and the capacitor 6 are connected to the power supply section 58. Figure 21

[0148] Note that, as shown in Figure 15 , the solder wire supply device 49 is held by the holding member 59 to the heat conductive member 38, and the solder wire is appropriately supplied from the solder wire supply device 49 to the magnetic gap 27 portion.​​​

[0149] In addition, the radiation thermometers 50, 51 are held to the main body case 2 by other holding units, but the holding units are not shown in order to avoid complication of the drawing.

[0150] In the above structure, the circuit board 52 is conveyed by an XYΘ table (not shown), as shown in Figure 18 When the terminal 54 is disposed in the magnetic gap 27 portion, as a preheating, the supply of the power to the coil 5 is started (S1 of Figure 21 , and the temperature measurement by the radiation thermometers 50, 51 is also started (S2 of Figure 21 ).

[0151] In this preheating, the heating is performed at, for example, 120 A, 70 W.

[0152] As shown in Figures 17-19 , the radiation thermometer 50 measures the temperature of the upper end portion of the terminal 54.

[0153] In addition, as shown in Figures 17-19 , the radiation thermometer 51 measures the temperature of the pad 53 portion, the lower portion of the terminal 54.

[0154] First, it is determined whether the measured temperature measured by the radiation thermometer 50 (the temperature of the upper end portion of the terminal 54) exceeds the solder melting temperature (for example, 300°C) (S3 of Figure 21 ).

[0155] If the temperature of the upper end portion of the terminal 54 does not exceed 300°C, then it is determined whether the measured temperature measured by the radiation thermometer 51 (the temperature of the pad 53 portion, the lower portion of the terminal 54) exceeds the overheat threshold temperature (for example, 350°C) (S4 of Figure 21 ).

[0156] If the measured temperature measured by the radiation thermometer 51 (the temperature of the pad 53 portion, the lower portion of the terminal 54) does not exceed the overheat threshold temperature (for example, 350°C), the preheating is continued by returning to (S3 of Figure 21 ).

[0157] If the measured temperature measured by the radiation thermometer 51 (the temperature of the pad 53 portion, the lower portion of the terminal 54) exceeds the overheat threshold temperature (for example, 350°C), the supply of the power to the coil 5 is stopped (S5 of Figure 21 ).

[0158] In addition, in (S3 of Figure 21 ), when the temperature of the upper end portion of the terminal 54 exceeds 300°C, then it is determined whether the measured temperature measured by the radiation thermometer 50 (the temperature of the upper end portion of the terminal 54) exceeds the overheat threshold temperature (for example, 350°C) (S6 ofFigure 21 (S6).

[0159] exist( Figure 21 In S6), when the temperature of the upper portion of terminal 54 exceeds the overheat threshold temperature (e.g., 350°C), the power supply to coil 5 is stopped. Figure 21 (S7).

[0160] exist( Figure 21 In step S6), if the temperature of the upper portion of terminal 54 does not exceed the overheating threshold temperature (e.g., 350°C), then it is determined whether the measured temperature (temperature of the pad 53 portion and the lower portion of terminal 54) measured by the radiation thermometer 51 exceeds the solder melting temperature (e.g., 300°C). Figure 21 (S8).

[0161] exist( Figure 21 In S8), if the measured temperature (temperature of the pad 53 portion, the lower portion of the terminal 54 portion) measured by the radiation thermometer 51 does not exceed the solder melting temperature (e.g., 300°C), then return ( Figure 21 (S3), continue preheating.

[0162] In addition, in ( Figure 21 In S8), if the measured temperature (temperature of the pad 53 portion, the lower portion of the terminal 54) measured by the radiation thermometer 51 exceeds the solder melting temperature (e.g., 300°C), then it is determined whether the measured temperature (temperature of the pad 53 portion, the lower portion of the terminal 54, the solder temperature of that portion when solder is supplied) measured by the radiation thermometer 51 exceeds the overheating threshold temperature (e.g., 350°C). Figure 21 (S9).

[0163] exist( Figure 21 In S9), when the measured temperature (temperature of the pad 53 portion, the lower portion of the terminal 54) measured by the radiation thermometer 51 exceeds the overheating threshold temperature (e.g., 350°C), the power supply to the coil 5 is stopped. Figure 21 (S10).

[0164] In addition, in ( Figure 21 In S9), if the measured temperature (temperature of the pad 53 portion and the lower portion of the terminal 54) measured by the radiation thermometer 51 does not exceed the overheating threshold temperature (e.g., 350°C), then the welding wire supply via the welding wire supply device 49 begins. Additionally, as the main heating element, the output to the coil 5 is changed to 90A and 50W. Figure 21 (S11).

[0165] Next, it is determined whether the measured temperature (temperature of the upper part of terminal 54) measured by radiation thermometer 50 exceeds the overheating threshold temperature (e.g., 350°C). Figure 21 (S12).

[0166] exist( Figure 21 In step S12), if the measured temperature (temperature of the upper part of terminal 54) measured by radiation thermometer 50 exceeds the overheating threshold temperature (e.g., 350°C), then the power supply to coil 5 is stopped. Figure 21 (S13).

[0167] exist( Figure 21 In step S12), if the measured temperature (temperature of the upper part of terminal 54) measured by radiation thermometer 50 does not exceed the overheating threshold temperature (e.g., 350°C), main heating continues until the timer time of timer 56 (e.g., 2 seconds) is exceeded. Figure 21 (S14).

[0168] In addition, in ( Figure 21 In S14), if the timer duration is exceeded (e.g., 2 seconds), the power supply to coil 5 is stopped. Figure 21 Figure 21 (S15).

[0169] As described above, in this embodiment, the temperature of the upper portion of the terminal 54 is measured using a radiation thermometer 50, and the temperature of the pad 53 portion and the lower portion of the terminal 54 is measured using a radiation thermometer 51. Therefore, appropriate soldering can be performed by appropriate heating.

[0170] Furthermore, the circuit board 52 will not be damaged even under excessive heating conditions.

[0171] Industrial availability

[0172] The high-frequency induction heating head and the high-frequency induction heating device using the present invention can heat specific parts in a non-contact manner, and therefore can be used in welding devices, etc.

[0173] It should be noted that as long as the heated body can be held within the magnetic gap, it can be applied to many fields besides welding.

Claims

1. A high-frequency induction heating head characterized by comprising: Possessing: a core having a magnetic gap that becomes a heating portion; a coil that supplies a magnetic flux to the core; and a cooling unit that cools the coil, the high-frequency induction heating head has a protection plate that covers at least a portion of the outer surface of the core other than the magnetic gap portion in a heat-conducting manner, the protection plate is a metal material having a relative magnetic permeability lower than that of the core and an electrical resistance lower than that of the core.

2. The high-frequency induction heating head according to claim 1, wherein the core is a plate-shaped body having a thickness dimension in a depth direction smaller than a left-right outer diameter dimension when viewed from the front, and the protection plate is disposed on one or both of the front surface and the back surface of the plate-shaped body.

3. The high-frequency induction heating head according to claim 2, wherein the core is configured to be annular when viewed from the front, and a gap that forms the magnetic gap is formed in a portion of the annular shape.

4. The high-frequency induction heating head according to claim 3, wherein in the core, a first sub-core that is C-shaped and a second sub-core that is reverse-C-shaped are aligned on one end side of each, and a magnetic gap formed by a gap is formed between the other end side of the first sub-core and the other end side of the second sub-core.

5. The high-frequency induction heating head according to claim 4, wherein the high-frequency induction heating head is configured to have a first through-hole that penetrates the first sub-core and the second sub-core provided in the aligned portion of one end side of the first sub-core and the second sub-core, a through shaft that penetrates the first through-hole, and the size of the magnetic gap formed by the gap on the other end side of the first sub-core and the second sub-core can be changed with the through shaft as a switching shaft.

6. The high-frequency induction heating head according to claim 5, wherein the protection plate disposed on one or both of the front surface and the back surface of the pair of first sub-cores and second sub-cores is composed of a first sub-protection plate and a second sub-protection plate that are disposed to correspond to the first sub-core and the second sub-core, respectively.

7. The high-frequency induction heating head according to claim 6, wherein the outer shape of the sub-core and the outer shape of the sub-protection plate are made the same.

8. The high-frequency induction heating head according to claim 1, wherein the core is formed of a ferrite material, and the protection plate is formed of a copper material or an aluminum material.

9. The high-frequency induction heating head according to claim 1, wherein a heat-conducting grease is present between the core and the protection plate.

10. The high-frequency induction heating head according to claim 9, wherein the heat-conducting grease is a silicone-based grease.

11. The high-frequency induction heating head according to claim 1, wherein the cooling unit is configured to make the coil tubular and to make cooling water flow inside the tube, and a portion of the tubular coil is thermally coupled to the protection plate via a heat-conducting member.

12. The high-frequency induction heating head according to claim 11, wherein a through shaft is held to the heat-conducting member, and the surface of the protection plate on the side opposite the core is in abutment with the heat-conducting member.

13. The high-frequency induction heating head according to claim 1, characterized in that An air supply unit that performs air cooling of the core and the protective plate is provided in the high-frequency induction heating head.

14. A high frequency induction heating device, characterized by comprising: Possessing: The high-frequency induction heating head according to any one of claims 1 to 13; and A holding unit that holds a heated body disposed in a magnetic gap portion of the high-frequency induction heating head.

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