JP2919816B2 - Pulse heating type bonding apparatus and its control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse heating type welding apparatus for locally heating and joining a joined portion by supplying a pulse current to a heater pressed against the joined portion,
It relates to the control method.

[0002]

2. Description of the Related Art Conventionally, a pulse heating method has been used as a joining apparatus used for thermocompression bonding of lead wires of a thick-film printed wiring board, a thin-film printed wiring board, and the like, and reflow soldering of IC leads and the like to a printed wiring board. Are known.

In this method, a heater chip made of a high-resistance material such as molybdenum (MO) is pressed against a portion to be joined, and in this state, a large pulse-like current flows through the heater chip to generate Joule heat. The joint is locally heated and melted by this heat, and joined. For example, in the case of reflow soldering, the solder sandwiched between a pair of parts to be joined is melted, and then the pulse current is stopped, and the parts to be joined are cooled and the temperature of the solder becomes equal to or lower than the solidification temperature of the solder. Part.

Accordingly, in this type of bonding apparatus, a head having lifting / lowering drive means for pressing or separating a heater chip from a part to be bonded, and a pulse current that changes in accordance with the heating time of the heater chip are generated. And a pulse heat power supply. In this case, the pulse heat power supply feeds back the temperature of the heater chip, that is, the heater temperature, and controls the heater current so that the heater temperature has a preset time / temperature control characteristic (referred to as a temperature profile).

That is, the phase of the heater current (AC) is controlled so as to reduce the difference between the target temperature obtained from the temperature profile and the feedback heater temperature, and the heater temperature follows the change in the target temperature.

[0006]

Heretofore, conventionally, the supply of the heater current is started while the heater chip is pressed against the portion to be joined at a constant pressure, and the heating is started. Therefore, the heater is pressed against the part to be joined even during the heating, and the amount of heat transmitted from the heater to the part to be joined and further to the object (work) such as an IC is increased. Depending on the work such as an IC, it is required to minimize the heating at the time of joining. However, in the conventional apparatus, since the amount of heat transmitted to the work is large, there is a problem that the reliability of a product incorporating the work is reduced. there were.

In a conventional apparatus, a heater is heated to a joining temperature while being pressed against a portion to be joined with a constant pressing force, and is maintained at a constant set temperature for a constant time. Therefore, for example, in the case of solder joining, a constant pressing force is applied from before to after the solder is melted, so that the molten solder is pushed out from between the portions to be joined to the periphery thereof. For this reason, not only the amount of solder remaining in the portion to be joined is reduced, but also the molten solder flowing out therearound may cause a short circuit. For this reason, there has been a problem that the reliability of bonding is reduced.

Accordingly, the present invention can set the pressing force suitable for the changing heater temperature to perform more precise and optimal bonding control, and to prevent the molten solder from flowing out from the bonded portion. A first object is to provide a suitable control method of a pulse heating type bonding apparatus.

Also, a control method of a pulse heat type joining apparatus is provided which prevents molten solder from flowing out of a portion to be joined and reduces the amount of heat transmitted to the portion to be joined to improve the reliability of solder joining. Is a second purpose.

Furthermore this invention is to provide a bonding apparatus used directly in the practice of these methods is a third object of.

[0011]

The first object, according to the present invention DETAILED DESCRIPTION OF THE INVENTION, together with heat by pressing the bonding portion by the heater, by feeding back the heater temperature to follow the temperature profile was set heater temperature in advance, the joint After heating and cooling
In the control method of using the data in the pulse heat type joining apparatus for joining Ri by the be separated from the welded portion, the lower limit temperature at which the heater temperature is set lower than the bonding temperature <br/> bonding portion which is set by the temperature profile Before reaching the heater
Pressing starts on the part to be joined, and then the heater temperature rises
The method of pulse heat type bonding apparatus according to claim Rukoto continue to push to decrease the pressing force against the bonding portion of the heater by detecting the arrival to the lower limit temperature Te is achieved by.

A second object is to set the heater temperature to the lower limit temperature.
Start pressed into contact with the bonding portion of the heater from reaching the lower other lower temperature can be achieved by reducing the pressing force of the heater by detecting the heater temperature reaches the minimum temperature.

[0013] The same object is achieved by a first-stage heating for heating the temperature profile to a first set temperature lower than the joining temperature of the joining portion and a second-stage heating for heating to a second set temperature higher than the first set temperature. while set to heat in two steps, to start the press contacting the heater bonding portion detects that the heater temperature reaches the first limit temperature lower than the first set temperature, the heater temperature is the This is achieved by detecting that a second lower limit temperature higher than the first set temperature and lower than the second set temperature has been reached and reducing the pressing force of the heater.

The same object is the case of single-stage heating in which the heater temperature rises substantially linearly from the start of heating to a set temperature higher than the bonding temperature.
This can also be achieved by setting a lower limit temperature, starting pressing the heater at the first lower limit temperature on the low temperature side, and reducing the pressing force at the second lower limit temperature.

Further, a third object is to press and heat the portion to be joined with a heater, feed back the heater temperature so that the heater temperature follows a preset temperature profile, and after heating and cooling, connect the heater to the portion to be joined. In the pulse heating type joining apparatus which is brought into contact with the heater by separating from the heater, the heater temperature detecting means for detecting the heater temperature, the temperature profile and the temperature profile are set by the heater.
Memory means for storing a lower limit temperature set lower than the joining temperature of the portion to be joined, determining means for detecting that the heater temperature has reached the lower limit temperature while the heater temperature is increasing, and outputting a determination signal; and Pressure adjusting means for changing the pressing force on the portion to be joined, and the determining means
Before the output, the heater is pressed against the portion to be joined.
And a pressing force control means for reducing the pressing force of the heater on the portion to be bonded based on the determination signal and continuing to press the heater.

In this case, the judgment means determines that the heater temperature is lower than the lower limit.
Detects that the lower limit temperature is reached
And the pressing force control means outputs another judgment signal.
The second object can be achieved by bringing the heater into contact with the portion to be joined and starting pressing based on the constant signal .
That is, the amount of heat transmitted to the work can be reduced , and the molten solder can be prevented from flowing out of the portion to be joined.

Further, the temperature profile is to be heated in two stages. When the heater temperature reaches the first lower limit temperature during the first stage heating, pressing of the heater is started, and during the second stage heating, the second lower limit temperature is started. If the pressing force of the heater is decreased when the temperature reaches the above, both the purpose of reducing the amount of heat transmitted to the work and preventing the flow of the molten solder can be achieved.

[0018]

[Action] If the heater starts to be pressed against the joint at the lower limit temperature lower than the joining temperature (solder melting temperature) of the joint, the time during which the heater is in contact with the joint is shortened, and the amount of heat transmitted to the work is reduced. Decrease. Further, when the heater is pressed before reaching the lower limit temperature, if the pressing force of the heater is reduced at the lower limit temperature, it is possible to prevent the molten solder from being pushed out of the part to be joined and flowing away.

Further, two kinds of lower limit temperatures (first and second lower limit temperatures) are set, and when the first lower limit temperature is reached, the heater is pressed against the portion to be joined, and when the second lower limit temperature is reached, the heater is pressed. If the pressure is reduced, it is possible to simultaneously protect the work and prevent the molten solder from flowing out.

[0020]

Embodiment

FIG. 1 is an external view of a bonding apparatus according to an embodiment of the present invention, FIG. 2 is a simplified view of a control system thereof, and FIG. 3 is a heater current waveform (a) and its zero cross signal (b). )
FIG. 3 is a diagram showing a reset signal R (c). FIG. 4 is a diagram showing a heater current detection circuit, and FIG. 5 is a display example of a display device. FIG. 6 is a functional block diagram of the control circuit.

In FIG. 1, reference symbol H indicates a head portion, and P indicates a pulse heat power source. The head unit H has a base 10, a driving unit 12 disposed above and facing the base 10, and a foot switch 14. The printed circuit board 16 is mounted on the base 10.
Is held. The driving section 12 has a movable section 20 which is moved up and down by an air cylinder 18. The movable section 20 holds a heater chip 22 located above the printed circuit board 16. The heater chip 22 descends integrally with the movable part 20 by the operator stepping on the foot switch 14 and supplying air to the air cylinder 18,
The printed board 16 is pressed with a predetermined pressure.

The heater chip 22 is made of molybdenum ( _MO ) or the like, and is formed in a substantially U-shape as viewed from the front as shown in FIG. The heater chip 22 is heated by a pulse-like heater current I supplied from a power supply P.
The work includes a circuit pattern 24 on the printed circuit board 16, a solder layer 26 supplied by pre-soldering the circuit pattern 24 or dipping the circuit pattern 24 in a molten solder layer, and an IC or the like superimposed on the solder layer 26. The lead 28 is formed.

The heater chip 22 is pressed against the work by the drive unit 12 and generates heat when a heater current is supplied. Due to the heat generated by the heater 22, the solder layer 26 is melted. Thereafter, the heater current is cut off to cool the solder, and the solder is solidified before the heater chip 22 is raised. During this time, the heater temperature T is detected by the thermocouple 30 adhered to the heater chip 22. Further, the pressing force P of the heater chip 22 against the work can be changed in, for example, two stages as described later.

Next, the pulse heat power supply P will be described with reference to FIGS. In FIG. 2, 32 is a transformer unit, and 34 is a control unit. The transformer section 32 includes a welding transformer 36, and a primary winding of the welding transformer 36 is supplied with a 200 V single-phase AC voltage whose phase is controlled by the SCR stack 38. A low-voltage alternating current induced in the secondary winding of the welding transformer 36 is supplied to the heater chip 22.

The phase of the AC power supplied to the primary side of the welding transformer 36 is detected by the insulating transformer 40 and input to the phase control circuit 42 in the control unit 34. The phase control circuit 42 synchronizes with a synchronization signal (SYNC) indicating a zero-crossing point at which the AC power supply voltage becomes zero, and
A gate signal G having the conduction angle θ (FIG. 3) set by the PU 70 is sent to the SCR drive circuit 44. The gate signal G is converted into a gate drive signal of a predetermined voltage level by the SCR drive circuit 44 and
The CR is alternately turned on and off.

The current on the secondary side of the welding transformer 36, that is, the heater current I is determined by a current detector 46 using a Hall element or the like.
Is amplified to a predetermined voltage level by an amplifier (AMP) 47, and the signal i is input to an integrator 48 in the control unit 34. This integrator 48 is, as shown in FIG.
It has an integrating capacitor 52 connected to the collector of the transistor 50, and a switching transistor 54 for discharging the electric charge of the integrating capacitor 52. The output of the current detector 46 is amplified and becomes a signal i, which is led to the base of the PNP transistor 50 and the capacitor 5
2 is changed.

The switching transistor 54 is turned on by the reset signal R (FIG. 3) obtained by the phase control circuit 42. At this time, the charge of the capacitor 52 is discharged through the transistor 54. As a result, the capacitor 52
Indicates the integral value of the heater current I shown in FIG. 3 every half cycle. This output is guided to a changeover switch (multiplexer) 56. Note the reset signal R is a signal output with a delay of a short time t _R with the sync signal SYNC, a slight delay in resetting the capacitor 52 to the zero-cross point of the AC power supply.

The output voltage of the thermocouple 30 is amplified by an amplifier 58 as compensation means and guided to a changeover switch 56. The changeover switch 56 selects a signal indicating the heater current I output from the integrator 48 and a signal indicating the heater temperature T with a time lag, and sends the digital signal to the CPU 70 by the A / D converter 60. . Here, the integrator 48
Is reset at twice the frequency of the AC power supply, the changeover switch 56 needs to sample the capacitor voltage at the same frequency as the reset signal R. For example selector switch 56 when the power supply frequency is 50H _Z is 100
At a sampling frequency of H _Z, 10 msec in other words
The heater current I is sampled every time.

On the other hand, since the output of the amplifier 58 indicating the heater temperature T is not subject to such regulation of the power supply frequency, the changeover switch 56 is set to, for example, 0.5 sec (500 msec, 2 msec).
It suffices to select every _HZ ). The heater chip 22
When the power supply time is sufficiently short, it is preferable to shorten the sampling period of the heater temperature T, for example, to 0.2 seconds so that the graphic display of the temperature described later can be seen smoothly.

The temporal changes of the heater temperature T and the heater current I detected in this way can be graphically displayed on the display device 62 of the pulse heat power source P shown in FIG. For example, a graphic can be displayed as shown in FIG. Here shows a case of performing the case, namely the one-stage heating is controlled to be constant by simply setting the temperature T _O of the heater temperature T. Therefore heater current I is greater during the heating immediately after the start of energization, then the heater current is sharply in order to prevent overshoot of the current I, also constant heater current I after reaching a predetermined temperature T _O.

The air pressure output from the air pump 64 is supplied to the cylinder 18 provided in the driving section 12 of the head section H after being adjusted by the pressure adjusting section 66. That is, the constant air pressure output from the air pump 64 is adjusted to one or a plurality of predetermined pressures by the pressure adjusting unit 66, and the air cylinder 18
Supplied to The pressure adjusting section 66 can be formed by, for example, one or a plurality of relief valves operated by an electromagnetic valve. This pressure adjusting unit 66 is a pressing force control unit 6 of the control unit 34.
8 is controlled.

[0032]

[Control Circuit] Next, a control circuit will be described with reference to FIGS. Reference numeral 70 denotes a CPU (microcomputer), to which the phase control circuit 42 , the A / D converter 60, and the pressing force control unit 68 are connected via a bus 72. The input device 78 and the display device 62 are connected to the bus 72 via I / O interfaces 74 and 76, respectively. The foot switch 14 is also connected to the bus 72 via an interface 80.

The input device 78 inputs numerical values, instructions, and the like from a switch group 78A provided on the front surface of the case of the pulse heat power supply P shown in FIG. The display device 62 displays the change in the heater temperature and the like as described above. The display device 62 may display an error when an abnormality occurs in the operation. This error display may be displayed using a separately provided LED (light emitting diode) or a warning buzzer may be sounded.

The bus 72 is also connected with a judgment means 82, a memory means 84, and the like. The judging means 82 has a function of judging whether or not the heater temperature T has reached the set lower limit temperature, and changing the pressing force when the temperature has reached.

The memory means 84 stores a temperature profile, that is, a control pattern for the time of the target heater temperature, and a lower limit temperature for changing the pressing force.
The pattern, temperature, and time of the temperature profile can be changed by the input device 78. The determination means 82 may cause the CPU 70 to have the function.

[0036]

[Outline of Operation] Next, the outline of the operation of this apparatus will be described with reference to the operation timing chart of FIG. In FIG. 7, P ₀ indicates a temperature profile. This temperature profile P ₀ indicates a target temperature during heating. The broken line in the figure indicates the actual heater temperature T. With heating in two stages in this embodiment, rise-up time t _up1, t _up2 is provided a time required in the temperature rise.

A first lower limit temperature T _L1 = T ₁₀ -a determined by subtracting a constant temperature from a first set temperature T ₁₀ (for example, 150 ° C.) in the first stage heating, and a second set temperature in the second stage heating. A second lower limit temperature T _L2 = T ₂₀ −b determined by subtracting a constant temperature from T ₂₀ (for example, 300 ° C.) is also set.
Here, a and b can be set to, for example, 20 ° C., and the lower limit temperatures T _L1 and T _L2 can be set to 130 ° C. and 280 ° C. These set values are also stored in the memory means 84.

When using this apparatus, first, a work is placed under the heater chip 22 as shown in FIG. 2, and the foot pedal 14 (FIGS. 1, 6) is depressed. Then, the heater current starts to flow. While monitoring the heater temperature T, the CPU 70 determines the phase angle θ of the heater current that minimizes the difference between the temperature profile P ₀ and the actual heater temperature T. The phase control circuit 42 controls the gate of the SCR so as to have the phase angle θ. Note that the actual heater temperature T is higher than the temperature profile P ₀ before the start of heating. This means that the temperature profile P ₀ is 0 ° C. before the start of heating, whereas
This is because the actual heater temperature T is relatively high due to the outside air temperature or the residual heat of the previous bonding process.

When the judging means 82 detects that the heater temperature T has risen and has reached the first lower limit temperature TL1, the CPU 82
70 sends a signal to the pressing force control means 68. Then, the pressing force control means 68 sends a signal to the pressure adjusting section 66 to cause the cylinder 18 to supply a predetermined air pressure. Therefore, the cylinder 18
Lowers the heater chip 22 to press the work with the first set pressure _pR1 .

The CPU70 also when the heater temperature T reaches the first lower limit temperature _{T L1,} the heating time of the first stage heating _{t h1}
Start counting. Then, the second stage heating is started after the lapse of the time _th1 . During the second stage heating, the heater temperature T
There the decision unit 82 that it has reached the second lower limit temperature T _L2 is detected, CPU 70 sends a signal to the pressing force control unit 68 so as to p _R2 reduces the pressing force of the heater chip 22. The pressing force controller 68 reduces the air pressure supplied to the cylinder 18 by the pressure adjusting unit 66 based on this signal, and sets the pressing force to _pR2 .

Further heater temperature T in CPU70 starts counting the second lower limit temperature _{T L2} from the time it reaches the heating time of the second stage heating _{t h2,} cut off the heater current I upon elapse of the time _{t h2} I do. The interruption of the heater current causes the heater temperature T to start decreasing. In the memory means 84,
A set temperature T _S lower than the solder solidification temperature at the time of the heater temperature drop is preset, and when the judging means 82 detects that the heater temperature T has dropped to this set temperature T _S , the CP
U70 sends a signal to the pressing force control unit 68 to raise the heater chip 22. That is, the heater chip 22 is separated from the work.

According to this embodiment, the heater chip 22
Is pressed against the work after rising to the first lower limit temperature TL1, so that the heating time of the work is shortened, and the work can be protected from thermal damage. Also, since the pressing force is increased during the first-stage heating, the heat of the heater chip 22 is smoothly transmitted to the work, so that the work can be heated quickly, and the pressing force is reduced near the solder melting temperature. It can be prevented from flowing out of the joined part. In addition, there is no possibility that the solder flowing out of the joints short-circuits the surrounding circuits.

[0043]

FIG. 8 is a timing chart showing another embodiment. In this embodiment, the rise-up times t _up1 and t _up2 in the temperature profile P ₀ of FIG. 7 are both set to zero. In this figure, the same parts as those in FIG. 7 described above are denoted by the same reference numerals, and the description thereof will not be repeated.
According to this embodiment, the same effect as the embodiment of FIG. 7 can be obtained.

[0044]

FIG. 9 is a timing chart showing another embodiment. The temperature profile P ₀ shown here is for one-stage heating, and is provided with a rise-up time t _up during heating.

In this embodiment, when the heater temperature rises,
Two lower limit temperatures T _La and T _Lb are set. These lower limit temperatures T _La and T _Lb can be set as, for example, temperatures obtained by subtracting constant temperatures a and b from the heating set temperature T ₀ . Heater temperature T is higher pressure p the pressure of when it reaches the first lower limit temperature _T La _{(<T Lb)} heater chip 22
_When the heater temperature T reaches the second lower limit temperature _TLb , the pressing force is reduced to _pR2 (< _pR1 ).

[0046] Then shut off the heater current with the lapse of heating time t _h, increases the heater chip 22 when the heater temperature T decreases to the set temperature T _S. According to this embodiment, substantially the same effects as in the embodiment of FIGS.

[0047]

FIG. 10 is a timing chart showing another embodiment. The temperature profile P ₀ shown here is one-step heating in a step-like manner, and the rise-up time t _up during heating is made zero.

In this embodiment, the lower limit temperature T _L = T ₀ -a which is lower than the heating set temperature T ₀ by a certain temperature is set. In FIG. 10A, when the heater temperature T reaches the lower limit temperature _TL , the heater chip 22 is pressed against the work by the pressing force p _R.
In pressed, it raises the heater chip 22 becomes the set temperature T _S during cooling after shut-off the heater current is intended to separate from the workpiece. Therefore, the contact time between the heater chip 22 and the work is shortened, and the work can be protected from thermal damage.

FIG. 10B shows a foot switch 1.
4 (FIGS. 1 and 6) is detected, the heater chip 22 is lowered, and pressing is started with the pressing force _pR1 . When the heater temperature T reaches the lower limit temperature _TL , the pressing force is reduced to _pR2. (<P _R1 ). Therefore, it is possible to prevent the molten solder from flowing out from the portion to be joined to the surroundings, and it is less likely that the molten solder flowing out around the circuit will short-circuit the circuit.

[0050]

[Effect of the Invention] As described above the present invention of claim 1, before the heater temperature reaches the lower limit temperature which is set lower than the bonding temperature
The heater starts to be pressed against the part to be joined at
Since those continue to push to decrease the pressing force of the heater chip when elevated to reach arrives at the lower limit temperature, the molten solder
Can be prevented from flowing out of the joint
Short circuit of the surrounding circuit can be prevented.

[0051] In this case, the heater temperature is the lower limit temperature
If the heater is brought into contact with the part to be joined and the pressing is started from when the temperature reaches another lower limit temperature , the heating time of the part to be joined is shortened, and the possibility that the part to be joined is thermally damaged is reduced.
(Claim 2).

When the temperature profile is two-stage heating, a first lower limit temperature lower than the first set temperature of the first stage heating and a lower temperature higher than the first set temperature and lower than the second set temperature of the second stage heating. A second lower limit temperature is set, pressing of the heater is started at the first lower limit temperature, and the pressing force is reduced at the second lower limit temperature.
Control can be performed so as to continue pressing . In this case, it is possible to prevent the occurrence of thermal failure of the work and the outflow of the molten solder.

The temperature profile rises almost linearly from the start of heater heating to a set temperature higher than the bonding temperature.
Step heating can be adopted (claim 4 ). In the case of this one-stage heating, the first and second lower limit temperatures are set during the substantially linear heating, and the heater is brought into contact with the work at the first lower limit temperature.
By reducing the pressure in the second lower limit temperature, thereby preventing thermal failure of the workpiece and the prevention molten solder flows out (claim 5).

According to the sixth aspect of the present invention, there is provided a bonding apparatus directly used for performing the above method. Here the judgment means
Indicates that the heater temperature has reached another lower temperature
If the pressing force control means starts pressing the heater based on the other determination signal, the heating time of the work is shortened, and the work is heated. Molten solder will flow around.
It can be prevented from being issued (claim 7 ). Claims
According to the apparatus of No. 8 , it can be applied to the processing based on the temperature profile of the two-stage heating, and the same effect is obtained.

[Brief description of the drawings]

FIG. 1 is an external view of a bonding apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a pulse heat power supply.

FIG. 3 is a diagram showing a heater current waveform and the like.

FIG. 4 is a diagram showing a heater current detection circuit;

FIG. 5 illustrates a display example of a display device.

FIG. 6 is a functional block diagram of a control circuit.

FIG. 7 is a control timing chart.

FIG. 8 is a control timing chart showing another embodiment.

FIG. 9 is a control timing chart showing another embodiment.

FIG. 10 is a control timing chart showing another embodiment.

[Explanation of symbols]

Reference Signs List 18 air cylinder 22 heater chip 30 thermocouple as heater temperature detecting means 32 transformer section 34 control section 36 welding transformer 66 pressure adjusting section 68 pressing force control section 70 CPU 82 determination section 84 memory section P0 temperature profile T _L1 , T _La 1 lower limit temperature _TL2 , _TLb second lower limit temperature

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05K 3/34 507 B23K 3/04 H05K 3/32

Claims (8)

(57) [Claims] 1. A while heating the bonding portion is pressed by the heater, by feeding back the heater temperature to follow the temperature profile was set heater temperature in advance, the joint
A control method for use in a pulse heating type joining apparatus in which a heater is separated from a portion to be joined after heating and cooling, wherein the heater temperature is set by the temperature profile.
Before reaching the lower limit temperature set lower than the joining temperature of the joint
Then, the heater starts to be pressed against the portion to be joined, and then the heater
The temperature of the heater is increased to reach the lower limit temperature, and the pressing force of the heater against the joined portion is reduced.
The method of pulse heat type bonding apparatus according to claim Rukoto continue to press. 2. The method according to claim 1, wherein the heater temperature is lower than the lower limit temperature .
2. The method according to claim 1, wherein the pressing is started by bringing the heater into contact with the portion to be joined after reaching the lower limit temperature . 3. The temperature profile includes a first stage heating for heating to a first set temperature lower than a joining temperature of the portion to be joined and a second stage heating for heating to a second set temperature higher than the first set temperature. While heating in stages, it is detected that the heater temperature has reached the first lower limit temperature lower than the first set temperature, the heater is brought into contact with the portion to be joined, and pressing is started.
Control of pulse heat type joining apparatus according to claim 1 that continue to press to reduce the pressing force of the heater by detecting the arrival to the higher than first set temperature and lower than said second predetermined temperature the second lower limit temperature Method. Wherein said temperature profile is Pas <br/> Rusuhito type joining apparatus according to claim 1 or 2 to raise the heater temperature substantially linearly from the start of heating of the heater to a higher setting temperature than the bonding temperature of the bonding portion Control method. 5. The method according to claim 1, further comprising the steps of:
A lower limit temperature is set, it is detected that the heater temperature has reached the first lower limit temperature, the heater is brought into contact with the portion to be joined, pressing is started, and it is detected that the heater temperature has reached the second lower limit temperature. The method according to claim 4 , wherein the pressing force of the heater is reduced to continue pressing . 6. A while heating the bonding portion is pressed by the heater, by feeding back the heater temperature to follow the temperature profile was set heater temperature in advance, after heating and cooling
In pulse heat type joining apparatus for joining by releasing from the junction a heater, and the heater temperature detection means for detecting the heater temperature, the temperature profile and the temperature profile
Memory means for storing a lower limit temperature set lower than the joining temperature of the portion to be joined set, and determination means for detecting that the heater temperature has reached the lower limit temperature during the rise, and outputting a determination signal , Pressure adjusting means for changing the pressing force of the heater against the joined portion; and the heater before the judging means outputs a judgment signal.
Start the pressing of the bonded portion and reduce the pressing force of the heater on the bonded portion based on the determination signal.
And a pressing force control means for continuously pressing and pressing . 7. The determining means determines that the heater temperature is lower than the lower limit temperature.
Other lower limit temperature is detected and other judgment signals
Is output, and the pressing force control means outputs the
7. The pulse heating type bonding apparatus according to claim 6 , wherein the heater is brought into contact with the portion to be bonded to start pressing. 8. The pressure adjusting means can change the pressing force of the heater in at least two stages, and the memory means stores first and second lower limit temperatures on a low temperature side and a high temperature side,
Claim the pressing force control means that keeps pressed to reduce the pressing force reaches the second lower limit temperature and starts pressing by contacting a heater onto the junction when the heater temperature reaches the first lower limit temperature 7. A pulse heating type bonding apparatus.