JP6662553B2 - Thermal welding equipment - Google Patents

Description

The present invention relates to a heat welding method for supplying an optimal voltage and current for performing heat welding and a heat welding apparatus therefor.

With the recent energy savings, the use of LEDs for electric lights and automotive lights has been promoted, and the demand for incorporating a large number of LEDs into electric lighting devices and automotive light housings has been increasing.

For this reason, a thermal welding method and its device capable of simultaneously performing dozens of thermal caulking are required. As this device, those disclosed in JP-A-2004-090558 and JP-A-2008-114518 are disclosed. Are known.

JP-A-2004-090558 JP 2008-114518 A

The heat welding apparatuses disclosed in Patent Documents 1 and 2 control an AC power supply with a power regulator such as an SSR, and apply a low-voltage large current to a heat-welding chip in which an AC current stepped down by a transformer is connected by an electric wire. Fever.

However, in order to perform thermal caulking at multiple points, as many transformers as the number of heat welding chips are required, so that the size of the heat welding device is increased and the weight of the transformer is also a serious problem.

Further, the transformer needs a capacity suitable for the resistance value (heat generation amount) of the heat welding chip, and when the size of the heat welding chip is changed, it is necessary to replace the transformer according to the resistance value.

It is an object of the present invention to provide a method and apparatus for performing heat welding that is excellent in miniaturization, weight reduction, cost reduction, and energy saving of an apparatus body to be implemented.

In order to achieve the above object, an invention according to claim 1 is an impulse heating type heat welding apparatus for applying a DC current to a resistance heating element, wherein the DC / DC converter reduces a DC power supply applied to the heating element. And a heat welding power supply circuit integrally provided with a control circuit for down-converting the voltage to 1/6 to 1/40 and increasing and converting the current to 6 to 40 times via the DC / DC converter. And a power supply circuit for applying a DC current output from the welding power supply circuit to the resistance heating element, comprising two or more heat welding power supply output circuits, each of which has an independent output voltage. And the output current can be changed, and the heat welding power supply circuit is arranged in a welding jig .

According to the first aspect of the present invention, in a heat welding apparatus of an impulse heating system for applying a DC current to a resistance heating element, a DC / DC converter for reducing a DC power supply to 1/6 to 1/40, and the DC / DC converter A heat welding power supply circuit integrating a control circuit for controlling the DC / DC converter is provided, and a current whose DC current is increased by 6 to 40 times is applied to the heat welding power supply circuit to generate heat. This eliminates the need for an SSR (power regulator) for controlling the AC power supply and a transformer for stepping down the AC voltage, which were indispensable in the conventional heat welding method and its apparatus. it can.

In addition, stable heat welding can be performed even if the factory voltage fluctuates, and the circuit and device can be downsized, and the weight can be reduced significantly and the cost can be reduced by eliminating the transformer.

Further, it is possible to individually optimize variations in heat generation in simultaneous machining of a plurality of points by adjusting output voltage and output current.

Further, the power supply portion can be mounted on the jig unit and the power supply wiring to the heat welding chip is shortened, so that the power loss is reduced, for example, from 5 m to 0.5 m, 121.6 W to 12.1 W. be able to.

In addition, the AC high voltage input is up to the stabilized power supply, and all the wiring thereafter is at a low voltage of 12 V DC or less, which is excellent in safety.

In addition, a portable calorie deposition device that can be welded by a battery power supply even in a place where there is no AC power supply can be realized.

In addition, the change of the welding tip (power consumption) can be dealt with only by changing the condition within the rated range of DC / DC switching or transformer replacement.

The schematic diagram which shows the structure of a heat welding apparatus. The figure which shows the structure of a heat welding power supply. FIG. 2 is a schematic diagram illustrating a configuration of a heat welding apparatus according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of a heat welding power supply according to the first embodiment. FIG. 4 is a schematic diagram illustrating a schematic configuration of a heat welding apparatus according to a second embodiment. Schematic diagram showing the configuration of a conventional heat welding device Power loss comparison graph of robot cable Weight comparison graph of heat welding power supply

Hereinafter, a heat welding apparatus 1 of the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 shows a schematic configuration of the heat welding apparatus 1.

The heat welding apparatus 1 includes a PLC 9, an operation panel 15, a stabilized DC power supply 2, a heat welding power supply 3, a robot cable 8, a heat welding chip 7, and a receiving jig 14.

In addition, a normal heat welding device is a control device and a position sensor for controlling the operation of the air or servo cylinder or the above-mentioned cylinder for moving the heat welding chip forward and backward with respect to the work to be welded, and a cooling device for the heat welding chip. And the like, but the description of the structure and operation is omitted.

The heat welding power supply 3 is driven by DC 12V supplied from a DC stabilized power supply 2 for converting AC 100V (or 200V) of a factory power supply into DC 12V.

In general, the power supply voltage of a factory may fluctuate depending on the installation location of the machinery and equipment, the surrounding machine operation status, day and night, and such voltage fluctuation may cause unstable operation of the connected machinery. is there. This problem is more likely to occur in regions where power conditions are more unstable overseas than in Japan.

The stabilized DC power supply 2 is a switching type step-down rectifier circuit, and has a wide adaptable voltage input voltage range of 80 to 240 VAC. Therefore, even if the factory power supply fluctuates, the voltage of the converted and output 12 V DC power supply is kept constant, the stable operation of the heat welding power supply 3 becomes possible, and the power supply to the heat welding chip 7 is stabilized.

The overseas single-phase AC power supply is 100 V to 240 V, but it is needless to say that the stabilized DC power supply 2 can be used in any region.

Further, the output of the stabilized DC power supply 2 is not limited to 12 V, but can be appropriately selected according to the input / output voltage current of the DC / DC converter 5.

By operating the operation panel 15, a servo cylinder (not shown) connected to the PLC 9 is operated to move the heat welding chip 7 toward and away from the work, and at the same time, control the operation of the heat welding power supply 3.

The PLC 9 monitors the heating temperature of the heat welding chip 7 using a thermocouple (not shown) and performs heating temperature feedback control. At the same time, the PLC 9 determines the voltage, current, and energizing time of the DC power supplied from the heat welding power supply 3 to the heat welding chip 7. The heating of the heat welding tip 7 is controlled according to the temperature profile set by the control.

In the case of the conventional AC heat welding apparatus using the transformer shown in FIG. 6, the capacity of the transformer 11 is selected according to the resistance value of the heat welding chip 7, so that the heat welding chip 7 has a different resistance value (heat generation amount). ), It was necessary to switch the tap of the transformer 11 or replace the transformer 11.

However, the heat welding power supply 3 according to the present invention can change the output voltage of the DC / DC converter 2 according to the instruction of the PLC 9, and it is easy to replace the heat welding chip 7 with one having a different resistance value.

FIG. 2 shows the configuration of the heat welding power supply 3.

The heat welding power supply 3 includes a control circuit 4 and a DC input / output board 6 on which a DC / DC converter 5 is mounted to perform power conversion.

The DC input / output board 6 is a mounting section for mounting the standardized DC / DC converter 5. Further, the DC / DC converter 5 has a noise removing circuit on the input / output side and the output side.

The DC / DC converter 5 in this embodiment is a digitally controlled DC / DC module 100A manufactured by TDK, and has a specification of 8 to 14V input DC and 0.6 to 2.0V output DC. The operating conditions are 12V input DC, 1.0V DC output, 80A output current. is there.

The control circuit 4 that has received the control signal from the PLC 9 controls the power conversion operation of the DC / DC converter 5, and the DC / DC converter 5 converts DC12V from the DC stabilized power supply 2 to DC1.0V according to a command from the control circuit 4. Step down and output a maximum of 100A.

At this time, since the input voltage 12V is stepped down to 1/12 of 1V and output, the current can theoretically be increased 12 times, but the DC / DC converter 5 has a variable efficiency of 85-85. Since it is 90%, the actual current can be increased up to about 10 times.

Since the current is 100 A at the maximum when the output voltage to the thermal welding chip 7 is 1.0 V, the required input current is about 10 A at 1/10 of the output 100 A from the above calculation.

The power of the CD12V 10A supplied to the DC / DC converter 5 can be easily supplied by using a commercially available DC stabilized power supply (AC / DC converter), leading to cost reduction.

The input and output voltages and currents in the present embodiment are examples, and the input and output values of the heat welding power supply 7 are within the range of the performance of the DC / DC converter 2, and the resistance value of the heat welding chip 7 and the required heating temperature It is needless to say that the user can select freely.

Further, since the control circuit 4 has a function of measuring and monitoring the voltage, current, and temperature of the heat welding tip and a function of communicating with the PLC, it is possible to set processing conditions, perform measurement during processing, and perform feedback management of measurement monitoring information from the PLC. . Therefore, there is no need to separately install a measuring device, and the device can be reduced in size and simplified.

In this embodiment, a thermal welding apparatus 1 having four thermal welding tips 7 is shown in FIG.

The heat welding apparatus 1 includes a PLC 9, an operation panel 15, a stabilized DC power supply 2, a heat welding power supply 3, a robot cable 8, a heat welding chip 7, and a receiving jig 14.

Since the number of the heat welding chips 7 is four, the input current required for the heat welding power supply 3 is 10 A × 4 = 40 A as described above, but the DC stabilized power supply 2 used an output of 12 V and 50 A with a margin.

As a comparative example, FIG. 6 shows a heat welding apparatus 1 using a conventional SSR 10 and a transformer 11. The SSR and the transformer need to be installed adjacent to each other, and the heavy transformer must be mounted on the lower side of the main body of the heat welding apparatus 1. For this reason, since the long robot cable 8 is connected to the heat welding chip 7, power loss due to the internal resistance of the robot cable 8 is inevitable.

Further, FIG. 3 shows a heat welding power supply 3 corresponding to the four-point heat welding chip of this embodiment.

The heat welding power supply 3 of this embodiment has a control circuit 4 and four DC input / output boards 6 mounted in one unit. The external dimensions of the unit are as small as 194 mm × 176 mm × 42 mm, and the weight including the case is 1 kg. .

Since the heat welding power supply 3 is small and lightweight in this manner, the heat welding power supply 3 can be installed at a position close to the heat welding chip 7, and a robot cable 8 for supplying power from the welding power supply 3 to the heat welding chip 7. Can be minimized to reduce power loss.

FIG. 7 shows a comparative example of the power loss.

Robot cable thickness 5.5 sq Resistance 3.8 mΩ / m In the case of a current of 80 A, the power loss P is reduced to 1/10 by reducing the length of the robot cable 8 to 1/10.

Power Loss P Comparison Formula P = I × I × R
Resistance of conventional 5 m robot cable = 3.8 mΩ × 5 m = 0.19Ω
P = 80 × 80 × 0.019 = 121.6W
The power loss was 121.6 W × 4 = 486.4 W.

This embodiment
0.5m robot cable resistance = 3.8mΩ x 0.5m = 0.0019Ω
P = 80 × 80 × 0.0019 = 12.16W
12.16W × 4 = 48.6W

486.4W (conventional) -48.6W (this embodiment) = 437.8W
437.8W power loss reduction

Next, FIG. 7 shows a comparison between the weight of the welding power source and that of the conventional heat welding apparatus 1.

Conventional weight comparison
SSR 0.5kg + transformer 4kg = 4.5kg
4.5 kg x 4 points = 18 kg
When 3 kg of transformer mounting base is added, the total is 21 kg.

This embodiment
DC stabilized power supply 2 (50A) 1.6kg
Thermal welding power supply 3 (for 4 points) 1.0kg Total 2.6kg

Light weight 21kg-2.6kg = 18.4kg

Since the welding point reaches 40 points in the actual heat welding device of a vehicle lighting device, the weight difference of the entire heat welding power source is close to 100 kg, and the size and the manufacturing cost of the heat welding device 1 are greatly different.

Further, when a plurality of heat welding chips 7 are used, the heat generation temperature (resistance value) may vary depending on individual differences of the heat welding chips 7, but the heat welding power supply 3 corresponds to four heat welding chips 7. Since the four DC input / output boards 6 are mounted, it is possible to individually increase or decrease (correct) the voltage and current applied by the command of the PLC 9.

For this reason, it is possible to suppress the variation in the heating temperature of the plurality of heat welding chips 7 and stabilize the quality of the heat welding in a certain processing time.

FIG. 5 shows an embodiment of the heat welding apparatus 1 using a battery 13 as a DC power supply.

In this embodiment, the battery 13 is a power supply, and the output from the heat welding device 1 in which the PLC 9, the control circuit 4, the DC / DC converter 5, and the DC input / output board 6 are integrated is connected to the heat welding chip 7. 2 except that the power supply is different.

The heat welding device 1 is provided with a connection terminal for inputting a processing program to the PLC 9 and a start switch for starting the heat welding process, but they are not shown.

In this embodiment, the operation panel connected to the PLC 9 is omitted in order to reduce the size of the heat welding apparatus 1. For this reason, the processing conditions are set by connecting a personal computer to the connection terminal.

Since the input voltage of the DC / DC converter 5 corresponds to 8 to 24 V, the type of the battery is not particularly limited. It is possible to select them appropriately and use them in combination.

Here, assuming that the welding current of the heat welding tip 7 is 80 A, the voltage is 1.0 V, and the welding time is 2 seconds, the power consumption at one time is 0.044 Wh.

The number of times that welding can be performed in the case of 18650 size, which is widely distributed as a small lithium-ion battery, and has a capacity of 3000 mA in series with three power supplies,
Battery capacity 3.7V x 3Ah x 3 = 33.3Wh
Number of times that welding is possible 33.3Wh ÷ 0.044Wh ≒ 750 times

At the time of operation, the number of machining decreases due to the power consumption of the PLC 9, the conversion loss of the DC / DC converter 5, and the conduction loss in the electric wire, and the number of stable machining changes due to the discharge characteristics of the battery. It can be processed about once.

Conventional heat welding can be performed only in a place where an AC power supply can be secured. However, according to the present embodiment, a hand-held, cordless heat welding apparatus can be used, and it is difficult to secure an AC power supply outdoors or inside a building. In addition, heat welding can be performed in a narrow place such as in a mechanical device.

Furthermore, when using a 12V80Ah lead battery for automobiles,
Battery capacity 12V × 80Ah = 9600Wh
9600Wh ÷ 0.044Wh ≒ 200,000 times or more

Assuming that the number of times of processing per day is 1000 times, heat welding can be performed for several days even in consideration of the power loss and the discharge characteristics of the battery described above. Operation is also possible.

1. Heat welding equipment 2. DC stabilized power supply (AC / DC converter)
3 Heat welding power supply 4 Control circuit 5 DC / DC converter 6 DC input / output board 7 Heat welding chip 8 Robot cable (power supply cable)
9 PLC (Programmable Logic Controller)
10 SSR (Solid State Relay)
11 Transformer 12 AC power supply 13 Battery (secondary battery)
14 Receiving jig 15 Operation panel

Claims (1)

In a heat welding apparatus of an impulse heating system for applying a DC current to a resistance heating element, a DC / DC converter for decreasing a DC power applied to the heating element, and a voltage of 1/6 to 1 via the DC / DC converter. A heat welding power supply circuit integrally provided with a control circuit for down-converting the current to / 40 and increasing the current by a factor of 6 to 40, and applying a DC current output from the heat welding power supply circuit to the resistance heating element Power welding circuit, comprising two or more heat welding power supply output circuits, each heat welding power supply output circuit can independently change the output voltage and output current, the heat welding power supply circuit to the welding jig An impulse heating type heat welding apparatus, which is disposed.

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