DIY sewing machine pedal repair

A sewing machine pedal often causes a “breakdown” of the electric drive. The sewing machine suddenly starts to stop periodically and only after a few presses “all the way” on the pedal resumes its course.
It happens that the sewing machine stops altogether, and even press the pedal with two feet, it will not work. The first thought that comes to mind in such a situation is that the engine “burned out”.
In fact, it was the sewing pedal that broke, not the electric motor. This can be determined if only because the engine, before “burning out”, lets you know about it. There is a strong smell of burnt electrical wiring, and he himself heats up no less than the iron.
Before deciding that the engine has "burned out", touch it with your hand, you can even smell it,

Actually, repair sewing machine pedals in many such cases, it is not needed, since the reason can be trite. The contacts of the connecting plugs are oxidized or the wire inside the insulation of the cord breaks. It is not difficult to eliminate oxidation of contacts, you just need to clean the contacts with sandpaper. But it is very difficult to find a wire break inside the wiring, and a tester is required.
A wire breakage inside the insulation occurs for various reasons, but mainly due to carelessness in the pedal connection wiring. This happens when you constantly pull the plug from the outlet by the cord or hit the cord with angular, heavy objects, such as the legs of a chair.
You can replace all the wiring without looking for a break. But this can only be done by an electrician, and even then not always, since the connecting plugs are often not disassembled, since they are cast at the factory along with contacts and wiring.

The only way out in this case is to buy a new pedal for a sewing machine, and sometimes complete with a motor, which is of course more expensive. See How to disassemble the clipper and replace the electric drive.
You will not be able to restore the wiring yourself, and most importantly it is pointless, since a break may appear after a while in another place. Once there is one cliff, then soon another one will appear. And in general, we categorically do not recommend repairing electrical appliances with your own hands. Electricity is a "serious" business and only a specialist should do such work.

The circuit of the sewing pedal of household machines that do not use electronics is very simple and is a switch, only in the form of a rheostat, which consists of many graphite round plates. The graphite parts of the rheostat “burn out”, a coating appears on their surface, which prevents the electric current. As a result of many years of long-term operation of the sewing pedal, the pedal fails them, although you will not find outward signs of this.
The only sign of this is when the slow speed of the car “disappears”. When the pedal has to be pressed “all the way” so that the sewing machine starts to work, and then immediately at the highest speed. This is a clear sign that you need to buy a new typewriter pedal.
If your machine has a pedal of approximately the same pattern, then you can move the rheostat body. This can adjust the smooth, jerk-free operation of the electric drive of the machine.

Electronic pedals for a sewing machine cannot be repaired sometimes even by a sewing machine repairman. Rather, the telemaster needs to do this, since inside she has a microcircuit and a board made of radio components and a circuit and different testers will be required. And by the way, these pedals, which are included in the set of many models of Soviet-made sewing machines, Chaika and Podolsk, very often break down.

Such a pedal stops working suddenly, but always at the most inopportune moment. On this basis, you will easily understand that the pedal has broken down forever. But seriously, inside the pedal the main radio component (thyristor) simply fails and therefore it suddenly stops working.
These pedals are easy to distinguish from others. They have a plastic body and are much lighter than other types of pedals as there is only one small board inside. Another difference is that the wire is mounted directly into the pedal body and cannot be disconnected, as, for example, for a sewing pedal to the TUR-2 electric motor.

Another sewing pedal often used in zigzag sewing machines such as Chaika, Veritas sewing machine, Podolsk. A very good pedal and comes with a TUR-2 electric motor, also of good quality. True, its fragile body often breaks, but this is not the fault of the pedal, but the mistress of the sewing machine, who treats her carelessly.

The body of this sewing pedal is very fragile, and the top cover is held by a slight bead on the lower body. Often, this protrusion breaks when struck or pressed hard by the foot and the pedal “opens up”. Here is the moment when you see how the pedal works.
You can fix this breakdown yourself, but you will need to restore the limiter in any way convenient for you. For example, glue or screw on a small plastic or metal stopper.

In order to disassemble this sewing pedal, it is necessary to pull out the sleeve that connects both halves of the pedal. It is easy to find where this bushing is, but to find out that it is also fixed with a screw is difficult. There is a hole in the middle of the bottom cover at the level of the sleeve, which is sealed with putty. Under the putty is the screw that securely grips the sleeve. Unscrew it and the grommet can be easily removed.
What is this secrecy for? Most likely, so that not everyone can disassemble a rather unsafe electrical device. I hope you also understand that disassembling electric pedals is dangerous.

After repairing yourself, do not leave the sewing pedal plugged in for a long time unattended. From inept adjustment of the rheostat, the sewing pedal can be in the on mode constantly and overheat.
If you take your foot off the pedal, there should be no voltage at the output contacts of the plug going to the electric motor, since the electrical circuit is completely disconnected. But, you can break this chain without knowing it.
Even when you take your foot off the pedal, a weak current will still flow to the rheostat. The chain is closing, but you will not understand it, since the sewing machine will be stationary. As a result, both the pedal and the electric motor will gradually heat up and heat up, and then you yourself know what happens.
Therefore, if you cannot check this with a tester, just make it a rule that any sewing machine, even a new one, should not be left unattended in an outlet, and even more so for a long time.

Well, and the last "rarity" that "our" typewriters have since Soviet times. Especially often such a pedal can be found in lockstitch sewing machines such as Singer, Podolsk. I don’t know who came up with this design, but the fact that using this sewing pedal is more comfortable with your thumb than your foot is for sure. Otherwise, it is a fairly reliable and “eternal” sewing pedal. And the wiring does not break inside her insulation. If you want it, you won't break it, such a thick wire. And the rheostat never burns out and it is quite difficult to even split the case. So, if it comes with the electric drive of your sewing machine, and do not expect it to serve for a long time.

The device of a modern sewing machine
How a modern household electric sewing machine works. Major malfunctions of components and mechanisms.

Sewing machine Veritas Rubina
The opinion of the master about which sewing machine is the best.Details about the used Rubin sewing machine and other old models of the Veritas brand.

Benefits of the horizontal shuttle
What are the advantages of the horizontal shuttle. How such a shuttle works, its possible malfunctions and how to fix them.

Sewing machine electric drive
Just like the pedal, the electric motor does not need to be repaired by yourself. Moreover, there is nothing to repair there. The engine is either running or not running. If it does not work, and you know for sure that there is no other reason for this, then it does not need to be repaired, but replaced. And to figure out when it needs to be changed, read this article.

Hand sewing machine - drive device and repair
If you have such a machine, then it can be converted. Instead of a manual drive, put an electric drive with a pedal. Buy the cheapest kit. Just do not confuse the motor rotation as the overlock motor rotates in the opposite direction. It is desirable that the pedal for the sewing machine is not the “cheapest” and has a ceramic body.

Foot sewing machine drive
The foot drive is difficult to use literally and figuratively. In addition, it knocks hard, which usually requires replacing the bearing. The best solution for a broken foot drive is to use it as a table and attach an electric motor to the machine. And then it will be possible to control the machine using a sewing pedal.

Sewing threads, which is better?
In order not to overload the electric motor and sewing machine pedal at the same time, use elastic and not too thick threads. Also, do not sew fabrics that are not intended for household sewing machines. From this, the electric drive experiences increased loads, heats up. And the first thing is the sewing pedal fails.

Sewing machine needles
How can the needle affect the operation of the sewing machine pedal? It is not just one thing that affects, but many factors in a complex. For example, thick coarse fabrics, a blunt needle with a curved point, continuous, non-stop operation of the engine, etc. All this causes the sewing machine pedal to “burn out”.

Do you have a sewing machine and love to sew? Then this site is for you. Professional craftsmen will tell you how to make minor repairs to a sewing, knitting machine. Experienced technologists will share the secrets of tailoring. Review articles will tell you which sewing or knitting machine to buy, a mannequin iron and many other useful tips you will find on our website.
Thank you for viewing the entire page.

Many people use electric sewing machines. It happens that electric drives of sewing machines, both domestic and imported, fail. Replacing an electric drive is expensive, but you can often repair an electric motor or a pedal yourself with your own hands, saving a lot of money.

There are many different electric drives for sewing machines, but the principle is the same. Below is one of them:

Electric motor Type MSh-2, 220V, 0.5A, 40W

Electric drives of types MSh-2 and MSh-2ER are designed for domestic sewing machines and some models of imported machines, overlocks and household tools (grinders, etc.).

• MSh-2ER:
• MSh - electric drive for sewing machines;
• 2 - modification number;
• ER - electronic voltage regulator.
• Climatic version UHL,
• placement category 4.2 in accordance with GOST 15150-69.

• The nominal values ​​of the climatic factors of the external environment are in accordance with GOST 15150-69.
• Indoor operation at ambient temperatures from 10 to 35 ° C.
• The environment is non-explosive, does not contain chemically active mixtures leading to the destruction of metal and insulation.
• Operation at a distance of at least 1 m from electric heaters.
• Storage in a dry heated room at temperatures from 1 to 40 ° C.
• Protection of a person against electric shock corresponds to class 2 in accordance with GOST 12.2.007. 0-75.
• Electric drives meet the requirements of TU 16-539.280-78.

• Rated voltage, V - 220
• Power supply frequency, Hz - 50
• Rated power, W - 40
• Rated current, A, no more - 0.5
• Electric motor shaft rotation frequency, min-1 - 6000 ± 1200
• Efficiency,% - 45
• Rated torque, Nm - 0.0635
• Electricity consumption, kWh - 0.1
• Weight, kg, no more - 1.8
• The operating mode of the electric motor is intermittent with a duration of up to 40% of the cycle time.
• The longest cycle time is 10 minutes: pause 6 minutes, work 4 minutes.
• The number of working cycles is not regulated.
• Smoothness of regulation is ensured when the drive is installed on the sewing machine.
• Mean time between failures - at least 300 hours.

The MSh-2 electric drive consists of a single-phase collector electric motor with sequential excitation with a bracket, powered by an alternating current with a frequency of 50 Hz and a carbon ballast rheostat.
The MSh-2ER electric drive differs from the MSh-2 in the presence of an electronic voltage regulator.
The regulation of the engine shaft speed is carried out by changing the voltage that occurs when the force of pressing the pedal changes.
The direction of rotation of the motor shaft is left, as viewed from the side of the output end of the shaft.
The overall, mounting and connecting dimensions of the MSh-2 and MSh-2ER electric drives are shown in the figure below.

Electric actuator MSh-2 (with carbon ballast rheostat)

MSh-2ER (with electronic pedal)

The first step is to remove the brushes. Try to do this carefully and slowly, the brush itself is connected to a spring and if you do not hold it, it can fly out, and break if it falls.

The brushes are removed with a screwdriver, you need to push the brush holder and rotate it 90 degrees.

Spring, retainer, graphite brushes

The condition of the brushes is normal, there are no cracks or chips.

Now you need to remove the pulley from the motor shaft. This is done simply, as shown in the photo, press on the latch and remove the pulley from the shaft. Again, be careful, the retainer is with a spring and can fly away, then you will look for a long time.

And here you can see how to install the pulley in place, insert the retainer into the hole on the shaft, press it down with a screwdriver and insert the pulley. The retainer, under the action of the spring, will enter the hole of the pulley and fix it.

It remains only to unscrew the screws and nuts and remove the case.

The year of manufacture is 1965, the old man is ancient, and apparently he was never disassembled, perhaps the brushes were changed. Over time, the bearing grease has dried out, so it gets very hot and hot.

If you press on the bearing base, then it will move away, we get good access for cleaning and lubrication, you can’t say anything, it’s convenient.

Here you can see what the grease has turned into over the years of operation, the bearing turns with effort. For the engine to function properly, all bearings must be kept clean and a good quality bearing grease must be used regularly. Deterioration in the lubrication of the bearing of the electric motor will be indicated by the following changes: deceleration of rotation or stopping of the bearing rings, its heating or melting. It is necessary to change the lubricant when it becomes dirty and a thicker consistency appears.

Before a complete change of grease, you must:

• flush the bearing with kerosene,
• fill in fresh grease.

Hands and tools (wooden or metal spatulas) must be clean. Fill the space between balls and clips with grease along the entire diameter.

We also lubricate the second bearing on the impeller side.

After some simple operations, the engine started up as good as new!

And here is the second engine MSh-2ER (with an electronic pedal). Didn't want to work, stopped periodically or didn't start.

Upon close examination, poor-quality soldering was found, there may be a factory defect, or oxidation of the solder as a result of improper operation. The wire was practically dangling, causing the electric motor to run unstably.

Soldering, soldering of engine elements

All parts and wire must be well tinned and soldered.
And don't forget about lubrication. It has already thickened a lot. Therefore, first we clean the bearing of the old grease and hammer in a new one.

The motor has started working stably, now it will have a long life!

The sewing speed is usually controlled by the pressure on the motor pedal. The engine and speed controller are connected to the electrical network using an electrical cord. The machine is started by pressing the speed controller pedal. More pressing corresponds to a faster sewing speed. After stopping the machine, remove your foot from the pedal to avoid unintentional starting.

There are many types of voltage regulators.
Basic types:

• carbon ballast rheostat.
• electronic voltage regulator.

The pedal with a carbon rheostat has an assembly of carbon pellets in a ceramic body. When you press the pedal, the tablets are compressed, as a result of which the resistance drops and the engine starts, the harder the tablets are squeezed, the less resistance and the higher the engine speed. The main malfunctions in such regulators, as elsewhere, are a malfunction of the cable, connectors, power plug. Carbon tablets often burn out, in this case it is necessary to replace the burned-out tablets. If they are not there, then you can carve them out of graphite brushes using a turbine and a file.

Pedal for electric drive MSh-2

The design is quite simple, there is a suppression device for interference from capacitors and chokes.

Pedal device. TOcapacitor, noise suppression

The electric motor stopped turning, but not immediately, at first it worked, then it did not work.
A very common reason is poor poor-quality soldering. The photo shows that the enameled wire coming from the choke before soldering was not cleaned of enamel and was tinned. They just hung up a snot, decided that it would work anyway.

I had to correct someone else's oversight, remove the solder snot, clean the enamel wire, and solder normally.

Recently I came across a pedal made in China.

It opens easily, just pry off the top cover of the pedal with a screwdriver.

Voltage regulation is stepwise, several speeds. Simple and reliable enough, it consists of a choke, a diode and a group of contacts.

There are few details, and there is nothing to break, it is possible that their diode fails or the contacts burn, sometimes the choke breaks.

Educational and educational blog about sewing machines at a professional level

I have exactly the same pedal, and the capacitor also burned out, can I directly connect the wires without a capacitor. I can't find a capacitor

If it were possible, without a capacitor, it probably would not have been put there. A capacitor is needed with such parameters. as in the video.

Tell me, is it possible to make the stroke of this foot smoother? Maybe through an additional rheostat?

Answer.

The course should be smooth anyway. If not, check the machine, it may wedge somewhere or the belt slips, weak. Need to tighten. Check it all out. Maybe the graphite tablets in the pedals are burnt, watch the video on the Podolsk 142 sewing machine No. 180 Part 2.

The instruction of the Chaika sewing machine can be used as an operating manual for any model of sewing machines that perform the Chaika zigzag stitch: Chaika 2, Chaika 3, Chaika 134.

This instruction for the Chaika sewing machine is also suitable for the Malva sewing machines and the Podolsk brand: Podolsk 142, Podolsk 142M, etc.

These operating instructions for the sewing machine are given in abbreviated form, based on the manufacturer's instructions.
The operation and device of the Podolsk and Chaika sewing machine is practically the same type, therefore this operating manual is suitable for all models of these sewing machines, including the Malva sewing machine. They have the same structure and differ only in the presence of additional types of zigzag stitching. Some Chaika and Podolskaya models have an additional device (copier) for this and, accordingly, a lever for switching modes of its operation.The shuttle device, threading and adjustment parameters of the units and mechanisms of these sewing machines are practically the same, with the exception of setting some settings for the shuttle operation parameters (depending on the machine model).
For details on how to set up and perform minor repairs of sewing machines like the Seagull, see other articles in the section dedicated to the repair of sewing machines.

1. Shuttle device. 2. Platform. 3. Stitch plate. 4. Pressing foot. 5. Needle bar. i6. Presser foot lifter. 7. Upper thread tension dial. 8. Top and front covers. 9. Thread take-up lever. 10. Tension washers. 11. Index of the type of stitches. 12. Zigzag width indicator. 13. Spool pin. 14. Winder. 15. Flywheel. 16. Needle bias lever. 17. Zigzag handle. 18. Lever for reverse feed. 19. Knob of the stitch length regulator. 20. Knob of the comb lift regulator. 21. Material engine. 22. Panel of pictures. 23. Knob for switching the copier unit.

Fine silk, cambric - needle No. 70, thread - 65
Bed linen, calico, chintz, satin, silk, linen fabrics - needle No. 80, thread - 65
Heavy cotton fabrics, coarse calico, flannel, fine woolen fabrics, heavy grades of silk - needle No. 90
Woolen suit - no. Needles 100
Thick woolen coat fabrics, broadcloth - needle No. 110

Needle 1 must be inserted into the needle holder 2 (at the upper position of the needle bar) up to the stop and secured with the screw 3.
The flat side of the flask 4 (flat) on the needle should be facing in the opposite direction from the working person (Fig. 4)

Threading the upper thread
Pull the spool pin 13 up to the stop from the sleeve cover.
Bring the thread take-up eye to the upper position by turning the handwheel.
Raise the presser foot.
Place a spool of thread on spool 13.
Thread the upper thread in this sequence. Into the holes 7 and 6 of the thread guide, between the washers 8 of the tension adjuster, then upwards into the eye 4 of the take-up spring, down under the thread take-up hook 3, up through the hole of the thread take-up lever 5, down into the thread guide 2, into the thread guide 1 on the needle bar and insert into the eye needles 9 from the side of the worker.

Threading the bobbin thread
Before threading the bobbin thread, you need to remove the bobbin case with the bobbin from the bobbin, for which it is necessary to turn the handwheel to bring the needle up. Pull out the slide plate, grasp the bobbin case latch lever with two fingers of your left hand, and remove the bobbin case.

Wind the threads onto the bobbin using the bobbin winder. When winding thread onto a bobbin, the handwheel of the machine must be idling. To do this, loosen the friction screw 1 (Fig. 8).
Slide the bobbin onto the bobbin spindle 2 so that the spindle spring enters the bobbin slot. Place the spool 1 with thread on the spool pin. Thread the thread from the spool between the tension washers 4, as shown in Fig. 9, and then wind a few turns on the bobbin by hand. Press the winder against the flywheel. Next, wind up by rotating the flywheel using the drive.
When the bobbin is fully wound, the rubber ring of the winder stops contacting the flywheel and winding stops. Before removing the bobbin, the winder must be swiveled to the left of the stop 3.
Thread the wound bobbin into the bobbin case and thread under the tension spring as shown in fig. 10. Leave the free end of the thread 10-15 cm long.
Insert the bobbin case with the threaded bobbin into the hook. In this case, the needle should be in the upper position.
Push the bobbin case with the bobbin onto pin 3 of the bobbin as far as it will go. In this case, the pin 1 of the bobbin case must enter the slot 2 (fig. 11).

To ensure easy running of the machine and prevent wear, all places indicated by arrows should be lubricated with one or two drops of industrial oil I-20A GOST 20799-75.
Machine head lubrication points (fig. 17)
Zigzag lubrication points (fig. 19)
Cleaning and lubricating the shuttle (fig. 20)
Heavy movement of the machine, and sometimes jamming, can occur from contamination of the shuttle stroke. The course is clogged with scraps of thread, fleece, dust.
See also Sewing Machine Lubrication
To clean the shuttle stroke, the needle bar must be in the upper position. Pull out the bobbin case 1, by turning the spring lock towards you, remove the trim ring 2, take out the hook 3. Carefully clean the nest of the hook 4 with a brush-brush from dust, dirt and threads. In this case, it is not allowed to use metal objects for cleaning, so as not to damage the cleanliness of the working surface. The direction for the hook in the travel housing and the winder spindle are also lubricated with 1-2 drops of oil.

The Chaika sewing machine is perhaps the most popular model of a sewing machine for the home, despite the abundance of imported household sewing machines in stores. At one time, I had to buy Seagull for a lot of money, and it seems to sew well, but only sometimes it twists, otherwise everything is safe and sound. Indeed, it is almost impossible to break the Chaika sewing machine. The body is made of aluminum, the parts are all metal, the components are strong and reliable - everything is in the style of Soviet technology. But here, unfortunately, the line loops
practically “from birth”, sometimes gaps appear in the line, especially on the zigzag and knocks when sewing like a machine gun.
The manufacturer encloses instructions for the Chaika sewing machine in the kit, where it is detailed how to use the machine and perform various operations, there is even an electric motor circuit, a pedal device, but not a word on how to set up and perform at least minor repairs of the Chaika sewing machine. We will try to fill this gap in the instructions and give some recommendations on how to repair the Chaika sewing machine with our own hands.

The main malfunction in machines of the "Seagull" type, performing a zigzag stitch and, on its basis, several types of finishing stitches are gaps, looping of the lower and upper thread, as well as its breakage at the top and bottom. Sewing machine Chaika, Chaika M, Chaika 142, Chaika 132, Chaika 134, Chaika 132 m, Chaika 142 M, Chaika 143, Chaika 3, Chaika 2 and Podolsk 142, Podolsk 125-1; Malva and others - all these machines have the same device and instructions for use and adjustment, so their repair is almost the same, with the exception of copier repair (depending on the machine model) and setting the shuttle settings. But since our task is to learn how to customize only a line, we will omit the repair of many nodes. In addition, such repairs cannot be done with your own hands, without professional knowledge and experience at home.

Before proceeding with the repair and adjustment of the Chaika sewing machine on your own, it is advisable to do a routine inspection, cleaning, and lubrication. To do this, disconnect the electric motor from the mains, remove the top cover (it is fastened with two screws). Detach the foot, remove the needle and stitch plate, and the bobbin cover. Detach the clipper from the wooden stand or table. Disassemble the bobbin: bobbin case, locking ring, hook. Now remove dust, dirt, fleece from the machine (especially in the shuttle section) and lubricate all rubbing accessible places with machine oil well. Use a tough small glue brush to clean, and a medical disposable syringe is very convenient to lubricate the sewing machine.

Thread breakage often occurs with sewing machines such as the Seagull. The first reason leading to thread breakage is a bent needle point, which breaks the thread during its movement. With the help of a magnifying glass, the state of the needle point is very clearly visible. Use needles that are in good condition and intended only for household sewing machines, in accordance with See instructions for the sewing machine Chaika, Podolsk 142
Sewing machine needles must be in perfect condition.The condition of the needle can be determined by running your fingernail along the tip of the needle or using a magnifying glass. Often it is the needle that causes gaps in stitches, needle breakage and other stitching defects.
Select the needle number according to the thickness of the fabric and thread. Do not use home sewing machine needles with a round bulb. Household sewing machine needles have a saw cut on the flask.
For sewing various fabrics and materials, use the appropriate type of needle, for example, for sewing leather, the needle has a four-sided point, which makes it easier to pierce the material and contributes to the formation of a loop on the needle when it is caught by the nose of the shuttle.

Thread breakage can be the result of many malfunctions, for example, if the needle touches it when entering the needle hole, then the thread will periodically break. When sewing a straight stitch, the needle should be in the center of the hole in the needle plate, evenly spaced from its sides, and when performing a zigzag operation, the distance L should be the same with R.
The longitudinal installation of the needle in the center of the needle gap is carried out by displacing the needle bar frame, fixed with two screws on the rocker, in the upper part of the machine (turn the handwheel on the zigzag line and you will see this attachment). Loosen these screws and set the needle on a straight stitch exactly in the center (by moving the needle bar frame). Then check the position of the needle at the left and right injection. The entry of the needle (at the maximum zigzag width), on the right and left, will be evenly spaced from the center. If the needle touches the edge of the hole at the maximum width of the zigzag, contact the master, this case is already for him.

The transverse position of the needle is adjusted by a rod, fixed on the plate with two screws, and a plate that presses the needle bar frame to the rod of the bracket.
The adjustment of this unit is quite complicated and requires experience, but, unfortunately, it is this mechanism that can spontaneously get lost during operation, especially in electric sewing machines. Therefore, if you decide to independently repair the Chaika sewing machine, you should learn how to adjust this position of the needle, since the forward displacement of the needle is the cause of its breakage, and the displacement towards the seamstress is the cause of omissions.
Adjusting the crosswise position of the needle requires professional knowledge and experience. If you are not sure that you can do it yourself, contact the master, since the wrong position of the needle can be the cause of misalignment of other nodes, the repair of which cannot be learned from a boring book stuffed with technical terms and diagrams.
Pay attention to the condition of the stitch plate. Hole e must not be “broken” or jagged. It is better to replace such a plate.

This is an electric drive of Polish production and the main part of sewing machines of domestic production and not only was equipped with it. In this article, we will look at how to repair an electric drive.

Correctly it was called - "Home sewing machine drive kit", but we will call it an electric drive. At one time, the Household Sewing Machines of the Podolsk plant were equipped with this drive and it has proven itself very well. During perestroika, some masters sewed on our sewing machines "Chaika", "Podolsk" for almost days, even put it on the 22nd grade, and this drive "endured" everything.

In fig. 1 shows a set of electric drive for a sewing machine.
1. Pedal rheostat type
2. Electric cord
3. Electric drive
4. Belt
5. Mounting bracket
6. Lighting cord (also called a whip)

The electric cord has three ends:
1.plug, to be connected to an outlet;
2. Two-pin plug for connecting to the pedal;
3. Three-pin plug for connection to the actuator.

Before disassembling the housing of the electric drive (3), it is necessary to dismantle the bracket for attaching to the sewing machine (1), for this you need to unscrew two screws (2), see Fig. 4

On the bracket, at the point of attachment to the drive and to the sewing machine, plastic spacers of a special configuration are installed. For machine type "Chaika" they are installed as in fig. 5. for machines PMZ class. 2M, they need to be installed the other way around.

To remove the plastic case, you need to unscrew the four bolts, see fig. 6.
Attention. The side with the bolt holes is the bottom of the actuator.

After unscrewing all the bolts, turning the case over with holes on the palm of the left hand, remove the top cover with the right hand, see Fig. 7

Figure 8 shows the external view of the drive with the cover removed. Here:
1 is the bearing bracket assembly,
2 - the body where the brush with the spring is attached,
3 - brush apparatus (lamellas),
4- stator winding. The lamellas burned out from a short circuit are shown on the brush apparatus.

A close-up of the lamellas is shown in Fig. 9
To remove (dismantle) the rotor of the electric drive, it is necessary to bend the plug on the body of the brushes and pull out the brushes with springs, unscrew the six bolts indicated by the jackdaws in Figure 8.

Next, you should unsolder the wires from the body of the brushes, but you don't need to unsolder if you only need to replace the rotor. Lift the right side of the stator as in fig. 10 and take out the stator assembly to the right. By the way, the figure clearly shows that one wire on the socket is broken off (thin green).

In fig. 11 shows the bolts and brackets for fastening the bearings (1) and a special washer, fastening the stator iron (2) to the housing of the electric drive.

To remove the front bearing race, you must:
1. Unscrew the screw 3 and pull the pulley (4) to the right from the plastic part, usually it is very tight;
2. Pull the plastic part (2) to the right, if it is held very strongly, then you can slip tweezers or something conical;
3. Remove the bearing housing (1) and one or more washers. One of them will be curly. See fig. 12

Often a malfunction occurs due to the fact that the contacts on the housings of the brush holders are poorly soldered, Fig. 13. Therefore, it is better to solder them, it is necessary to solder by bending the soldering points upwards so that tin does not get into the case.
By the way, if you change the ends of the windings in places, the engine will spin in the opposite direction. P. S. When installing this drive on a 51 class overlock, this is relevant.

Figure 14 shows two rotors, the upper one burned out, the lower one new. Why I do not advise you to rewind the rotors, if you look closely at the lower rotor, you will see a gray plaque, on the upper one it is simply not visible. It was the rotor that was balanced at the factory, when rewinding, they cannot always balance and the electric drive can quickly fail.

We install the rotor in place in the same way as it was removed. Lift the stator winding at an upward slope and start the rotor from right to left. See Fig. 15. If, after fastening the bearing races, the rotor does not spin well, remove one or more washers and try again for ease of movement.

The last we tighten the bolts of the stator winding, see fig. 16. The operation is performed in such a way that the rotor does not touch the stator anywhere and is exactly in the center of the stator iron.

It's time to put the brushes in place, for this we fix the brushes on the spring and insert them into the socket, squeeze the spring and, holding it with a screwdriver or tweezers, bend up the tide on the brush holder body. See fig. 17.

All that remains is to put the housing cover back in place and secure it with four screws.
Let's take a look at the electrical outlet of the electric drive shown in fig. 18. We see here two bolts, they are pressed against the wires from the wiring for lighting. If the wiring is not needed, then you need to slightly unscrew these screws (2) and the plastic screw (1) and pull out the whip. Remember to tighten the screws (2). See fig. eighteen.

So we assembled an electric drive for a sewing machine, manually checked the ease of movement (MANDATORY), then assembled the entire electrical circuit and checked the operation of the engine in all modes when voltage was applied.

Now let's move on to the pedal.

The pedal of the TUR 2 electric drive is quite strong, but it still must not be dropped or kicked on it. The case is strong, but fragile and, as a rule, it is not possible to glue it. The pedal is always black.

At the bottom of the pedal there is a hole in which the head of the bolt is located, with which the stud securing the parts of the pedal body is fixed. There is usually a warranty seal in this hole. Sometimes this bolt turns and the pin cannot be pulled out until we unscrew the screw. In this case, we do this: we press on the stud with a screwdriver or other object and at the same time unscrew the bolt without pressing on it. If you are lucky, then you will slightly unscrew the bolt and you will be able to pull out the hairpin, if not, then just drill. In my case, the stud stop was enough. Rice. twenty.

Use a screwdriver or other cylindrical object of a smaller diameter to push the pin out, fig. 21. On the side opposite to the hairpin, you can see the bracket that holds the upper part of the pedal in the extreme upper position.

Holding the body products, carefully lift the upper part of the pedal from the narrow side. Make sure that the spring does not jump out and hurt you. In fig. 22 shows the inside of the pedal
1. A bump in the upper part of the pedal, where the second end of the spring rests;
2. The tide, with the help of which, when you press the pedal, the movement of a special device that closes the electric circuit occurs;
3. A special plate that closes the contacts (6) and the pedal starts to work straight, i.e. like a button;
4. Fastening pin;
5. The spring that opens the body products;
6. Special L-shaped plates, with thread for the adjusting screw. The ends of the wiring are soldered to these plates.
Attention - metal is fragile.
7. Resistance;
8. Screw with nut. When the nut comes out of the socket, the screw cannot be removed.

One of the main parts of the pedal are two cases (1) filled with carbon heels. These cases are fixed in the case with a special bracket (2). From the rash of these heels from the pencil case, there are L-shaped plates (3).

We unscrew the screw securing the staples of the pencil cases, remove the pencil cases. In fig. 24 shows the details of the canisters. And in fig. 25 coal heels themselves close up. If these heels already have a heel surface, then you can do the following: Take a glass, put a clean, even sheet of paper on it and gently rub the heel with one side and the other. If you are not sure, then it is better to assemble it as it is. If the heels are broken and they are not enough, then you can add a metal washer (s). We've checked everything, collect your pencil cases. You need to collect in an upright position, several heels, shaking the case of the pencil case so that the heels do not stand on the edge. We put the last washer with the recess outward.

After assembling the pencil cases and installing them in place, everything should look like in Figure 23.

But now we will put in place the device for activating the pedal. Often, with self-repair, they will do it here so that only parts need to be changed. See fig. 26. Here we see a recess (1) in the body, the lower end of the device is installed into it with its sharp tides from below. The copper contact, riveted to the device, rests on the carbon cylinders, which are the first in the case.

Now we put the spring on the device as shown in fig. 27. Holding the switching device with a finger, put on the upper pedal cover so that the spring hits its own tide, and the triangular tide presses the switching device.

If nothing came off during assembly, insert the hairpin into place. Now we check the pedal operation. The pedal should work as follows. When you press the pedal, the engine should start moving after a while. That is, the upper part of the pedal should drop by about 1 cm. At the same time, the engine rotates slowly, well, as if about 120 - 140V was applied to the stator winding. When pressed further, the engine speed should increase smoothly to the maximum speed.Only after checking, tighten the stud fastening screw.

Let's go back to the view of the pedal with the cover removed. The number 4 here marks the adjusting screws, which are sealed after adjustment.

So we repaired the electric drive, at the same time we revised the pedal.