JP2012243955A - Batch-type local heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a batch-type local heating device capable of uniformly heating the whole of a target to be heated such as a printed circuit board when heating the target to be heated to solder it through the use of an induced current.SOLUTION: A batch-type local heating device comprises: a tube-like susceptor 6 with a plane on which a printed circuit board 1 as a target to be heated is placed; an induction coil 3 installed within the tube-like susceptor and having a linear portion 3c longer than the target to be heated which runs parallel with a planar portion 6a of the susceptor; a temperature sensor 4; and control means 5 which controls the heating amount of the susceptor while adjusting an AC current to be supplied to the coil according to the temperatures sensed by the temperature sensor.

Description

  The present invention relates to a collective local heating device used when heating and soldering an object to be heated (object to be heated) such as a printed wiring board.

  Conventionally, hot-air reflow or the like is generally employed as a heating device used when heating and soldering an object to be heated such as a printed wiring board. In addition, electronic parts are getting smaller and thinner, and parts without heat resistance are increasing. However, since heating devices such as hot air reflow are based on a batch heating method, they all perform the same heating on the object to be heated. Therefore, electronic components that are not heat resistant are damaged by heat. Therefore, it is difficult to optimally heat and solder to-be-heated objects having different heat resistances with current batch heating type apparatuses.

  Examples of such weak heat-resistant parts include a small camera module for mobile devices.

  On the other hand, mounting by a connector (see Patent Document 1) has been proposed as a method corresponding to the component side. However, as a problem, there is a problem that a connector or both a cable and a connector must be prepared, and the number of parts increases. In addition, after mounting the connector on the board, a process of incorporating the camera module is required, and there is a problem that it cannot be said that the efficiency of assembly is sufficient and causes a cost increase.

  Therefore, a method using induction heating has been proposed as a method to devise on the mounting side with respect to mounting of a weak heat-resistant component. In the conventional example (refer to Patent Document 2), as shown in FIG. 10, a pallet (this pallet is a substrate support table and a printed circuit board 111 is installed and continuously transported along a transport path at a predetermined speed. The pallet is also referred to as a flat susceptor 112), an induction coil 113, a temperature detection means 114, and the temperature detection means 114. Control means 115 for controlling the heating amount of the planar susceptor 112 while adjusting the alternating current supplied to the coil 113 according to the detected temperature.

  Prior to the installation of the printed wiring board 111, the operation of the conventional example is performed in such a manner that the surface temperature of the planar susceptor 112 is detected by the temperature detection means 114, and an alternating current is caused to flow through the coil 113 by the control means 115. The planar susceptor 112 is heated by electromagnetic induction and controlled to a predetermined temperature near the preheat temperature. Thereafter, the printed wiring board 111 is placed on the stage and preheated until a predetermined preheat temperature is reached.

  In the subsequent main heating step, in a state where the surface temperature of the flat susceptor 112 is detected by the temperature detecting means 114, an alternating current is passed through the coil 113 by the control means 115, and the flat susceptor 112 is heated to a predetermined main heating temperature. As a result, the solder 111b on the printed wiring board 111 whose temperature has been raised melts. After the main heating temperature is maintained for a predetermined time, the printed wiring board 111 is unloaded from the stage. After unloading, the solder 111b on the printed wiring board 111 is cooled and solidified, whereby the component 111a is fixed to the printed wiring board 111.

  Such a series of operations enables the mounting of weak heat-resistant components.

  Further, in order to make the temperature of the entire susceptor uniform, a technique such as winding a coil in a tunnel shape and passing a planar susceptor inside thereof is performed in Patent Document 3.

Japanese Patent No. 3799615 Japanese Patent No. 4282501 JP 2007-36110 A

  However, in the conventional configuration of induction heating in Patent Document 2, the portion (susceptor) through which the induced current flows is planar, so that a portion where the induced current does not flow is formed. Since the temperature of the part does not rise, as a result, the heating part becomes non-uniform in temperature, and there is a problem that soldering at a uniform temperature cannot be performed.

  In this regard, the cause will be described in a little more detail. Since the induced current is a current, it must go around according to Kirchhoff's law and return to the original location. If an attempt is made to take a current flow path around the planar susceptor without gaps, there will always be places where currents in opposite directions are adjacent. This is because the currents cancel each other and no current flows, and the temperature does not rise.

  Patent Document 3 is an example of solving this problem and soaking. In this example, thermal uniformity is realized by causing the induced current to make a round from the upper surface to the lower surface of the planar susceptor. However, since the substrate passes through the winding of the induction coil and a magnetic field is also applied to the substrate body, there is a problem that an induced current flows on the substrate and there is a concern about the influence on the electronic component. .

  The present invention solves the above-described conventional problems, and when heating an object to be heated such as a printed wiring board using an induced current and performing soldering, the entire object to be heated is uniformly heated. It aims at providing the collective local heating apparatus which enables.

  In order to achieve the above object, the present invention is configured as follows.

According to one aspect of the present invention, a cylindrical susceptor having a flat surface on which a printed wiring board to be heated is placed;
An induction coil disposed in the cylindrical susceptor and having a straight line portion longer than the object to be heated, and the straight line portion being parallel to the flat surface portion of the susceptor;
A temperature detector for detecting the temperature of the object to be heated;
There is provided a collective local heating device, comprising: a control unit that controls an amount of heating of the susceptor while adjusting an alternating current supplied to the coil in accordance with a temperature detected by the temperature detection unit.

  As described above, according to the collective local heating device of the present invention, when an object to be heated such as a printed wiring board is heated and soldered by using an induction current, the linear portion of the induction coil is longer than the object to be heated. And the straight part is parallel to the flat part of the susceptor, the magnetic field generated from the straight part of the coil is uniform in the flat part of the susceptor and is uniform in the flat part on which the object to be heated is placed. The induced current will flow. Accordingly, the heat generated by the induced current is also uniform, and the susceptor temperature is uniform.

  In addition, the amount of heat generated by the susceptor can be easily adjusted by the control means while detecting the temperature of the susceptor itself or a printed wiring board, which is an example of a heating target, by the temperature detecting unit. While maintaining the conditions, when mounting a component having low heat resistance, the temperature rise can be reliably suppressed below the specification limit, and only the portion that needs to be heated can be efficiently heated.

  In addition, because a heated object that can be heated by electromagnetic induction is placed in contact with the heating target, such as a printed wiring board, parts can be printed without placing unnecessary heat stress on printed wiring boards with low heat resistance components. It is possible to efficiently heat the joint part with and to improve the production quality.

The schematic perspective view of the package local heating apparatus in 1st Embodiment of this invention. 1 is a plan view of the collective local heating device of FIG. Front view of the batch local heating device of FIG. Right side view of the batch local heating device of FIG. The top view (analysis model figure) of the susceptor and induction coil concerning the Example of 1st Embodiment The right view (analysis model figure) of the susceptor and induction coil concerning the Example of 1st Embodiment The front view (analysis model figure) of the susceptor and induction coil concerning the Example of 1st Embodiment Figure of example (analysis result 1) of the first embodiment Plan view of susceptor and induction coil for electromagnetic field analysis model of plate-shaped susceptor as comparative example (analysis model diagram) Right side view of susceptor and induction coil for electromagnetic field analysis model of plate-shaped susceptor as comparative example (analysis model diagram) Front view of susceptor and induction coil according to electromagnetic field analysis model of plate-shaped susceptor as comparative example (analysis model diagram) Diagram of electromagnetic field analysis results of plate-shaped susceptor as a comparative example Plan view of susceptor and induction coil according to electromagnetic field analysis model when distance between susceptor and induction coil is changed Front view of susceptor and induction coil according to electromagnetic field analysis model of plate-shaped susceptor as comparative example Perspective view of susceptor and induction coil according to electromagnetic field analysis model of plate-shaped susceptor as comparative example Right side view of susceptor and induction coil according to electromagnetic field analysis model of plate-shaped susceptor as comparative example Diagram of electromagnetic field analysis results when the distance between the susceptor and the induction coil is changed The top view of the package local heating apparatus in 2nd Embodiment of this invention The front view of the package local heating apparatus in 2nd Embodiment of this invention The front view of the package local heating apparatus in the modification of 2nd Embodiment of this invention Figure of conventional local heating device

<First Embodiment>
In FIG. 1, the collective local heating apparatus in 1st Embodiment of this invention is shown.

  The collective local heating device includes a square cylindrical susceptor (portion through which an induction current flows) 6, an induction coil 3, a temperature measuring device 4 as an example of a temperature detection unit, and a control means (control unit) 5. It is composed.

  The rectangular cylindrical susceptor 6 has a flat surface portion 6a wider than the substrate 1 as an example of a heating target. The planar portion 6a of the susceptor 6 has a board 1 before soldering on which the circuit component 1a and the solder material 1b are placed (hereinafter, including the circuit component 1a, the solder material 1b, and the printed wiring board 1 as a whole to be heated). As an example, it is referred to as a workpiece W).

  The induction coil 3 is installed in the susceptor 6, is disposed in parallel with the flat portion 6 a of the susceptor 6, and has a straight portion 3 c that is longer than one side of the workpiece W. The straight portion 3 c of the susceptor 6 It is parallel to the flat portion 6a. AC power is applied to the induction coil 3 from the AC power source 33.

  The temperature measuring instrument 4 measures the temperature of the substrate 1.

  The control means 5 controls the AC power supply 33 based on the information from the temperature measuring device 4 to control the AC power applied to the induction coil 3.

  As shown in FIG. 1, the size (length and width) of the planar portion 6 a of the susceptor 6 is formed larger than the size (length and width) of the workpiece W. Further, the length of the linear portion 3 c of the induction coil 3 is formed longer than the length of the workpiece W. In addition, the space inside the cylindrical susceptor 6 is formed to be large enough to arrange the induction coil 3. The susceptor 6 is made of a magnetic material (for example, iron), and the induction coil 3 is made of a conductor material (for example, copper).

  The collective local heating device having the above-described configuration operates as follows.

  First, the workpiece W is placed on the cylindrical susceptor 6.

  Thereafter, the control means 5 applies an alternating current to the induction coil 3 via the alternating current power source 33. The induction coil 3 generates an alternating magnetic field by the energized alternating current. An induced current flows through the susceptor 6 by the induction action of the alternating magnetic field, and the susceptor 6 is heated by the current. Then, each solder material 1b on the board | substrate 1 mounted on the upper part of the susceptor 6 is heat-melted.

  Thereafter, when the solder material 1b is heated and melted, the control means 5 stops the supply of alternating current through the alternating current power source 33. The timing of stopping the energization of the alternating current is stopped on the assumption that the solder has melted after a certain time has elapsed after the temperature sensor 4 reaches a certain temperature.

  After stopping, the temperature of the solder material 1b heated and melted decreases, and the circuit component 1a on the workpiece W and the substrate 1 are fixed to each other with the solder material 1b. That is, it is soldered. The temperature measuring device 4 detects the temperature of the workpiece W and outputs information detected by the temperature measuring device 4 to the control means 5. Based on the detection information from the temperature measuring device 4, the control means 5 controls the alternating current that is passed through the induction coil 3 via the alternating current power supply 33 so that the workpiece W is not heated excessively.

  2A, 2B, and 2C show the three views of FIG. 1, that is, a plan view, a front view, and a right side view, respectively. The printed wiring board 1 is placed on the susceptor 6. On the printed wiring board 1, a circuit component 1a such as a semiconductor element or a capacitor or a resistor is placed via a solder material 1b.

  The circuit component 1a is arranged at various positions on the printed wiring board 1 depending on its circuit configuration. Depending on the arrangement of the circuit component 1a, the solder material 1b for soldering the circuit component 1a to the printed wiring board 1 is also arranged at various positions.

  The induction coil 3 is wound in a loop according to the direction along the square cylindrical surface of the susceptor 6 (the direction of the arrow X in FIG. 1). The loop is formed in a plurality of turns at substantially constant intervals in the direction in which the susceptor 6 forms a cylindrical hole (in the direction of arrow Y in FIG. 1), and the entire coil is wound in a spiral shape. By forming and arranging the induction coil 3 and the susceptor 6 in this way, the induction current generated in the susceptor 6 by the induction coil 3 flows uniformly along the surface constituting the square tube, as in the conventional example. No part where currents cancel each other out.

  Further, as described above, the coil 3 has a straight line portion 3 c longer than one side of the workpiece W, and the straight line portion 3 c and the flat surface portion 6 a of the susceptor 6 are arranged in parallel to each other. Due to such a configuration, the magnetic field generated from the straight portion 3c of the coil 3 is uniform in the flat portion 6a of the susceptor 6, and a uniform induced current flows in the flat portion 6a on which the workpiece W is placed. Become. Accordingly, the heat generated by the induced current is also uniform, and the temperature of the susceptor 6 is uniform. The susceptor temperature acts uniformly on the workpiece W placed on the flat surface portion 6 a of the susceptor 6. As a result, it is possible to uniformly heat and melt the solder material 1b arranged at various positions of the printed wiring board 1 which is an example of the workpiece W.

  The susceptor 6 does not necessarily have the same material and the same thickness as a whole. For example, the susceptor 6 is configured to be thicker than the flat portion 6a of the susceptor 6 used for soldering, to use a material with low resistance, or to magnetic If various configurations such as a configuration using a small material are employed, heat radiation from a surface that does not contribute to soldering can be reduced, and as a result, energy consumption of the collective local heating device can be reduced.

<Example 1>
Examples of the cylindrical susceptor 6 and the induction coil 3 in the first embodiment are shown by the results of three-dimensional electromagnetic field analysis. The three-dimensional electromagnetic field analysis used Ansoft HFSS (ver 11.0) (Ansys Japan Co., Ltd.).

  First, it will be described in detail that the induction heating action generated in the susceptor 6 by the induction coil 3 becomes uniform.

  3A to 3C are models in which the induction coil 3 and the susceptor of FIG. 1 are taken out.

  The cylindrical susceptor 6 has a shape in which four rectangular plates are combined in a cylindrical shape. A surface on which the workpiece W that is the substrate 1 to be soldered is placed is defined as a flat portion 6a. The induction coil 3 is wound in a loop according to the direction along the cylindrical surface of the susceptor 6. The coil 3 has a straight portion 3 c parallel to the flat portion 6 a of the susceptor 6. The coil 3 is wound in a spiral at substantially constant intervals. Further, AC power is applied from 3a and 3b, which are both ends of the induction coil 3, via an AC power source 33.

  In this embodiment, the dimensions of the susceptor 6 have a cylindrical shape with a long side of 484 mm, a short side of 242 mm, a thickness of 74 mm, a thickness of each cylindrical wall of 1 mm, and a hole in the short side direction. The material is iron. The induction coil 3 has a Φ6 mm line, two straight portions 3 c of 410 mm in length, separated by 40 mm in parallel, and connected with an arc between them to form a loop, which is wound in a spiral shape with a pitch of 8 mm for 25 turns. It is the composition which is. The material of the induction coil 3 is copper.

  The positional relationship between the susceptor 6 and the coil 3 is such that the flat portion 6a of the susceptor 6 and the straight portion 3b of the coil 3 are parallel and the distance between the conductors is 10 mm.

  Further, both ends 3 a and 3 b of the induction coil 3 are drawn out of the susceptor 6 and are supplied with AC power via an AC power supply 33.

  In FIG. 3A, the direction at a certain moment of the alternating current applied to the induction coil 3 via the alternating current power source 33 is indicated by a solid line arrow. In FIG. 3C, current flows through the upper straight portion 3c-1 of the induction coil 3 from the left side to the right side. Further, a current flows from the right side to the left side of the drawing in the lower straight line portion 3c-2.

  A magnetic field is generated by this current. The magnetic field generates a magnetic flux 100a in a counterclockwise direction so as to surround the entire line of the coil 3 located on the left side of FIG. 3B. Further, the magnetic flux 100b is generated in the clockwise direction so as to surround the entire induction coil wire located on the right side of FIG. 3B.

In the susceptor 6 arranged so as to surround the induction coil 3, when the magnetic flux density generated by the induction coil 3 is changed by the alternating magnetic field, an induction current is generated by the electromagnetic induction action. The direction is a direction in which the magnetic flux is generated so as to cancel the increase and decrease of the magnetic flux density.
For example, when the magnetic fluxes 100a and 100b generated by the induction coil 3 increase, an induced current 101 as shown in FIG. 3A is generated.

  In other words, as shown in FIG. 3A, an induced current flows through the susceptor 6 in the cylindrical longitudinal direction 101 along the coil 3.

  At this time, the magnetic field generated from the entire straight portion 3b of the induction coil 3 has a uniform pitch wound in a spiral, the same current value flows, and the current direction is aligned. Therefore, a uniform magnetic field is generated on a surface parallel to the flat portion 6a of the susceptor 6. For this reason, the flat surface portion 6a of the susceptor 6 is uniformly affected by the magnetic field from the straight portion 3b of the induction coil 3, so that a uniform induction current 101 is generated, and as a result, a uniform induction heating action is obtained. Become.

  FIG. 4 shows a result obtained by analyzing the induced current density distribution of the flat surface portion 6a of the susceptor 6 by the analysis in the embodiment of FIGS. 3A to 3C.

  In FIG. 4, the current density values are divided into five stages every 20% from 0 to the maximum value of the induced current density of the plane portion 6a. A region having a temperature of ± 10%, which is generally required in the soldering process, is a white portion in the center of FIG. 4, and a uniform temperature region as wide as about 60% with respect to the entire area of the susceptor 6 can be secured.

  FIG. 4 shows the distribution of induced current density, and the effect of further improving the soaking area can be obtained by the heat conduction effect of the susceptor 6.

  Next, as a comparative example of the first embodiment, an example will be introduced in which the induction heating effect cannot be obtained in the case of the susceptor 2 in which the shape of the susceptor 6 is not cylindrical but is a single plate. 5A to 5C show models of comparative examples.

  The susceptor 2 has a single plate shape with an outer shape of 484 mm long × 242 mm short and a thickness of 1 mm. The material of the susceptor 2 is iron as in the first embodiment (FIGS. 3A to 3C). The shape and material of the induction coil 3 are both the same as in the first embodiment. In other words, the configuration and the positional relationship of the first embodiment are substantially followed, and the susceptor is changed from a cylindrical shape to a single plate shape in which only the flat portion 6a on which the workpiece W is installed is left.

  FIG. 6 shows the result of the induction current density distribution on the plane 2a of the susceptor 2 obtained by electromagnetic field analysis.

  In FIG. 6, as in the first embodiment, the current density values are divided into five stages every 20% from 0 to the maximum value of the induced current density of the plane portion 2a.

  As can be seen from this result, the current is concentrated at the end portion and the soaking effect cannot be obtained. Also, the induced current value at the center of the susceptor 2 is about one-tenth that of the first embodiment, and the efficiency is very poor. This is because the susceptor 2 has a single plate shape, so that a circuit (flow path) through which an induced current flows is not formed and an induced current does not flow.

  Next, an example in which uniformization may be hindered by the distance or coil pitch between the susceptor 2 and the induction coil 3 will be introduced.

  7A to 7D show the model of the above example.

  The induction coil 13 has one turn for simplification. The linear portion 13c of the induction coil 13 was set to 100 mm, the interval between the linear portions 13c was set to 45 mm, the linear portions 13c were connected in an arc shape, and the material was copper. The susceptor 16 was made of iron having a thickness of 1 mm. Further, the planar portion 16a of the susceptor 16 has a size of long side 170 mm × short side 40 mm, and the distance from the induction coil 13 is changed from 2.5 mm to 12.5 mm every 2.5 mm pitch to obtain the induced current distribution. It was.

  FIG. 8 shows the result of the induced current density distribution of the flat portion 16a of the susceptor 16 obtained by electromagnetic field analysis. In the same manner as in Example 1, the current density values were painted in 5 steps every 20% from 0 to the maximum value of the induced current density on the same plane. 8A shows that the distance between the flat portion 16a of the susceptor 16 and the induction coil 13 is 2.5 mm, FIG. 8B shows the distance of 5.0 mm, FIG. 8C shows the distance of 7.5 mm, and FIG. Is the result when the distance is 10.0 mm, and (e) is the result when the distance is 12.5 mm.

  Further, as a standard for comparing the respective distribution charts, squares of the same size are written in FIG. 8 with dotted lines in the respective distribution charts. The vertical width is matched with the length of the linear portion 13c of the induction coil 13, and the horizontal width is 10 mm as a guide for the pitch between the linear portions 13c.

  As shown in FIG. 8, when the distance between the susceptor 16 and the coil 13 is close or far, the area where the induced current is uniform decreases. Further, the distance between the susceptor and the coil is 5 to 11 mm, more preferably 7.5 to 10 mm, which is a highly uniform region. Thus, even in the apparatus according to the first embodiment, the distance between the flat portion 6a of the susceptor 6 and the straight portion 3c of the coil 3 is 5 to 11 mm, and more preferably 7.5 to 10 mm. It turns out that it becomes.

  According to the collective local heating device according to the first embodiment of the present invention, when the object to be heated such as the printed wiring board 1 is heated and soldered by using the induced current, the induction coil 3 is moved from the object to be heated. Since the straight portion 3c has a long straight portion 3c and is parallel to the flat portion 6a of the susceptor 6, the magnetic field generated from the straight portion 3c of the coil 3 becomes uniform in the flat portion 6a of the susceptor 6, A uniform induced current flows through the flat portion 6a on which the printed wiring board 1 which is an example of the heating target is placed. Accordingly, the heat generated by the induced current is also uniform, and the temperature of the susceptor 6 is uniform.

  The amount of heat generated by the susceptor 6 can be easily adjusted by the control means 5 while detecting the temperature of the susceptor itself or the temperature of the printed wiring board 1 which is an example of the heating object. When a component with low heat resistance is mounted while maintaining a desired temperature increase condition, the temperature increase can be surely suppressed to a specification limit or less, and only a portion requiring heating can be efficiently heated.

  Further, since a heating object capable of electromagnetic induction heating is placed in contact with a heating target such as the printed wiring board 1, an unnecessary thermal stress is not applied to the printed wiring board 1 on which components having low heat resistance are mounted. Therefore, it is possible to efficiently heat the joint portion with the component, and the production quality can be improved.

Second Embodiment
9A and 9B show a collective local heating device according to the second embodiment of the present invention. In FIG. 9A, the temperature measuring instrument 4 should be illustrated so as to overlap the workpiece W, but the position is shifted in order to avoid complication of the drawing.

  The collective local heating device according to the second embodiment is a cylindrical susceptor 6 (hereinafter referred to as a susceptor) on which a circuit component 1a and a solder material 1b are placed and a substrate 1 before soldering is placed as a part having the same configuration as the first embodiment. ), An induction coil 3 wound inside the susceptor 6, a temperature measuring device 4 for measuring the temperature of the substrate, and a control means 5 for controlling them.

  Furthermore, in the collective local heating device according to the second embodiment, as a portion added to the first embodiment, a first conveyor (hereinafter referred to as the front conveyor 7) having a function of transporting and stopping the susceptor 6 from the previous process. , A second conveyor for holding the susceptor 6 and guiding it to the induction coil 3, in other words, a movable conveyor (hereinafter referred to as a movable conveyor 8), and a third conveyor having a function of stopping and transporting the susceptor 6 to the next process again. (Hereinafter referred to as rear conveyor 9). The front conveyor 7, the movable conveyor 8, and the rear conveyor 9 are controlled in operation by the control unit 5, and information from the previous process and the subsequent process is input to the control unit 5.

  The movable conveyor 8 is moved between the two positions A and B by the moving device 50 under the control of the control means 5. The positions include two positions: a position for transferring the front and rear conveyors 7 and 9 and the susceptor 6 (hereinafter referred to as a transfer position) A and a position where the induction coil 3 is provided (hereinafter referred to as a heating position) B. .

  According to the above configuration, first, the substrate 1 is placed on the flat portion 6a of the susceptor 6, the solder material 1b is supplied to the soldering portion of the substrate 1, and the pre-process for placing the component 1a to be soldered thereon is performed.

  Thereafter, the susceptor 6 on which the substrate 1 is placed is conveyed by the front conveyor 7 into the batch local heating apparatus. In the susceptor 6, the substrate 1 to be processed before the substrate 1 on the susceptor 6, that is, the substrate 1 previously placed on the movable conveyor 8 passes through the movable conveyor 8 and is conveyed to the rear conveyor 9. Until it is done, it is stopped on the front conveyor 7.

  After the front substrate 1 is transferred from the movable conveyor 8 stopped at the delivery position A to the rear conveyor 9, the susceptor 6 on the front conveyor 7 is transferred to the movable conveyor 8 stopped at the delivery position A.

  Next, the movable conveyor 8 is moved from the delivery position A to the heating position B by the moving device in the width direction of the movable conveyor 8, and the induction coil 3 is placed in the susceptor 6 at the heating position B.

  Next, according to the procedure of 1st Embodiment, it heats with the induction coil 3 and solders, and after completion, the movable conveyor 8 moves from the heating position B to the delivery position A again. At this time, the induction coil 3 is extracted from the susceptor 6.

  Next, at the delivery position B, the susceptor 6 is transferred from the movable conveyor 8 to the rear conveyor 9, and the movable conveyor 8 waits until the next susceptor 6 comes from the front conveyor 7. The back conveyor 9 stops the susceptor 6 until the back process is vacant, and is transported to the back process after the back process is vacant.

  By adopting the configuration of the second embodiment, there is no transfer of the printed wiring board 1 from the susceptor 6 until the printed wiring board 1 and the component 1a are fixed by the solder 1b and stabilized in strength. Soldering is possible.

  In the operation examples so far, the whole temperature process from preheating to main heating to cooling is performed at the heating position. However, as shown in FIG. 9C, a new induction coil 3 or lamp is placed on the front conveyor 7. Alternatively, by providing the hot air port 3H or a plurality of means among them, preliminary heating is performed by the front conveyor 7, and main heating is performed by the movable conveyor 8, so that the temperature process can be performed in parallel. In this case, the temperature process can be performed in parallel at each position, and the tact can be reduced as a whole apparatus.

  Alternatively, by providing a new induction coil 3 or lamp or cooling air port or a plurality of means among them on the rear conveyor 9, it is also possible to perform the temperature process in parallel. Also in this case, the temperature process can proceed in parallel at each position, and the tact can be shortened as a whole apparatus.

  In addition, it can be made to show the effect which each has by combining arbitrary embodiment or modification of the said various embodiment or modification suitably.

  The collective local heating device according to the present invention enables uniform heating of the entire object to be heated when performing soldering by heating the object to be heated such as a printed wiring board by using an induced current. This is useful when heating and soldering an object to be heated (object to be heated) such as a wiring board.

DESCRIPTION OF SYMBOLS 1 Printed wiring board 1a Parts 1b Solder material 2 Planar susceptor 3 Induction coil 3a Induction coil end 3b Induction coil end 3c Induction coil linear part 4 Temperature measuring device (temperature detection part)
5 Control means 6 Cylindrical susceptor 6a Flat part 7 Front conveyor 8 Movable conveyor 9 Rear conveyor 33 AC power supply 50 Moving device A Delivery position B Heating position W Workpiece

Claims (2)

A cylindrical susceptor having a flat surface on which a printed wiring board to be heated is placed;
An induction coil disposed in the cylindrical susceptor and having a straight line portion longer than the object to be heated, and the straight line portion being parallel to the flat surface portion of the susceptor;
A temperature detector for detecting the temperature of the object to be heated;
A batch local heating apparatus, comprising: a control unit that controls an amount of heating of the susceptor while adjusting an alternating current supplied to the coil according to a temperature detected by the temperature detection unit.   2. The collective local heating according to claim 1, wherein a distance between the planar portion on which the printed wiring board of the cylindrical susceptor is placed and the linear portion of the induction coil is 5 to 11 mm. apparatus.

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