Welding inverter with your own hands. Ultra-budget dot welding of lithium batteries at home Spot welding control unit on Arduino microcontroller

In the life of each "radio engineer", the moment occurs when you need to cook with each other lithium batteries - either when repairing a laptop battery die from age, or when assembling nutrition for the next craft. To solder a "lithium" 60-watt soldering iron and is terrible - a little overload - and you have a smoke grenade in your hands, which is useless to extinguish water.

Collective experience offers two options - either go to the garbage in search of an old microwave, get it up and getting a transformer or pretty to spend.

I absolutely did not want to seek a transformer in a year for a year, cut it and rewind. I wanted to find an ultra-owned and ultrafreight way to weld batteries electric shock.

Powerful low-voltage source direct currentAvailable to everyone is the usual B. Akb from the car. I am ready to argue that he already has somewhere in the storage room or will be found at the neighbor.

Suggest - the best way Get the old Akb task - it

wait for frosts. Go to the poorhage, who does not start the car - he will soon run for a new fresh battery to the store, and the old give you just like that. In the cold, the old lead acb can and does not work well, but after the charge of the house in warmth will be released on a complete container.

To weld batteries with current from the battery, we will need to give out the current with short pulses in a few milliseconds - otherwise we will not get welding, but burning holes in the metal. The cheapest and affordable way to switch the current 12-volt battery is an electromechanical relay (solenoid).

The problem is that the usual automotive relays by 12 volts are calculated by a maximum of 100 amps, and short circuit currents during welding are many times more. There is a risk that an anchor relays is simply welded. And then on the expanses Aliexpress I came across the motorcycle starter relay. It was thought that if these relays are withstanding the starter current, and many thousand times, then for my purposes it will be good. Finally convinced this video, where the author is experiencing a similar relay:

Came acquaintance, brought two latries-a and asked, and is it possible to make SPOTTER? Usually, having heard a similar question, an anecdote comes to the mind about how one neighbor is interested in another, whether he knows how to play the violin and hears "I don't know, I didn't try" - so I have the same answer - I do not know , Probably "yes", and what is "spotter"?

In general, tea was boiled and brewed, he heard a small lecture that it is not necessary to do what it is not necessary to do that it is necessary to be closer to the people and then people will reach me, and also briefly plunged into the history of car repair shops illustrated by savory Bikes from the life of "Kostopravov" and "Tinsmiths". After that, I realized that Spotter is such a small "welder", working on the principle of point welding apparatus. Used for "clipping" metal Syb. and other small fasteners To a distorted car body, with which the deformed tin is then straightened. True, there is still " reverse hammer"Needed, but they say that this is not my concern - only the electronic part of the scheme is required.

Looking in the Scheme Schemes in the network, it became clear that a simibrator was needed, which would "open" simistor for a short time and feed the power voltage on the power transformer. The secondary winding of the transformer should produce a voltage of 5-7 V with a current sufficient for "sticking" the washers.

To form a simistor control pulse used different methods - From a simple condenser discharge before using microcontrollers with synchronization to network voltage phases. We are interested in that scheme, which is simpler - let it be "with a condenser".

Searches "in bedside table" showed that not counting passive elements, there are suitable simistors and thyristors, as well as many other "small things" - transistors and relays on different operating stresses ( fig.1). It is a pity that the optocouples are not, but you can try to assemble the capacitor discharge transmitter in a short "rectangle", which includes a relay that will open and close the simistor to its closing contact.

Also during the search for details there were several power supplies with output constant voltages from 5 to 15 V - chose an industrial from Soviet times called BP-A1 9B / 0,2A ( fig.2). With a load in the form of a resistor 100 Ohm, the power supply produces a voltage of about 12 V (it turned out that already converted).

Select from the existing electronic "garbage" Simistors TC132-40-10, a 12-ti-tolly relay, take several CT315 transistors, resistors, capacitors and begin to miss and check the diagram (on fig. 3. One of the settings).

What happened as a result is shown on figure 4.. Everything is quite simple - when you press the S1 button, the C1 capacitor begins to charge and a positive voltage is appear on its right output, equal to the power voltage. This voltage, passing through a current-rebuilding resistor R2, comes to the VT1 transistor database, it opens and voltage comes to winding the relay, and as a result, the contacts of the relay K1.1 are closed, opening the Simistor T1.

As the C1 capacitor charge, the voltage on its right output is smoothly reduced and when the level is less than the voltage of the transistor opening, the transistor closes, the relay winding will be de-energized, the open contact K1.1 will stop supplying the voltage to the control electrode of the simistor and it will close at the end of the current half-wave . VD1 and VD2 diodes are standing to limit emerging pulses when the S1 button is released and when de-energizing the winding of the relay K1.

In principle, everything works and it works, but when controlling the time of the open state of the Simistor, it turned out that it walked quite strongly. It would seem, even taking into account the possible changes of all delays in turning on-shutdown in electronic and mechanical circuits, it should be no more than 20 ms, but in fact it turned out more and plus to this, then the impulse lasts 20-40 ms longer, and That and all 100 ms.

After small experiments, it turned out that this change in the pulse width is mainly due to the change in the voltage level of the circuit and the operation of the transistor VT1. The first "cured" by installing mounted mounting inside the power supply unit of the simplest parametric stabilizer consisting of a resistor, stabitron and power transistor ( fig.5). And the cascade on the VT1 transistor was replaced by the Schmitt trigger on 2 transistors and the installation of an additional emitter repeater. The scheme took the view shown on Figure 6..

The principle of operation remained the same, added the possibility of a discrete change in the pulse duration with switches S3 and S4. Schmitt trigger is assembled on VT1 and VT2, its "threshold" can be changed in small limits by changing resistors R11 or R12 resistors.

When macating and checking the work of the electronic part of the spotter, several diagrams were removed, for which time intervals can be estimated and the front delays arising. In the diagram at this time there was a time-sensitive capacitor with a capacity of 1 ICF and resistors R7 and R8 had 120 com and 180 com, respectively. On the figure 7. The status on the winding of the relay is shown at the bottom - the voltage on the contacts when switching the resistor connected to +14.5 V (the file for viewing the program is in the archive application to the text, the voltage was removed through resistor dividers with random division coefficients, so the Volts scale It does not correspond to reality). The duration of all power pulses relays accounted for approximately 253 ... 254 ms, the switching time of contacts - 267 ... 268 ms. "Expansion" is associated with increasing trip times - this can be seen by figures 8. and 9 when comparing the difference arising from the closure and opening of contacts (5.3 ms against 20 ms).

To test the temporal stability of pulses formation, four consecutive inclusions with voltage control were carried out in the load (file in the same application). On generalized figure 10. It can be seen that all impulses in the load are sufficiently close in duration - about 275 ... 283 ms and depend on what place the half-wave of the network voltage came the moment of inclusion. Those. Maximum theoretical instability does not exceed the time of one half-wave of the network voltage - 10 ms.

When installing R7 \u003d 1 kΩ and R8 \u003d 10 kΩ at C1 \u003d 1, the ICF was able to obtain the duration of one pulse of less than one half-sender network voltage. At 2 μF - from 1 to 2 periods, at 8 μF - from 3 to 4 (file in the application).

In the final version of Spotter, parts were installed with the nominal numbers specified on figure 6.. What happened on the secondary winding power transformer, shown on figure 11.. The duration of the shortest pulse (first in the figure) is about 50 ... 60 ms, the second - 140 ... 150 ms, the third - 300 ... 310 ms, the fourth - 390 ... 400 ms (with the capacity of the current capacitor in 4 μF, 8 μF, 12 μF and 16 μF).

After checking the electronics, it's time to do "iron".

As a power transformer, a 9-tiamper latre was used (right on fig. 12). Its winding is made with a wire with a diameter of about 1.5 mm ( fig.13.) and the magnetic pipe has inner diametersufficient for winding 7-mi turns of 3 parallel aluminum tires common cross section About 75-80 sq. Mm.

The disassembly of LATER-A is carried out carefully, just in case, the entire constructive "fix" in the photo and "sink" conclusions ( fig.14.). It is good that the wire is thick - it is convenient to count the turns.

After disassembly, carefully inspect the winding, clean it from dust, garbage and graphite residues using painting brush With a rigid pile and wipe the soft cloth, slightly moistened with alcohol.

We fall to the output "A" five-chamber glass fuse, connect the tester to the "median" output of the coil "G" and supply voltage 230 V to the fuse and the output "Unnamed". The tester shows the voltage of about 110 V. nothing bithes and does not heat - we can assume that the transformer is normal.

Then the primary winding is winding up with fluoroplastic ribbon with such a falsestone so that at least two-three layers was obtained ( fig.15). After that, we wind the trial secondary winding of several turns flexible wire in isolation. Digging the power and measuring on this winding, we determine the desired number of turns to obtain 6 ... 7 V. In our case, it turned out that when 230 V to the conclusions "E" and "Unnamed" 7 at the outlet is obtained at 7 turns. When applying for "A" and "Unnamed", we get 6.3 V.

For the secondary winding, aluminum tires "Well, very used" were used - they were removed from the old welding transformer and the places were not insulated at all. In order for the turns not to be closed with each other, the tires had to wind sickle with ribbon ( fig.16.). The winding was carried out so that it turned out two or three layers of coating.

After winding the transformer and checking the performance of the scheme on the desktop, all parts of the spotter were installed in the body suitable in size (it seems that, too, from some LATER-A - fig.17).

The conclusions of the secondary winding of the transformer are clamped with bolts and M6-M8 nuts and are removed on the front panel of the case. These bolts on the other side of the front panel are attached power wiresgoing to the car body and the "reverse hammer". Appearance at the stage home check Shown on figure 18.. At the top of the left are the La1 network voltage indicator and the S1 power switch, and the right is the S5 pulse voltage switch. It commutes the connection to the network or the output "A" or the output of the transformer.

Fig.18.

Below are the connector for the S2 button and the outlook outputs. Pulse duration switches are installed at the bottom of the housing, under the folding lid (Fig.19).

All other scheme elements are fixed on the bottom of the case and front panel ( fig.20, fig.21, fig.22). It looks not very neat, but here the main task There was a decrease in the length of the conductors in order to reduce the effect of electromagnetic pulses on the electronic part of the circuit.

The printed fee was not divorced - all transistors and their "strapping" soldered to male Plate from fiberglass, with a foil chopped into squares (visible on fig.22).

Power switch S1 - JS608A, allowing switching of 10 A currents ("paired" pins of fasteners). The second such switch was not found and the S5 was set by TP1-2, its conclusions are also relentless (if you use it when the network power is turned off, it can pass through itself quite large currents). Switches of pulse duration S3 and S4 - TP1-2.

S2 button - km1-1. Connector for connecting the wires of the button - COM (DB-9).

Indicator LA1 - TN-0.2 in the appropriate installation fittings.

On the figures 23., 24 , 25 Photographs made when checking the performance of the spotter - furniture corner with dimensions of 20x20x2 mm dot pointed to a tin plate with a thickness of 0.8 mm (fastening panel from a computer case). Different sizes "Pigachkov" on fig.23 and fig.24 - This is with different "cooking" stresses (6 V and 7 V). Furniture corner in both cases is welded hard.

On the fig.26 Shown back side Plates and it can be seen that it warms up, paint burns and departs.

After he gave the spotter to a friend, he called about a week later, said that the reverse "hammer" did, connected and checked the work of the entire device - everything is fine, everything works. It turned out that the pulses of a large duration in the work are not needed (i.e., the elements S4, C3, C4, R4 can not be set), but there is a need to connect the transformer to the network "directly". As far as I understood, it is in order for using coal electrodes to warm the surface of the rummy metal. Make the supply of the power "directly" is easy - put a switch that allows you to slow down "power" conclusions of the simistor. A little embarrassing is not enough. A large total section lived in the secondary winding (it is necessary more than two weeks), but more than two weeks have passed, and the owner of the apparatus is warned about the "winding weakness" and does not call, it means that nothing terrible happened.

During experiments, the scheme was tested by a variant of the simistor collected from two thyristors T122-20-5-4 (they can be seen figure 1. on the background). The inclusion scheme is shown on fig.27 , VD3 and VD4 diodes - 1N4007.

Literature:

1. Gorakhkov B.I., "Radio electronic devices", Moscow, Radio and Communication, 1984.
2. Mass Radobibili, Ya.S. Kublanovsky, "Thyristor devices", M., "Radio and Communication", 1987, Issue.1104.

Andrei Goltsov, Iskitim.

List of radio elements

Designation	A type	Nominal	number	Note	Score	My notebook
	Figure No. 6.
VT1, VT2, VT3	Bipolar transistor	Kt315b	3			In notebook
T1.	Thyristor & Simistor	TC132-40-12.	1			In notebook
VD1, VD2.	Diode	KD521B.	2			In notebook
R1	Resistor	1 com	1	0.5 W.		In notebook
R2.	Resistor	330 com	1	0.5 W.		In notebook
R3, R4.	Resistor	15 com	2	0.5 W.		In notebook
R5	Resistor	300 Ohm.	1	2 W.		In notebook
R6.	Resistor	39 Ohm.	1	2 W.		In notebook
R7	Resistor	12 com	1	0.5 W.		In notebook
R8.	Resistor	18 com	1	0.5 W.

In some cases, instead of soldering it is more profitable to use spot welding. For example, this method can be useful for repair. rechargeable batteriesconsisting of several batteries. The soldering causes excessive heating of the cells, which can lead to their failure. But the point welding heats the elements is not as much as it acts relatively short time.

ARDUINO NANO is used to optimize the entire process in the system. This is a control unit that allows you to effectively manage the power supply of the installation. Thus, each welding is optimal for a particular case, and energy is consumed as much as necessary, not more, and no less. Contact elements here is copper wireand energy comes from a conventional car battery, or two if the current is required.

The current project is almost ideal from the point of view of the complexity of creating / efficiency. The author of the project showed the main steps of creating a system by posting all the data on the Instructables.

According to the author, the standard battery is enough for point welding of two nickel strips with a thickness of 0.15 mm. For thicker metal bands, two batteries collected in the diagram are required in parallel. The pulse time of the welding machine is adjusted, and ranges from 1 to 20 ms. This is enough for welding nickel strips described above.

The author recommends on the manufacturer to order. Order value 10 such boards - about 20 euros.

During welding, both hands will be occupied. How to manage the entire system? Of course, with the help of a foot switch. He is very simple.

But the result of the work:

In some cases, instead of soldering it is more profitable to use spot welding. For example, this method can be useful for repairing batteries consisting of several batteries. The soldering causes excessive heating of the cells, which can lead to their failure. But the point welding heats the elements is not as much as it acts relatively short time.

ARDUINO NANO is used to optimize the entire process in the system. This is a control unit that allows you to effectively manage the power supply of the installation. Thus, each welding is optimal for a particular case, and energy is consumed as much as necessary, not more, and no less. Contact elements here is a copper wire, and energy comes from a conventional car battery, or two if the current is required.

The current project is almost ideal from the point of view of the complexity of creating / efficiency. The author of the project showed the main steps of creating a system by posting all the data on the Instructables.

According to the author, the standard battery is enough for point welding of two nickel strips with a thickness of 0.15 mm. For thicker metal bands, two batteries collected in the diagram are required in parallel. The pulse time of the welding machine is adjusted, and ranges from 1 to 20 ms. This is enough for welding nickel strips described above.

The author recommends on the manufacturer to order. Order value 10 such boards - about 20 euros.

During welding, both hands will be occupied. How to manage the entire system? Of course, with the help of a foot switch. He is very simple.

But the result of the work:

The timer of the time relay is a device, with which you can adjust the time of exposure time, pulse. Timer Time Timer for Spot Welding Measures Exposure Duration welding current On the parts connected, the frequency of its occurrence. This device is used to automate welding processes, the production of welding seam, in order to create a variety of structures from sheet metal. It operates electrical load in accordance with the specified program. Programming time relay for contact welding in strict accordance with the instructions. This process is to set the time intervals between certain actions, as well as the time of the welding current.

Principle of operation

This time relay for point welding will be able to enable and turn off the device in a given mode with a certain frequency on an ongoing basis. If we speak easier, it makes it closing and opening the contacts. Using the rotation sensor, setting the time intervals in minutes and seconds after which you want to enable or disable welding.

The display serves to display information about the current time of inclusion, the period of exposure to the metal welding machine, the number of minutes and seconds before on or off.

Types of timers for spot welding

On the market you can find timers with digital or analog programmed. The relays used in them are different typesBut the most common and inexpensive electronic devices are. Their principle of operation is based on a special program that is recorded on a microcontroller. With it, you can adjust the delay time or inclusion.

Currently, you can purchase a time relay:

• with shutter speed;
• with a delay in inclusion;
• configured at the set time after the voltage is supplied;
• configured at the set time after the impulse supply;
• clock generator.

Component for creating time relay

To create a time relay timer for point welding, you will need such details:

• arduino Uno card for programming;
• the prototyping fee or Sensor Shield - ensures the relief of the connection, installed sensors with a board;
• wires for the type of mom-mom;
• the display on which at least two rows with 16 characters in the row can be displayed;
• relay carrying out load switching;
• the rotation angle sensor equipped with a button;
• power supply to ensure the supply of electrical current device (when conducting tests, you can power it via USB cable).

Features of creating a time relay timer for spot welding on Arduino board

For its manufacture, it is necessary to clearly follow the scheme.

While often applied fee arduino Uno. It will be better to replace on Arduino Pro mini as it has a significantly smaller size, it is cheaper and it is much easier to carry out the wires of the wires.

After collecting all component parts Timer for contact welding on Arduino need to solder wires that connect the board with the other elements of this device. All items must be cleaned from plaque and rust. This will significantly increase the operation time of the relay timer.

You need to pick up a suitable case and collect all the items in it. It will provide a device for a decent appearance, protection against accidental shocks and mechanical effects.

On completion, it is necessary to install the switch. It will be needed if the welding owner decides for a long time to leave it unattended to prevent fire, damage to the property in the event of emergency situations. With it, leaving the room, any user will be able to disable the device without much effort.

"Note!

Timer for contact welding on 561 is a more advanced device, as it is created on a new modern microcontroller. It allows you to more accurately measure the time, set the frequency of inclusion and turn off the device. "

Timer for 555 contact welding is not so perfect and has a trimmed functionality. But it is often used to create such devices, as it is cheaper.

To better understand how to create welding machine Contact employees of the company. In addition, we propose to consider the scheme for creating this device. It will help to understand the principle of the functioning of the apparatus, which and where it is necessary to solder.

Conclusion

The timer for point welding on Arduino is an accurate and high-quality device, which, with due operation, will serve long years. He is enough simple deviceTherefore, it can easily be mounted on any welding. In addition, the timer of point welding is easy to care. It works even in a firing frost, it almost does not affect the negative manifestations of the natural environment.

You can collect the device with your own hands or turn to professionals. The last option is more preferable, since it is guaranteed to provide the end result. The company will test the device elements, will identify problems, eliminate them, thus restoring its performance.