In detail: do-it-yourself repair of a redmond meat grinder from a real master for the site my.housecope.com.
It's easy to guess: there is an electric motor inside the meat grinder, supplemented by a rotation speed control circuit. If we set aside the cases when it is necessary to replace the protective sleeve, coupling, repairing meat grinders with our own hands concerns the knowledge of theory, the practice of operation of AC motors. In electric motors, collector designs are more often used by consumer electronics; in industry, asynchronous ones dominate. Newbies will ask where the authors got their information from. We answer: according to the Ariston service department, since the 90s of the last century, collector motors have been replacing asynchronous motors in the household segment. Today, the percentage of the former reaches 85 of the total. On this bright note, let's start looking at AC electrical machines and control methods.
One often hears the statement: brushed motors work equally well on AC and DC. Let's say more: the alternating current loses part of its power, passing through the stator and rotor chokes, the inductance tries to delay the frequency. 50 Hz is a bit too much for a simple lacquered wire spool. Often, the stator windings are driven out individually, as they are. You can power one. Power suffers, losses are reduced, reaching a minimum size.
How easy it is to regulate an induction motor. Found two methods used by meat grinders:
Changing the amplitude of the supply voltage.
Commutation of windings.
It is clear that the first method requires the inclusion of additional elements in the circuit. I would like to notice about this! I happened to read on the forum about the domestic speed controller of an asynchronous motor, as if there were only resistors. The author hinted at the presence of a resistive voltage divider. But! When the active element operates in a linear mode - most regulators are built by thyristors - the resistance is far from infinity or short circuit. They put radiators, protecting the semiconductor keys, we will touch on the topic below. We would like to bring to the attention of the reader: there will always be losses.
Video (click to play).
A little blood is not enough. The grinder device contains a motor with two windings, a starting capacitor, the rotor is represented by a drum, we see a 100% asynchronous motor with a squirrel cage rotor. Let's meet a circuit with switching windings. As follows. One coil is wound around the periphery, connected through a capacitor, providing the desired phase shift. The second is wound at an angle of 45 degrees around the circumference, there is no phase shift. One is divided by two unequal windings. Each can be switched on separately, in parallel (together). Gives three speeds.
Let's add asynchronous motors to the theme. The manual for the repair of meat grinders will forget to mention a trifle: a thermal fuse designed for 135 degrees is often placed inside the windings. Foreign elements are often decorated with the letter F, the number has little to do with Fahrenheit. Unlike Elenberg transformers, where the braid honestly writes: there is a thermal fuse inside, asynchronous motors are often devoid of mention. Call the windings: one suffers a break, patiently inspect for different elements hidden between the wire. It can be difficult to do, believe me. The first glance shows only copper, the second - copper, the third - an element of protection is noticed.
The thermal fuse is found, it should be evaporated, ringing. With a positive breakage test, get a new one, solder instead of the old one. Can you guess why you can't short-circuit? Right! The next time it is not the thermal fuse that burns out - the asynchronous motor, the hassle will increase.Similar radioelements are found in many products, there are no special requirements. Surely there is a suitable specimen at the flea market. Be careful not to tinker yourself. As is the case with the regulation of the speed of induction motors. The method of dividing the voltage by a thyristor is suitable; in practice, current cut-off is used.
The supply voltage is supplied bypassing the brushes in series on the rotor and stator. The direction of movement of the shaft is determined by the direction of the windings.
The current flows through a thyristor switch controlled by the sum of the voltages.
The source of the switching signal shaping determines the complexity of the circuit. Brush motors spark. When switching sections, a back-EMF occurs. Directed opposite to power supply. Apply feedback. Through a capacitor, the back-EMF diode is added to the thyristor control electrode. The more the amplitude, the less the gateway is open. The motor starts, or the load increases - the speed decreases. The amplitude of the self-EMF becomes less, the key current increases, and the engine returns to the mode. Needless to say, how important it is to keep the speed constant, the circuits solve this problem. It is clear that part of the power is lost on the key, the inevitable payment for stability. The speed can be adjusted separately via a variable resistor. Who is interested - you will find good options here
The meat grinder is open, we begin to inspect the engine. It is necessary to measure the resistive input resistance. If a capacitor is visible in the circuit, we define it as an open circuit, misinterpret it, considering it a breakdown. To repair the grinder yourself, check the proposed engine type. Traditionally collector, it is easy to recognize, thanks to the characteristic drum, broken by segments, two graphite brushes are diametrically adjacent. Asynchronous motors are sold with squirrel-cage, phase-rotor options. In the first case, the rotating part is devoid of electrical contact with the stator, the power source, in the second, there is a pair of rings supplying current to the rotor windings.
The difference between an induction motor with a phase rotor - the shaft is devoid of a segmented drum, there is no pair of brushes. Repair of electric grinders is carried out according to the type of engines. The asynchronous entry is ringing anyway. The collector engine is not enough.
We will ring the section, rotate the shaft, measuring the resistance of each step. The values must be equal. The process stops - the turnover is completed. In collector motors, the stator is often made on a single coil. It is connected to the rotor by a magnetic circuit, represented by a core with wire turns. Do-it-yourself meat grinder repair will be a freebie. Even if the wire is burnt in the center, always buy a roll of a new one with lacquered insulation in the store, wind the required volume with your own hands.
They use a device formed by two pairs of racks mounted vis-a-vis on a long board. Each has a rotating axle. One holds a new spool, the other holds a coil of wire. Here you wind up the old choke to localize the break, how many turns to wind, what is the length of the wire. Most people use a handle, like an old barrel organ, it is allowed to use a screwdriver drive, a drill. Determine the speed so that it is convenient to lay the turns tightly. With the shuttle, the other hand guides the wire from side to side, from edge to edge of the spool. In conclusion, we will ring the coil and measure the electrical resistance.
Repair of induction motors is determined by the design. The stator is repairable. The configuration of the rotor windings is complex (if any). However, if there is a lot of strength, time, desire to practice, it is impossible to stop the master. Let the day be spent, the engine again works as part of the meat grinder.
Winding direction.
Number of turns.
Location of terminals.
Three whales will help to correctly position the wire, it is allowed to combine it with neighboring coils, enlisting the help of soldering, applying insulation at the place of electrical connection.The main reasons for the breakdown of meat grinders are the consequences of improper operation. More often, there are two gross violations on the part of users of household appliances:
Exceeding the permissible time of continuous work, underestimating the duration of rest. The parameters are not advertised by manufacturers, not all meat grinders contain protection against overheating. Users are deprived of information about the features. Housewives are losing blenders. The motor breaks easily.
The second oversight is getting hard bones under the auger. Repair of the Zelmer meat grinder consists in replacing the protective sleeve. Sometimes you have to buy a set of spare parts.
Capacitors burn, swell (electrolytic on filters). Call, conduct a visual check: one side sticks out. The butt is pressed through with a cruciform recess. Bends outward. Burnt capacitor - consider a favorable outcome. Happy repair to everyone!
In this article, we will show you how replace the gear in the Redmond RMG-1203-8 meat grinder.
The manifestation of this malfunction is as follows: when you turn on meat grinder hums (sound motor audible), and there is no rotation of the auger drive.
First of all, you need to make sure that the meat grinder is disconnected from the mains.
Take off tray for meat
Press the release button auger body and disconnect the removable part from the meat grinder (auger body, auger, nut , lattice , knife ).
Turn the motor section over.
Unscrew self-tapping screws and remove the bottom cover.
We see before us grinder motor , electronic module and a gearbox with plastic gears inside.
Disconnect the connector power cord and the electronic module, after which we take out the gearbox.
Unscrew self-tapping screws connecting the gearbox covers and open it.
Before us are all the gears of the Redmond RMG-1203-8 meat grinder
We carefully inspect all three gears for damage. In our case, only the large gear is damaged.
It is also necessary to find any broken teeth and debris from the damaged gear and remove them.
It is worth noting that the cause of such a defect may be falling under screw bone parts from meat, as well as overload, since the meat grinder is designed only for chopping meat, and attempts to grind something else, for example, pepper, coffee, dried mushrooms, etc. will lead to breakage. Also, in no case can you use anything other than the standard one. pusher (knives, forks, etc.), as this will also lead to the failure of the meat grinder.
In the photo below, we see the absence of some of the teeth:
We take a new gear. When purchasing this gear in our store spare parts part code 18.12.107.01
We put grease on it and install it instead of the damaged one.
We collect meat grinder in reverse order.
We turn on the meat grinder to the network, check - in our case everything works fine.
The electric assistant today is very popular and in high demand among Russian buyers. Despite high-quality manufacturing and high reliability in operation, electrical appliances tend to break down over time. Many breakdowns can be repaired at home, so we will tell you in detail about the repair of an electric meat grinder, which you can easily do with your own hands.
It doesn't matter what kind of meat grinder you have - Kenwood, Zelmer or Moulinex, each of them has its own nuances, but the faults are pretty typical for all. Electric meat grinder repair specialists have compiled the following register of the main problems encountered in these products:
violation of various contacts of the electrical circuit;
deformation of the engine rotor;
breakage of the teeth of the gears of the reducer - arises from the increased load;
malfunctions of the electric motor, extreme wear of the brushes;
wear of the cutting tool due to the processing of too stringy meat, the ingress of small bones due to the user's oversight;
breakage of keys, safety devices;
damage to insulation, power cord;
replacing the motor or rewinding its windings.
Many failures of reliable technology are due to violations of operating conditions and only a few - a factory defect or a human factor during assembly.
If any malfunction occurs, it is necessary to immediately carry out diagnostics in order to find out the cause and localize the breakdown. Inspection of the mechanical part of the product is carried out visually, and the electrical circuits are checked with special devices. If a visual inspection of all parts of the mechanical part did not give a positive result, then you need to dismantle the product and inspect the gearbox, electric motor. May have happened clogged lubricant rubbing parts, the bearings do not work correctly, they need to be replaced.
Timely diagnostics allows you to identify and eliminate malfunctions at an early stage of their development, which significantly extends the life of the entire product.
Let's consider in detail the malfunctions of the meat grinder and methods of their correction.
The engine does not reach the set speed - the reason may be broken switch or the engine itself. Replace worn mechanisms or an electric motor.
Interruptions observed in the drive - extreme wear of graphite brushes, you need to install new ones.
Extraneous sounds, burning smell during product operation - defective engine... To restore it, you need diagnostics, repair or complete replacement. However, the cost of replacing the engine is quite high - it would be more cost effective to purchase a new grinder and solve the problem.
The reason for the appearance of sounds unusual for the normal operation of the meat grinder may be bearingsthat wear out during operation. To confirm the diagnosis, it is necessary to disassemble the main body of the product, get to the place of their installation and check the rotation, if necessary, replace it.
Reducing the speed of the electric motor - overload, the food is fed too fast, the meat grinder does not have time to grind them. The Kenwood mg model is particularly susceptible to this malfunction. Reduce the feed dosage and everything is normalized.
No shaft rotation - the transmission mechanism of the reducer is seized... Perhaps one of the gears or its teeth is broken and needs to be replaced.
The product auger has stopped. If at the same time the engine is operating in the same mode, then turn off the meat grinder and dismantle its mechanical part in order to find out the reason.
In the latter case, there are several reasons for the occurrence of such an unusual failure: incorrect assembly of the gearbox, cranking of the motor shaft, breakage of the drive gear teeth, and very rarely licking of the connection by the auger shaft (erasure of the hexagon).
On a note! The non-conformity of the metal of the part leads to its breakage during the ultimate load.
If the hexagonal receiver, where the auger shaft is inserted, is made by mistake of a softer metal, then during operation it quickly expands, or its edges wear off, the tight contact will be broken... The same can happen with the auger tip. It is difficult to repair a meat grinder with such problems with your own hands; the help of professional repairmen of similar equipment is required.
In order for the electric meat grinder to delight you with flawless work for a long time, you must follow simple recommendations for proper operation:
before starting work, always carefully check if the assembly is correct and reliable fixation of all parts;
pay special attention to the contact between the cutting tool and the grate - they must fit snugly, the fixing nut must be tightened with effort;
cut the product into piecesnot exceeding the diameter of the loading cylinder, in order to avoid them getting stuck;
disassemble, clean and rinse all parts and the internal volume of the meat grinder after each use;
keep all parts of the mechanical part of the product only disassembled.
Special attention! Before processing meat and fish, it is necessary to free them from bones, remove large veins, make sure that small bones that can damage the knives do not get inside the product.
Do not turn on the meat grinder without loading, do not try to push through the stuck pieces of food with your hands - there is a special pusher for this, never overload it. If you thoroughly fulfill all the requirements, then the product will work flawlessly for the entire period assigned to it by the manufacturer, and she will not need repairs with her own hands.