Thermal processing apparatus

To provide a thermal processing apparatus where a projection area perpendicular to the axis of a sealing structure and attachment structure of heat radiation heater is decreased and a chamber volume is decreased. The apparatus has a chamber for accommodating a workpiece of a thermal processing object, the chamber having a partition wall for partitioning inside from outside of the chamber, a heat radiation heater disposed penetrating the partition wall, wherein the heater has a ring seal arranged on an outer peripheral surface of the extension section, and hermetically sealing the chamber, and a heat blocking plate arranged between the heat radiation unit and the ring seal in the axial direction of the glass tube, for blocking heat radiated from the heat radiation unit to the ring seal, the heat blocking plate having an inner peripheral surface fitting along the extension section.

TECHNICAL FIELD

The present invention relates to a thermal processing apparatus that performs thermal processing on a workpiece, and particularly relates to a thermal processing apparatus that performs thermal processing by heating a workpiece inside a chamber.

BACKGROUND ART

In the related art, as illustrated inFIG. 6, a heating apparatus300is known which has a glass tube301penetrating a hermetically sealed chamber310surrounding a workpiece200. In this apparatus, a sealing member304seals a portion between the chamber310and the glass tube301, and an infrared reflection film301ais formed on a surface of the glass tube301in a region corresponding to the sealing member304. Additionally, cooling air330is forced to flow and a filament lamp320is arranged inside the glass tube301(refer to PTL 1, for example, refer to claim 1 and FIG. 2).

PRIOR ART DOCUMENT

Patent Document

DISCLOSURE OF INVENTION

Problem to be Solved by the Invention

However, in the heating apparatus300of the related art, a projection area is large in a direction perpendicular to the axis of the glass tube301and the sealing member304, and the volume of the chamber310is obliged to be large. Therefore, a longer time is required to adjust the atmosphere inside the chamber310, and thus the heating apparatus cannot be excellent to be productive. The present invention is made in view of these problems, and an object thereof is to provide a thermal processing (heat treating) apparatus, a volume of a chamber of which is reduced by decreasing a projection area in a direction perpendicular to an axis of an attachment structure and a sealing structure of a heat radiation heater.

Means for Solving the Problem

To achieve the above problem, a thermal processing apparatus of the first aspect of the invention100comprises, as shown inFIGS. 1, 2A and 2Bfor example, a chamber10for accommodating a workpiece200of a thermal processing object, the chamber10having a partition wall10afor partitioning an inside of the chamber from an outside of the chamber; a heat radiation heater20disposed penetrating the partition wall10a, wherein the heat radiation heater20has a heat radiation unit2for radiating heat to heat the workpiece200, and a cylindrical glass tube1covering the heat radiation unit2and having an extension section3extended outward beyond the heat radiation unit2in an axial direction; a ring seal4arranged on an outer peripheral surface3aof the extension section3, and hermetically sealing the inside of the chamber10from the outside of the chamber10, the ring seal4having an inner peripheral surface4acoming into contact with the outer peripheral surface3aof the extension section3; and a heat blocking (shielding) plate5arranged between the heat radiation unit2and the ring seal4in the axial direction of the glass tube1, for blocking (shielding) heat radiated from the heat radiation unit2to the ring seal4, the heat blocking plate5having an inner peripheral surface5dfitting along the extension section3.

According to this configuration, as compared to the sealing structure of the heat radiation heater in the related art, the heat radiation heater can be with a decreased or small projection area in the direction perpendicular to the axis of the sealing structure (ring seal) of the heat radiation heater which hermetically seals (closes in an airtight manner) the inside of the chamber. Therefore, a productive and excellent thermal processing apparatus can be realized which accommodates the heat radiation heater having the same output in the size-decreased (size-reduced) chamber and which has high atmospheric adjustment efficiency. Additionally, even when multiple heat radiation heaters adjacent to each other are provided, the heat radiation heaters can be arranged more closely. Therefore, an excellent thermal processing apparatus can be realized which has high heating efficiency.

According to aspect (2) of the present invention, as shown inFIGS. 1 and 2Bfor example, the thermal processing apparatus100according to aspect (1), further comprises, a cooling block30for holding the heat blocking plate5, the cooling block30covering the extension section3and extending outward from the partition wall of the chamber10in the axial direction of the glass tube1, wherein the outer peripheral surface4bof the ring seal4hermetically seals coming into contact with the cooling block30.

When this configuration is adopted, the heat blocking plate and the ring seal can be efficiently cooled by the cooling block. Therefore, since a separating distance between the heat radiation unit and the ring seal and a separating distance between the heat radiation unit and the heat blocking plate can be small, the sealing structure of the heat radiation heater can be downsized in the axial direction. Therefore, the excellent thermal processing apparatus can be realized in which the downsized chamber is provided.

According to aspect (3) of the present invention, as shown inFIG. 1for example, the thermal processing apparatus100according to aspect (2), further comprises a cooling medium circulation device40efor cooling the cooling block30.

When this configuration is adopted, the ring seal and the heat blocking plate can be more efficiently cooled by a cooling medium (for example, water or air) via the cooling block. Accordingly, the separating distance between the heat radiation unit and the ring seal and the separating distance between the heat radiation unit and the heat blocking plate can be further decreased (reduced). Therefore, the sealing structure of the heat radiation heater can be further downsized in the axial direction. Accordingly, the excellent thermal processing apparatus can be realized in which the further downsized chamber is provided.

According to aspect (4) of the present invention, as shown inFIG. 3Afor example, the thermal processing apparatus100according to aspect 2 or 3, further comprises, a spacer block40having a through-hole40apenetrated therethrough by the cooling block30, the spacer block30being for positioning the heat radiation heater20for the workpiece200(seeFIG. 1) at a predetermined position, wherein the spacer block40is attached hermetically covering a through-opening10bhaving a larger opening area than the through-hole40aand the through-opening10bis formed on the partition wall10aof the chamber10, and wherein the cooling block30and the spacer block40are attached to each other being hermetically sealed.

When this configuration is adopted, the thermal processing apparatus can be disposed so as to efficiently heat the workpiece by arranging the through-hole of the spacer block through which the cooling block covering and supporting the heat radiation heater penetrates, at any optional position suitable for the heat radiation heater to heat the workpiece. Additionally, in contrast, the thermal processing apparatus can be provided so as to hermetically cover the through-opening formed in the partition wall of the chamber with the spacer block. Therefore, without preparing a dedicated chamber for each different arrangement of the heat radiation heaters, the heat radiation heaters can be arranged at any optional position suitable to heat the workpiece. Additionally, the arrangement of the heat radiation heaters could be quickly and easily changed. Therefore, the productive and excellent thermal processing apparatus can be realized which can efficiently perform thermal processing (heat treatment) on more various workpieces.

According to aspect (5) of the present invention, as shown inFIG. 4for example, the thermal processing apparatus100according to aspect (1), further comprises, a spacer block40having a through-hole40afor attaching the heat radiation heater20, the spacer block40being for positioning the heat radiation heater20at a predetermined position relative to the workpiece200(seeFIG. 1), wherein the spacer block40is attached hermetically covering a through-opening10bhaving a larger opening area than the through-hole40aand the through-opening10bis formed on the partition wall10aof the chamber10, and wherein the outer peripheral surface4b(seeFIG. 2B) of the ring seal4hermetically seals coming into contact with the inner peripheral surface40bof the through-hole40a.

When this configuration is adopted, even when the cooling block is not provided, similarly to the thermal processing apparatus according to aspect (4), the thermal processing can be efficiently performed on the workpiece by arranging the heat radiation heater in the through-hole disposed at any optional position of the spacer block. Therefore, without preparing a dedicated chamber for each different arrangement of the heat radiation heaters, the heat radiation heaters can be arranged at any optional position suitable to heat the workpiece. Additionally, the arrangement of the heat radiation heaters could be quickly and easily changed. Therefore, the productive and excellent thermal processing apparatus can be realized which can efficiently perform thermal processing on more various workpieces.

According to aspect (6) of the present invention, as shown inFIG. 2Afor example, in the thermal processing apparatus100according to any one of aspects 1 to 5, the heat blocking plate5is formed in a ring shape, and split into multiple components in such a way that the ring is split into multiple sections5a,5bby a split surface5eor surfaces in a radial direction.

When this configuration is adopted, even when the heat blocking plate is attached to the heat radiation heater whose end portions are widened by being pressed against and superimposed on each other flatways, the split heat blocking plate can be easily assembled in the direction perpendicular to the axis of the heat radiation heater. In this case, the assembly work is not required to carry out which causes the end portion in the axial direction of the widened glass tube to penetrate the through-hole of the integrally formed heat blocking plate. Additionally, the heat blocking plate is made to be split into the multiple components, and the heat blocking plate split into the multiple components can be respectively assembled by placing the inner peripheral surface along the outer peripheral surface of the extension section of the glass tube. The heat blocking plates split in this way can also prevent a temperature rise in the ring seal by blocking the heat for the ring seal in the axial direction.

According to aspect (7) of the present invention, as shown inFIG. 5for example, in the thermal processing apparatus100according to any one of aspects 2 to 4, the heat blocking plate5(seeFIG. 1for example) and the cooling block30(seeFIG. 1for example) are formed as an integral component30e.

When disposed in this way, heat transfer is improved by integrally forming the heat blocking plate and the cooling block, thereby enabling to perform more efficient cooling. Accordingly, the separating distance between the heat radiation unit and the ring seal and the separating distance between the heat radiation unit and the heat blocking plate can be further decreased. Therefore, the sealing structure of the heat radiation heater can be further downsized in the axial direction. Accordingly, the excellent thermal processing apparatus can be realized in which the further downsized chamber is provided.

Effect of the Invention

According to the present invention, a thermal processing apparatus, a volume of a chamber of which is decreased can be provided.

This application is based on the Patent Application No. 2012-213435 filed on Sep. 27, 2012 in Japan, the contents of which are hereby incorporated in its entirety by reference into the present application, as part thereof.

The present invention will become more fully understood from the detailed description given hereinbelow. The other applicable fields will become apparent with reference to the detailed description given hereinbelow. However, the detailed description and the specific embodiment are illustrated of desired embodiments of the present invention and are described only for the purpose of explanation. Various changes and modifications will be apparent to those ordinary skilled in the art on the basis of the detailed description.

The applicant has no intention to give to public any disclosed embodiment. Among the disclosed changes and modifications, those which may not literally fall within the scope of the patent claims constitute, therefore, a part of the present invention in the sense of doctrine of equivalents.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described hereinafter in detail with reference to the drawings. In each drawing, like numerals and symbols will be used for identical or like elements, and duplicate descriptions will not be repeated. The present invention is not limited to the embodiments described below.

Referring toFIG. 1, a soldering apparatus100will be described as a thermal processing apparatus according to a first embodiment of the present invention. The soldering apparatus100according to the present embodiment which is illustrated inFIG. 1is provided as an apparatus for very reliably soldering a circuit board200as a workpiece by replacing the atmosphere inside a chamber10with a reducing gas atmosphere. The circuit board200is configured to include a board and electronic components, and the electronic components are arranged on the board. The electronic components or the electronic component and a lead wire are soldered with each other. Hereinafter, in some cases, this soldering is simply referred to as “the circuit board200is soldered”. When the circuit board200is soldered in the reducing gas atmosphere, an oxide film can be prevented from being formed on a soldering joint surface, and the soldering can be very reliably performed through reduction removal of the formed oxide film.

In the present embodiment, the oxide film on the soldering joint surface can be removed without adding flux (reducing agent) which may inhibit the soldering depending on conditions to solder. When the flux is not added to the solder, the soldering can be more reliably performed. Additionally, when the flux is not added to the solder, a flux cleaning step of removing the flux by cleaning the circuit board200after the soldering is not required. Accordingly, efficient and productive soldering can be performed.

In the soldering apparatus100according to the present embodiment, air inside the sealed chamber10is first sucked and exhausted by using a vacuum pump (not illustrated) so as to obtain lower pressure than the atmospheric pressure (for example, approximately 50 mTorr to 1000 mTorr). Subsequently, hydrogen gas serving as reducing gas is injected into the chamber10so as to adjust the atmosphere inside the chamber10. Thereafter, the circuit board200is heated and soldered inside the chamber10in which the atmosphere is adjusted.

The soldering apparatus100includes a halogen heater20serving as a heat radiation heater which heats the circuit board200by means of heat radiation. In the soldering apparatus100according to the present embodiment, a plurality of halogen heaters (heat radiation heaters)20are arranged side by side in parallel with each other on the same plane (refer toFIG. 3A). This arrangement can downsize a sealing structure for sealing the halogen heater20(to be described in detail later), thereby allowing a significant advantageous effect to be accumulated. In this manner, the chamber10of the soldering apparatus100can be considerably downsized.

The halogen heater20is disposed by covering a tungsten-made heat radiation coil2serving as a heat radiation member with a cylindrical glass tube1made of quartz glass. The glass tube1is sealed after being filled with inert gas (for example, nitrogen, argon, or the like) and halogen gas (for example, iodine, bromine, or the like). The halogen heater20can be quickly heated and cooled by a halogen cycle between the halogen and the tungsten. Thus, the temperature of the heat radiation coil2can be as high as over 2700° C. within a few seconds after being energized. Therefore, the halogen heater20can quickly heat the opposing circuit board200by using the heat radiation transferred from the heat radiation coil2whose temperature has become high. Additionally, the halogen heater20can maintain a sufficiently long life of the tungsten coil thanks to the halogen cycle. Therefore, the excellent heat radiation heater can be realized which can quickly heat the circuit board serving as the workpiece and which is very economically productive.

The halogen heater20can heat the circuit board200facing the halogen heater20by using the heat radiation (including infrared radiation in a wide wavelength region from a near infrared wavelength region (approximately 0.75 μm to 4 μm) to a far infrared wavelength region (approximately 4 μm to 1 mm)). The halogen heater20is disposed at a fixed position away from the circuit board200, but can directly heat the circuit board200from the position. For example, the halogen heater20heats a soldering joint up to 220° C. to 400° C. In this manner, the halogen heater20can solder the circuit board200by heating the soldering joint up to the melting point of the solder or higher. For example, in a case of the soldering joint where the solder containing much lead as one of the components is to be used, the heating temperature for the soldering joint can be adjusted to 300° C.

The halogen heater20is disposed in a linear shape (rod shape) as illustrated. Distribution (heat radiation amount) of heat radiation from the halogen heater20can be realized as desired heat radiation distribution, for example, by changing distribution sparseness and denseness of the tungsten coil (heat radiation unit)2. In the present embodiment, the halogen heater20is disposed by changing the number of windings of the coil so that the density of the coil is low (sparse) (not illustrated) in the central portion of the halogen heater20whose temperature is likely to become high and the density of the coil is high (dense) in both end portions. When disposed in this way, the halogen heater20can, for example, uniformly heat the overall circuit board200, by changing the heat radiation distribution (heat radiation amount) depending on the mass (heat capacity) of the soldering joint, the surface area, and the required quality for soldering (for example, a degree of reliability). On the other hand, the halogen heater20can also be configured so that the distribution of heat radiation (heat radiation amount) from the halogen heater20is the heat radiation distribution (heat radiation amount) by which only the soldering joint at any optional portion of the circuit board200is intensively heated.

In the present embodiment, the circuit board200is arranged above the halogen heater20as illustrated. The halogen heater20is disposed so as to heat the circuit board200from below. The circuit board200may be arranged inside the chamber10by being placed on a support base for supporting the circuit board. The support base is made of a material having heat resistance and heat conductivity. When the circuit board200is heated by the heat radiation via the support base, the heat radiation from the halogen heater20can be uniformed by the support base, thereby enabling the circuit board200to be evenly and uniformly heated. Additionally, the outer surface of the half peripheral surface of the glass tube1which is not opposed to the circuit board200, that is, a part of the surface of the glass tube1surrounding the tungsten coil2of the halogen heater20, has a white ceramic paint1aapplied thereto in order to reflect the heat radiation radiated in a direction which is not opposed to the circuit board200toward the circuit board200. In this manner, a portion of the halogen heater20which is not opposed to the circuit board200to be soldered is disposed as a reflection surface1a. Accordingly, the heat radiation radiated toward the circuit board200to be soldered can be further increased. In this case, the circuit board200can be more efficiently heated.

The cylindrical glass tube1surrounding the tungsten coil2serving as the heat radiation unit of the halogen heater20has an extension section3which is extended outward beyond the tungsten coil2in the axial direction. A tungsten wire is disposed in a linear shape inside the extension section3. The reason is that the large amount of radiation due to resistance heating in the tungsten wire wound in a coil shape is prevented. In this manner, the tungsten wire inside the extension section3can be disposed so as to be different from the tungsten coil2, and can be disposed so that the extension section3has significantly decreased heat radiation from the conducting wire (tungsten wire) as compared to the heat radiation from the tungsten coil2. Therefore, in the extension section3, the temperature of an outer peripheral surface3aof the glass tube1can be lower than the temperature of the outer peripheral surface of the glass tube1surrounding the tungsten coil2.

The extension section3is disposed to extend from the tungsten coil2in the axial direction. Therefore, as the extension section3is extended outward beyond the tungsten coil2in the axial direction, the extension section3is separated or getting more away from the part of glass tube1surrounding the tungsten coil2. Therefore, the extension section3is less likely to receive heat transfer from the part of glass tube1surrounding the tungsten coil2. Additionally, as the extension section3is extended outward beyond the tungsten coil2in the axial direction, the extension section3is no longer opposed to or no longer faces (is offset by) the tungsten coil2, and thus is less likely to receive the heat radiation from the tungsten coil. Therefore, in the extension section3, the heat radiation and the heat transfer are less likely to raise the temperature.

Additionally, the halogen heater20is disposed penetrating a partition wall10awhich partitions the inside of the chamber10from the outside of the chamber10. In this case, both end portions of the halogen heater20penetrate the partition wall10aof the chamber. In other words, the outside beyond an O-ring4serving as a ring seal of the extension section3of the glass tube1(to be described in detail later) is located on the atmosphere side, and thus both end portions of the halogen heater20are extended outward beyond the chamber10which is open to the atmosphere. Therefore, heat spreads to the atmosphere from both end portions of the halogen heater20which is open to the atmosphere. Accordingly, the temperature of the outer peripheral surface3aof the extension section3can be further lowered. Additionally, when disposed in this way, an electrode and a terminal which are located at both end portions of the halogen heater20can be disposed outside the chamber10. Therefore, the electrode and the terminal of the halogen heater20can be prevented from being exhausted due to repeated heating and pressure reducing. Additionally, since both end portions of the halogen heater20are not accommodated inside the chamber10, the chamber10can be downsized in the axial direction of the halogen heater20.

The extension section3of the glass tube1has the O-ring4arranged as the ring seal which hermetically seals (sealing) the inside of the chamber10from the outside of the chamber10in such a way that an inner peripheral surface4a(refer toFIG. 2B) comes into contact with the outer peripheral surface3aof the extension section3. The O-ring4has a circular cross section and a planar shape, and is made of an elastic material having heat resistance (for example, Viton (registered trademark) which is fluorine rubber). The inner peripheral surface4aof the O-ring4is disposed so as to hermetically seal the halogen heater20penetrating the partition wall10aof the chamber by directly coming into contact with the outer peripheral surface3aof the glass tube1of the halogen heater20. Accordingly, the O-ring4can be formed with a decreased diameter of an outer periphery4b(refer toFIG. 2B). Therefore, the halogen heater20can be disposed with a decreased projection area in a direction perpendicular to the axis of sealing structure.

A heat blocking plate5is disposed at a position in the axial direction of the halogen heater20between the tungsten coil2and the O-ring4. The heat blocking plate5is for blocking or shielding the heat radiation radiated in the axial direction of the halogen heater20from the tungsten coil2toward the O-ring4so as to prevent the temperature of the O-ring4from being raised. An inner peripheral surface5d(refer toFIG. 2A) of the heat blocking plate5is formed along the outer peripheral surface3aof the extension section3of the glass tube1. Accordingly, the heat radiation in the axial direction of the halogen heater20can be effectively blocked. Therefore, the O-ring4can be arranged to be close to the tungsten coil2in the axial direction of the halogen heater20. Accordingly, the soldering apparatus100according to the present embodiment can be formed with a decreased internal volume of the chamber10.

As in the present embodiment, it is preferable to dispose the heat blocking plate5so that the heat is not directly transferred from the heat blocking plate5to the O-ring4by arranging the heat blocking plate5to be separated from the O-ring4. Additionally, it is preferable to dispose the heat blocking plate5and the O-ring4so that the heat is less likely to be transferred by arranging the heat blocking plate5and the O-ring4with other component(s) for hindering the heat transfer (alternatively, multiple discontinuous surfaces (heat transfer surfaces) for reducing heat conductivity) therebetween. However, as will be described in detail later, when the heat blocking using heat reflection by the heat blocking plate5or the heat blocking using heat absorption and cooling functions sufficiently, the heat blocking plate5and the O-ring4may be disposed by bringing both of these into direct contact with each other.

The heat blocking plate5is made of stainless steel which is excellent in heat resistance and relatively good in insulation. When the heat blocking plate5is made of the stainless steel which is good in insulation, the O-ring4can be suitably blocked from the heat. Additionally, it is preferable to perform surface treatment at least on a reflection surface5c(refer toFIG. 2A) of the heat blocking plate5which faces the halogen heater20in the axial direction, with a material having higher reflectivity than the stainless steel as a base material. Typically, nickel plating or chromium plating can be performed on the surface of the stainless steel. In this way, the reflectivity of the reflection surface5ccan be improved. In this manner, the O-ring4can be blocked and protected from the heat in the axial direction of the halogen heater20by reflecting the heat radiation in the axial direction from the tungsten coil2.

As described above, the O-ring4is blocked from the heat radiated from the tungsten coil2by being arranged based on a positional relationship (by being separated and offset) in the extension section3of the glass tube1. Furthermore, the heat blocking plate5blocks the heat radiation radiated from the tungsten coil2in the axial direction of the halogen heater20, thereby enabling the O-ring4to be more effectively blocked from the heat. In the soldering apparatus100according to the present embodiment, the present inventor has confirmed that the temperature of the outer peripheral surface3aof the extension section3of the glass tube1for arranging the O-ring4therein can be approximately 150° C. or lower. Therefore, even when the O-ring4is directly disposed on the outer peripheral surface3aof the extension section3of the glass tube1, the halogen heater20can be disposed with the sealing structure downsized in the direction-perpendicular to the axis of the heater, without causing the O-ring4to suffer from thermal breakdown. Therefore, the soldering apparatus100which accommodates the same halogen heater20can be disposed with the decreased internal volume of the chamber10. Accordingly, the productive and excellent soldering apparatus can be realized which has high atmospheric adjustment efficiency.

As described above, various methods have also been attempted by which the heating apparatus300(refer toFIG. 6) in the related art is disposed with an internal volume of the chamber310(refer toFIG. 6) made as small as possible. However, it was difficult to downsize the sealing structure for hermetical sealing. The reason is that the sealing structure is caused to suffer thermal breakdown if the downsizing is forcibly made. Additionally, the fact that the sealing structure of the filament lamp320cannot be downsized is a major reason why the internal volume of the chamber310of the heating apparatus300cannot be downsized. The soldering apparatus100serving as the thermal processing apparatus according to the present invention solves this problem. The multiple halogen heaters20can be arranged more closely by arranging the multiple halogen heaters20so as to be adjacent to each other as in the soldering apparatus100according to the present embodiment (for example, refer toFIG. 3A). Therefore, the productive and excellent soldering apparatus can be realized which has high heating efficiency (heating density) for the circuit board200.

Furthermore, the soldering apparatus100according to the present embodiment includes the cooling block30which holds the heat blocking plate5, covers the extension section3of the glass tube1, and extends outward from the partition wall10aof the chamber in the axial direction of the glass tube1. The cooling block30has large heat capacity (mass), and extends outward from the chamber partition wall10a. The O-ring4is disposed so that the outer peripheral surface4b(refer toFIG. 2B) comes into contact with the cooling block30for hermetical sealing. Therefore, the cooling block30can suitably cool the O-ring4. Similarly, the heat blocking plate5is directly fixed to the cooling block30by means of screw fastening. Therefore, the cooling block30can cool the heat blocking plate5and the O-ring4at the same time. Additionally, the cooling block30is made of stainless steel which is good in insulation. Therefore, the heat radiation (heat reflection) from the inside of the chamber10can be blocked through various reflection routes, and the heat can be more suitably blocked for the extension section3and the O-ring4of the glass tube1covered with the cooling block30.

In this manner, the cooling block30cools the heat blocking plate5and the O-ring4, thereby enabling the heat blocking plate5and the O-ring4to be arranged to be closer to the tungsten coil2in the axial direction of the halogen heater20. Accordingly, the sealing structure of the halogen heater can be downsized in the axial direction. Therefore, the productive and excellent soldering apparatus100can be realized in which the internal volume of the chamber10is further decreased and which has high atmospheric adjustment efficiency.

The cooling block30is disposed so as to be forcibly cooled by using a cooling medium circulation device40efor circulating cooling water serving as a cooling medium which cools the cooling block30. The cooling block30is assembled into a through-hole40a(refer toFIG. 3A) formed in a spacer block40(to be described in detail later), and is attached to an inner diameter40bof the through-hole40aby being hermetically sealed using hermetical seals30aand30b. Therefore, the cooling medium circulation device40ecirculates the cooling water inside a cooling medium flow path40dformed in the spacer block40, thereby enabling the cooling block30to be cooled forcibly.

In a case where the cooling block30is forcibly cooled, as compared to a case where the cooling block30is naturally cooled, cooling or heat blocking for the heat blocking plate5and the O-ring4can be performed more efficiently. Therefore, the heat blocking plate5and the O-ring4can be arranged to be closer to the tungsten coil2in the axial direction of the halogen heater20. Accordingly, the sealing structure of the halogen heater can be further downsized in the axial direction. Therefore, the productive and excellent soldering apparatus100can be realized in which the internal volume of the chamber10is further decreased and which has high atmospheric adjustment efficiency.

Referring toFIGS. 2A to 2C, the soldering apparatus100serving as the thermal processing apparatus according to the present embodiment will be described in detail.FIG. 2Aillustrates the heat blocking plate5when viewed from the inside (inside of the chamber10) in the axial direction of the halogen heater. The heat blocking plate5is formed in a ring shape as a whole, but the ring is split into two sections of a first split component5aand a second split component5bby a split surface5e. In the halogen heater20according to the present embodiment, halogen gas serving as functional gas is filled inside the glass tube1. Therefore, end portions in the axial direction of the cylindrical glass tube1of the halogen heater20are widened by being hot-pressed against and superimposed on each other flatways, thereby forming a flat portion3b(refer toFIG. 2B). The flat portion3bhas a width larger than a cylindrical outer diameter of the halogen heater20. Therefore, by splitting the heat blocking plate5into the two components5aand5b, the inner peripheral surface5dof the heat blocking plates5aand5bcan be aligned with and assembled to the outer peripheral surface3aof the extension section3of the glass tube1having the flat portion3b. The heat blocking plates5aand5bwhich are split in this way can also prevent a temperature rise in the O-ring4by blocking the heat for the O-ring4in the axial direction. The heat blocking plate5can be typically split into two sections, but may be split into three sections, four sections, or any other optional number of sections.

The glass tube1cannot always be produced so as to have a constant thickness (diameter). Since the O-ring4is elastic, a serious problem does not occur. However, in a case of the heat blocking plate5formed of a metal plate, variations in the thickness (diameter) of the glass tube1can cause a problem. In order to align the inner peripheral surface5dof the heat blocking plate5with the outer peripheral surface3aof the glass tube1, as illustrated, the inner peripheral diameter of the inner peripheral surface5dof the heat blocking plate5may be first produced so as to be the maximum possible inner peripheral diameter which allows the variations in the diameter of the glass tube1. Then, in accordance with the outer diameter of the glass tube1which is used in practice, a half-split surface (split surface5e) may be cut so as to adjust the depth of the inner peripheral surface from the half-split surface. Additionally, several types of the heat blocking plate5may be prepared within the manufacturing error of the glass tube1, and the heat blocking plate5may be used by being selected from the several types.

FIG. 2Billustrates an enlarged adjustment side cooling block30-1, one of the two cooling blocks30illustrated inFIG. 1. The cooling block30-1is sealed with a hermetical seal30b, and is attached to a spacer block40-1. The attachment position of the hermetical seal30bis adjusted by an adjustment plate30c. A stationary side cooling block30-2sealed with the other hermetical seal30a(refer toFIG. 1) does not have the adjustment plate30c, and is fixed and assembled to a spacer block40-2. When the adjustment side and the stationary side are not particularly distinguished from each other, all are simply referred to as the cooling block30and the spacer block40. Additionally, similarly to the above-described O-ring4, the hermetical seals30aand30bcan be respectively made of an elastic material having heat resistance (for example, Viton (registered trademark) which is fluorine rubber).

Here, the glass tube1of the halogen heater20is molded by means of hot processing, and is made so that the flat portion3bis sealed in a state where the inside of the glass tube1is filled with inert gas. Accordingly, the glass tube1cannot always be manufactured accurately as a straight tube. Therefore, it is desirable to dispose a structure for absorbing variations (manufacturing error) in the attachment position which result from bending of the glass tube1. In the present embodiment, based on the attachment position of one stationary side cooling block30-2, the attachment position of the other adjustment side cooling block30-1is adjusted. Therefore, the inner diameter of the through-hole40aof the spacer block40-1to which the adjustment side cooling block30-1is attached is set to be larger than the outer diameter of the cooling block30-1to be assembled by an amount of the adjustment width. On the other hand, the attachment hole for attaching the cooling block30-1formed in the adjustment plate30cdoes not include the adjustment width, and is formed to have a fittable size to substantially coincide with the outer diameter of the cooling block30-1.

Here, the meaning of substantial coincidence is that both of these coincide with each other so as to be reasonably or snugly fitted well to each other. In other words, both of these coincide with each other to such an extent that both of these are reasonably fitted to each other using a sufficiently smaller clearance as compared to the adjustment width. Therefore, whereas, the adjustment plate30cis fitted to the cooling block30-1without any substantial clearance, the cooling block30-1and the adjustment plate30cwhich are fitted into each other can be moved relatively to the spacer block40-1for position adjustment and can be attached thereto. Then, the adjustment plate30cis screwed and fastened to the spacer block40-1by using two bolts for positioning. Thereafter, the cooling block30-1may be firmly fastened to the spacer block40-1by further using four bolts so as to have air-tightness. The position adjustment can also be performed by suitably utilizing a fastening margin of the screw (bolt) fastening. In this manner, when an adjustment structure (adjustment plate30c) for performing the position adjustment for the attachment position so as to align with the bending of the glass tube1is disposed, there is no possibility that an excessive force is applied to the glass tube1for the attachment. Therefore, the glass tube1can be prevented from being damaged or from losing air-tightness due to the excessive force applied to the seal.

In the present embodiment, furthermore, two back-up rings4care assembled on the inner side and the outer side in the axial direction between which the O-ring4is interposed in the axial direction of the halogen heater20so as to perform good airtight sealing by adjusting the external force applied to the O-ring4to be a uniform external force. Therefore, the two back-up rings4care disposed so as to adjust a deformation amount of the O-ring4to be a uniform deformation amount. In this manner, the O-ring4is interposed in the axial direction between the two back-up rings4c. Accordingly, the O-ring4can improve the air-tightness of the seal between the glass tube1and the cooling block30. The back-up rings4care disposed so as to be screwed and fastened to the cooling block30together with the heat blocking plates5aand5b. Accordingly, a force for interposing the O-ring4between the back-up rings4ccan be optionally adjusted by changing the thickness of the back-up rings4c. Therefore, the air-tightness of the seal using the O-ring4can be optionally adjusted. Here, although the back-up rings4cmay employ a half-split ring similarly to the heat blocking plate, elastic single-split rings (C-rings with no clearance) may be used to expand in the axial direction. In this manner, the back-up rings4cmay be assembled to the glass tube1.

FIG. 2Cillustrates the halogen heater20serving as the heat radiation heater when viewed from the outside (outside of the chamber10) in the axial direction of the halogen heater. The adjustment side cooling block30-1and the adjustment plate30cwhich are described above are disposed so as to allow independent screw fastening and unfastening. Therefore, as described above, the adjustment plate30cis first screwed and fastened to the spacer block40-1, and then the cooling block30-1is screwed and fastened to the spacer block40-1, thereby enabling the halogen heater20to be attached without applying the external force in the direction perpendicular to the axis of the halogen heater20. Additionally, a pressing plate30dis screwed and fastened to the cooling plate30-1from the outside in the axial direction of the halogen heater20so that the halogen heater20is not moved in the axial direction, thereby allowing the halogen heater20to be attached.

Referring toFIGS. 3A and 3B, the soldering apparatus100serving as the thermal processing apparatus according to the first embodiment of the present invention will be described.FIG. 3Aillustrates an attachment structure of the halogen heater20serving as the heat radiation heater of the soldering apparatus100according to the present embodiment. As described above, the cooling block30is hermetically sealed with the hermetical seals30aand30b(refer toFIG. 1), and is fixed inside the through-hole40a(refer toFIG. 2B) of the spacer block40. Additionally, the spacer block40to which the cooling block30is attached is attached to the chamber10by causing the hermetical seal40c(refer toFIG. 1) to hermetically close a through-opening10b(refer toFIG. 3B) disposed on the partition wall10aof the chamber. Similarly to the above-described O-ring4, the hermetical seal40ccan be made of an elastic material having heat resistance (for example, Viton (registered trademark) which is fluorine rubber). In this case, when multiple types of the circuit board200(refer toFIG. 1) are present as a thermal processing object, multiple types of the spacer block40can be prepared and replaced with each other in accordance with the type of the circuit board200. The halogen heater20is attached to the cooling block30, and is further attached to the inside the through-hole40aof the spacer block40. Therefore, the halogen heater20can be arranged at any optional position by arranging the through-hole40aat a position for most efficiently heating the circuit board200.

In this case, as compared to a case where the halogen heater20is directly attached to the partition wall10aof the chamber which has some difficulties in the replacement, the halogen heater20can be easily arranged at a most suitable heating position depending on the circuit board200. Additionally, the arrangement of the halogen heater20can be changed within a short time in accordance with a change in the types of the circuit board200which is a thermal processing object to be thermally processed. Therefore, the soldering apparatus100can be a productive and excellent soldering apparatus which can efficiently solder various circuit boards200. The partition wall10aof the chamber and the spacer block40are made of stainless steel having relatively high insulating performance. In this case, not only the inside of the chamber10can be hermetically sealed, but also efficient soldering can be performed by insulating the inside from the outside of the chamber10.

As described above, the soldering apparatus100according to the present embodiment has a decreased or small projection area in the direction perpendicular to the axis of the halogen heater20. Here, the projection area in the direction perpendicular to the axis means a projection area when viewed from above in the drawing. That is, in a case of the configuration according to the present embodiment where the multiple halogen heaters20are arrayed side by side, the projection area means a projection area including the sealing structure of the halogen heater20when viewed in a direction vertical to a plane where the multiple halogen heaters20are arrayed side by side. Here, a halogen heater assembly is configured to include the O-ring4(refer toFIG. 1) and the heat blocking plate5(refer toFIG. 1). In addition, the halogen heater assembly has also a decreased or small projection area of the halogen heater assembly which includes the sealing structure when viewed from the front side in the drawing. Additionally, the O-ring4of the halogen heater20is disposed to be close to the tungsten coil2(refer toFIG. 1) inward in the axial direction of the halogen heater. Therefore, the soldering apparatus100is with a decreased or small internal volume of the chamber10. The soldering apparatus100is a productive and excellent soldering apparatus which has high atmospheric adjustment efficiency. For example, comparing the time required to achieve vacuum by evacuating the atmosphere in the chamber10of the soldering apparatus100with that of the soldering apparatus in the related art, the present inventor has confirmed a very huge advantageous effect in that the time for the vacuum replacement can be reduced by 40%.

Even when the multiple halogen heaters20are disposed to be adjacent to each other, in the soldering apparatus100according to the present embodiment the multiple halogen heaters20can be closer to each other. Therefore, the circuit board200can be efficiently heated by using higher density of the heat radiation. Accordingly, since high heating efficiency is provided, the soldering apparatus100can be a productive and excellent soldering apparatus. Additionally, even when the multiple types of the circuit board200are soldered, the arrangement of the halogen heater20can be changed within a short time by replacing as required the spacer block40disposed depending on the circuit board200. Therefore, the soldering apparatus100can be a productive and excellent soldering apparatus which can efficiently perform thermal processing on the various circuit boards200.

Referring toFIG. 4, the soldering apparatus100serving as a thermal processing apparatus according to another embodiment of the present invention will be described. In another embodiment, the cooling block30(refer toFIG. 3A) and the spacer block40which are described above may be disposed integrally. In this case, the above-described heat blocking plate5(refer toFIG. 1) can be directly fixed to the inside of the spacer block40(inside of the chamber10) by means of screw fastening, and the O-ring4can be disposed so as to seal by directly bringing the outer peripheral surface4b(refer toFIG. 2B) of the O-ring4(refer toFIG. 1) into contact with the through-hole40aof the spacer block40. This embodiment is easily applied to a case where the above-described flat portion3b(refer toFIG. 2) is not formed in both end portions of the halogen heater20. In this case, the soldering apparatus100can be more easily provided.

Referring toFIG. 5, a soldering apparatus100aserving as a thermal processing apparatus according to a second embodiment of the present invention will be described. The soldering apparatus100ais provided similarly to the soldering apparatus100according to the first embodiment of the present invention except that the heat blocking plate5(refer toFIG. 1) and the cooling block30(refer toFIG. 1) are integrated with each other so as to be disposed as a cooling block30e. Accordingly, in the present embodiment, only the cooling block30ewill be described. In the cooling block30e, an inner groove is formed in order to assemble the O-ring4to the inner surface of the through-hole surrounding the halogen heater20. The O-ring4is assembled to the inner groove of the cooling block30eand the heat is blocked by a heat blocking plate section30fof the cooling block30efacing in the axial direction of the halogen heater20. Therefore, similarly to the case of the above-described heat blocking plate5, the heat can be suitably blocked for the O-ring4. On the other hand, as compared to a case where the heat blocking plate5and the cooling block30are independently disposed as described above, the integrally disposed cooling block30ecan efficiently transfer the heat, and can cool the heat blocking plate section30ffacing in the axial direction of the halogen heater. Therefore, in the soldering apparatus100aaccording to the present embodiment, the O-ring4can be disposed at a further inner side position in the axial direction of the halogen heater20(position closer to the tungsten coil2) as compared to the soldering apparatus100according to the above-described first embodiment.

Therefore, the soldering apparatus100aaccording to the present embodiment can be provided with the further decreased internal volume of the chamber. In this manner, the soldering apparatus100acan be an excellent soldering apparatus which has high atmospheric adjustment efficiency. This embodiment is also more easily applied to a case where the above-described flat portion3b(refer toFIG. 2B) is not formed at both end portions of the halogen heater20. Additionally, similarly to the cooling block30-1(refer toFIG. 1) of the soldering apparatus100(refer toFIG. 1) according to the first embodiment, the soldering apparatus100ahas an adjustment structure for adjusting an attachment position of a cooling block30e-1. Therefore, an external force for attaching the halogen heater20can be prevented from being applied to the O-ring4, thereby enabling the chamber10to be sealed in an improved airtight manner. Therefore, the soldering apparatus100acan be provided as a revolutionary soldering apparatus which is reliable in production and is economically excellent in production in view of maintenance of the O-ring4.

In the soldering apparatus according to the above-described embodiments, a case has been described where the soldering is performed by replacing the inside of the chamber10with the reducing gas atmosphere. However, in another embodiment, the soldering may be performed by simply exhausting the air from the inside of the chamber10by using a vacuum pump. In this case, the soldering can be more easily performed, preventing an oxide film from being formed on a soldering joint surface. Alternatively, in further another embodiment, the soldering may be performed, using formic acid gas as the reducing gas in place of hydrogen gas. In this case, the soldering can also be performed very reliably, similarly removing the oxide film formed on the soldering joint surface.

In the soldering apparatus according to the above-described embodiments, a case has been described where the halogen heaters20serving as the multiple heat radiation heaters are arranged side by side in parallel with each other on the same plane. However, in another embodiment, the soldering apparatus may include only one halogen heater20. In this case, similarly, the soldering apparatus can also be disposed with the decreased internal volume of the chamber by downsizing the sealing structure for sealing the halogen heater. Accordingly, the excellent soldering apparatus can be realized which has high atmospheric adjustment efficiency. Additionally, in the soldering apparatus according to the above-described embodiments, a case has been described where the circuit board200is heated from below with the circuit board200arranged above the halogen heater20. However, in another embodiment, the circuit board200may be directly heated from above using the halogen heater20with the circuit board200arranged below the halogen heater20. In this case, the circuit board200can also be directly heated. Accordingly, the soldering apparatus can be realized which has excellent heating efficiency. Additionally, the support base in a case of supporting the circuit board200may be made of any optional material having heat resistance and heat conductivity, for example, such as stainless steel, copper (copper alloy), aluminum (aluminum alloy), and ceramics. The stainless steel is advantageously used in that the stainless steel is excellent in heat resistance and is less likely to be oxidized. The copper and the aluminum can efficiently heat the circuit board200since both of them have higher heat conductivity than the stainless steel. Furthermore, carbon steel may be used. When the support base is arranged below the halogen heater20, it is not necessary to consider the heat conductivity. Accordingly, ceramics formed of quartz and the like having high heat resistance may be used.

Additionally, a case has been described where the heat radiation heater according to the above-described embodiments is the halogen heater20. However, in another embodiment, the heat radiation heater may be a carbon heater20which is filled with carbon fiber filaments in inert gas. In this case, the carbon heater20can radiate more infrared rays in a wavelength range of approximately 2 μm to 4 μm close to a peak (wavelength of approximately 3 μm) of a water absorption spectrum. Typically, the circuit board200as the workpiece contains moisture a little (electronic components and boards of a semiconductor package generally have some moisture-absorption characteristics). Therefore, the carbon heater20as the heat radiation heater can efficiently heat the circuit board200through the moisture contained in the circuit board200. Then, the moisture can be removed quickly. In further another embodiment, the heat radiation heater may be provided as a Nichrome wire heater in which air is filled and Nichrome filaments are placed. In this case, the heat radiation heater can be more easily provided.

Additionally, a case has been described where the outer surface of the half peripheral surface of the glass tube1(refer toFIG. 1) which surrounds the tungsten coil2(refer toFIG. 1) of the halogen heater20according to the above-described embodiments has the reflection surface1a(refer toFIG. 1) which the white ceramic paint1aapplied to and reflects the heat radiation radiated in the opposite direction to the circuit board200(refer toFIG. 1), toward the circuit board200. However, in further another embodiment, the reflection surface1adisposed on the half peripheral surface of the glass tube1which surrounds the tungsten coil2may be formed by partially performing vacuum deposition (plating) on the glass tube1made of quartz glass by using other material such as chromium which has high reflectivity and heat resistance. Alternatively, in further another embodiment, instead of the chromium (plating), the reflection surface1amay be formed of zirconium (plating) which similarly has high reflectivity and heat resistance.

Additionally, a case has been described where the O-ring4and the hermetical seals30a,30b, and40c(refer toFIG. 1for each) according to the above-described embodiments are made of fluorine rubber having heat resistance. However, in another embodiment, the O-ring4and the hermetical seals30a,30b, and40cmay be made of synthetic rubber (for example, silicone rubber) having desired air-tightness and heat resistance.

Additionally, a case has been described where the heat blocking plate5(refer toFIG. 1) and the cooling blocks30and30eaccording to the above-described embodiments are made of stainless steel which is relatively good in insulation. However, when the cooling blocks30and30eare sufficiently cooled (forcibly cooled), the heat blocking plate5and the cooling blocks30and30emay be made of an aluminum alloy which has high heat conductivity. In this case, the heat blocking plate5and the cooling blocks30and30eefficiently perform heat absorption and heat transfer. Accordingly, the heat can be blocked for the O-ring4(refer toFIG. 1). Additionally, a case has been described where the reflection surface5c(refer toFIG. 2A) of the heat blocking plate5according to the above-described embodiments is subjected to nickel plating or chromium plating in order to improve reflectivity. However, in another embodiment, without the reflection surface5cof the heat blocking plate5being subjected to metal plating, instead of the metal plating, the reflection surface5cmay be mirror finished through a polishing process. In this case, the reflection surface5ccan be provided more easily.

Additionally, a case has been described where the cooling medium circulation device40e(refer toFIG. 1) according to the above-described embodiments circulates water serving as a cooling medium inside the cooling medium flow path40d(refer toFIG. 1) disposed in the spacer block40. However, in another embodiment, instead of the water, the cooling medium circulation device40emay circulate air so as to cool the cooling block30. In this case, the cooling medium circulation device40ecan be prevented from being stained and easily handled.

In the above-described embodiments, a case has been described where the thermal processing apparatus is the soldering apparatus. However, in the other embodiments, the thermal processing apparatus can be any optional thermal processing apparatus which perform thermal processing by heating a workpiece. For example, the thermal processing apparatus can be a thermal processing apparatus which performs thermal processing on a workpiece in a certain atmosphere inside a chamber for producing semiconductor integrated circuits and to form films by PVD or CVD.

DESCRIPTION OF REFERENCE NUMERALS AND SYMBOLS