Process name

Precautions

Rotor press

Before pressing

1. First check whether the selected tooling and parts are correct.

2. Check whether the rotor punching burrs are qualified, and those with too large burrs will be taken off-line for processing.

3. Whether the size of the rotor shaft punching ribs is appropriate.

4. The end face of the commutator and the mica sheet must not have burrs, skew, and the mica sheet is evenly slotted, and there is no breakage of the hanging wire buckle.

When pressing

1. Operate strictly according to the regulations: the stroke and pressure adjustment of the hydraulic press are appropriate. In order to prevent the shaft from bending (check the runout of the journals at both ends ≤ 0.02mm), the press-fitting size is out of tolerance.

2. The commutator cannot be crushed or cracked.

After pressing

1. Check whether the press-fitting size of the iron core meets the design requirements.

2. The straight chute is pressed accurately (the hook on the ZYT-13X series commutator must be aligned with the center of the core slot).

3. The end face of the iron core must be flat, free of shaft flowers and looseness, and there is no dirt in the groove.

Analysis of common defective products:

1,The stack height does not meet the regulations: affecting the performance of the motor

⑴The number of chips is large

⑵Many chip burrs

2. The size of the press fit is out of tolerance; it affects the performance of the motor and the assembly of the motor

⑴ Improper stroke adjustment of hydraulic press

⑵The positioning tooling is not adjusted properly

3. Axis bending: cause the shaft to run out of tolerance and cause shaft noise

   ⑴ Improper force on the shaft during the press-fitting process

4. The commutator bursts or has cracks, causing the rotor to be scrapped and cannot be used

   ⑴ Excessive oil pressure

Rotor winding

before winding

1. First check whether the selected winding die and enameled wire are correct; when the enameled wire passes through the wire, it must be ensured that each wire passing wheel rotates well, and there is no peak in the wire passing way to prevent wire damage.

When winding

1. The position of the iron core is correct up and down and in the circumferential direction, and there must be no looseness. The first hanging wire buckle must be accurate. For specific positioning, see the operation documents of each motor.

2. It is found that there are chips hanging on the enameled wire, and the phenomenon that the insulating paper of the slot is rolled inward. It should be stopped immediately for processing, and the enameled wire should not be accidentally damaged.

3. The length of the hanging wire is appropriate, no missing hanging, and no damage to the enameled wire.

4. When winding, the end of the coil should be close to the inner side. If necessary, the scribe piece can be placed on the enameled wire at the end, and then tapped lightly with a rubber hammer to make the enameled wire at the end close to the rotor shaft. In short, the enameled wire should be wound well. Compact and docile.

5. When replacing the enameled wire, you must pay attention to check the wire passing method and winding method.

After winding

1. When inserting wires of ZYT-90/120 series rotors, the enameled wire must be completely pressed into the inserting groove to prevent it from falling out.

2. Before shaping, check the arrangement of the enameled wires at both ends of the rotor: (1) For windings far away from the rotor sheet, there is no need to tap and shape; (2) For windings close to the rotor sheet, which will affect the groove wedged into the groove, lightly tap and shape toward the center of the rotor slot. .

3. When the groove is wedged into the groove, if there is enameled wire warping in the groove, use the groove wedge to press down the wire first, and then insert the groove wedge; the groove wedge cannot be skewed, broken and exposed evenly.

4. The wire at the end of the rotor after shaping must not be higher than the notch, and the shape should be beautiful and beautiful, and the direction of the wire should be neat and consistent. There must be no collision, and the paint film of the enameled wire shall not be damaged.

Analysis of common defective products:

1,Line height: cause the rotor to rub against the casing

(1) Improper adjustment of winding machine

⑵ Winding tension is too small

2. Line damage: cause electric leakage of the motor

   ⑴There are peaks in the enameled wire passing path

⑵ Damage to the enameled wire paint film during plastic surgery

3. Thread loosening (expansion): affects the subsequent process and easily causes thread damage

⑴Winding tension is small

⑵The enameled wire is not over-tensioned and the wire wheel is installed

4. Missing and hanging wires, embedding wrong wires: resulting in poor performance of the motor

   ⑴Human error

Rotor spot welding

1. The spot welding head of ZYT-90/120 series rotor is conical, and the tip is φ0.5 plane.

2. The spot welding head of the ZYT-13X series rotor is flat and square.

3. The welding is firm and the solder joints are beautiful. The connecting lines cannot touch each other between the two mica grooves.

4. Gently pull the enameled wire by hand, and there should be no loosening of the solder joints; each wire end should be able to withstand 4kg of static tension for 1min without falling off. In order to prevent weak welding and false welding, ZYT-13X series rotors must be welded twice if necessary.

Analysis of common defective products:

1,False welding: the motor is not powered

(1) The pressure is too small or the spot welding current is too small during spot welding

2,Excessive paint stripping length: short circuit in adjacent windings

⑴ spot welding current is too large

3.Short circuit: lead to high motor current, easy to burn the machine

(1) When the commutator is spot-welded, the solder joints are crooked or the copper sheets are crushed, and two adjacent copper sheets are squeezed into contact

⑵Enameled wires of adjacent windings at the embedding groove (hanging wire buckle) are too long and contact

Rotor detection

1. Check the armature according to the standard waveform drawn in the "Armature Tester Operating Regulations".

2. ZYT-90/120 (180VDC) series rotor withstand voltage standard: 1500V (50Hz)/5mA/1S without breakdown.

3. ZYT-13X (12VDC) series rotor withstand voltage standard: 500V (50Hz)/5mA/1S without breakdown.

4. When the rotor is running, the operating lever cannot be pressed down to prevent the rotor from flying out and hurting people.

Analysis of common defective products:

1,Short circuit: cause the motor to burn out

(1) The solder joints are crooked during spot welding, and the copper sheets are rotten due to welding, causing adjacent copper sheets to contact

(2) The paint stripping length is too long, and the adjacent windings are in contact

2,Open circuit: causes interruption of motor function

⑴ Missing and hanging wires during winding

⑵Knock off the thread during the shaping process

3.Bad turn-to-turn: short motor life

⑴ There is a wire injury during the winding process

4. Poor high voltage: lead to electric leakage of the motor, endangering personal safety

⑴The enameled wire is in contact with the core piece

Rotor dripping paint

1. The paint must be prepared according to the proportion of the manual.

2. The rotor preheating and drying temperature and time must be guaranteed.

3. The enameled wire at the front and rear ends of the dried rotor should not have a single wire jumping phenomenon.

4. The dripping paint must be dripped evenly until the rear end of the commutator is completely covered with paint; the effect of dripping paint is that the insulating paint on the rotor winding is evenly distributed, and each enameled wire is wrapped with a layer of paint.

5. There must be no residual paint on the surface of the two bearing gears and the commutator.

Analysis of common defective products:

1,Poor effect of dripping paint; resulting in poor rotor winding insulation and poor motor performance

(1) The rotor preheating temperature is not enough and the time is short

⑵The insulating paint is not prepared according to the process requirements

(3) The drying time of the rotor is short and the temperature is not enough

⑷The process of insulating paint dripping is well controlled

2. There is residual paint on the surface of the rotor: it affects the assembly or causes the motor to stall

   ⑴The tooling was not adjusted properly when the paint was dripping

Rotor dynamic balance

1. The left and right V-shaped brackets of the balancing machine should be parallel.

2. The ratio of plasticine must be adjusted 1:1

3. There must be no residual paint on the outer circle of the rotor core, the shaft and the commutator.

4. Plasticine should be added to the outer part of the rotor winding, and should not be higher than the outer circle of the rotor.

Analysis of common defective products:

1,Large weight loss: resulting in large vibration of the motor

⑴The angle of adding balance mud is wrong or the quality of adding balance mud is small

2,Balanced mud fly: cause the motor to stall

⑾ The balance mud is not compacted

3. Balance mud height: cause the rotor and the casing to rub firmly

⑴ The position of the balance mud is improper or not flattened

Rotor fine turning

1. Operate according to the "Operating Regulations for Commutator Finishing Machine", first rough turning and then finish turning.

2. The end surface roughness of the ZYT-13X series rotor commutator must reach Ra0.8 or above, and the verticality is less than 0.01mm.

3. The finish surface roughness of ZYT-90/120 series rotor commutator must be above Ra0.8, and the cylindricity should be less than 0.015mm.

4. There is no copper powder in the commutator slot, and the mica sheet must not have roughness.

5. When removing the copper powder (foam) on the surface of the commutator, be careful not to scratch the finished surface of the commutator, otherwise it must be finished again.

Analysis of common defective products:

1. Short turning length: resulting in motor noise or large sparks

   ⑴The horizontal stroke of the finishing machine is not enough

2. The outer circle (end face) of the finish car exceeds the requirements: the performance of the motor cannot meet the requirements

   ⑴The feed rate of the finishing machine is not adjusted properly

3. The shape of the pattern is poor, and there are obvious ring knife patterns: resulting in motor noise, large sparks, and unstable performance

   ⑴The turning tool is broken or the finishing machine is unstable

4. There is copper powder in the commutator slot: cause short circuit and burning of the motor

   ⑴The turning tool is improperly adjusted or the turning tool collapses

   ⑵Human error

5. The surface (end) of the commutator jumps greatly: causing motor noise, large sparks, and unstable performance

   ⑴The V-shaped frame has peaks or foreign objects

6. Shaft flower: the motor does not run smoothly and the motor makes noise

   ⑴The V-shaped frame has peaks, the belt pressure of the pressing arm is too large, and there is no oil lubrication

7. Shaft bending: causing the motor to run unsmoothly and making noise

   ⑴The belt pressure of the pressure arm is too large

Process name

Precautions

Stator made

Before bonding

1. First check whether the selected tooling and parts are correct.

2. Check whether the magnetic steel is qualified, and those with cracks or broken ones will be taken off the assembly line. Check whether there is any dirt on the inner surface of the magnetic steel and the casing, and blow off the dust with an air blower for later use.

3. Whether the positioning size of the tooling is appropriate.

4. Test adhesion before mass production (no glue application for now), and continue after passing the first inspection.

When bonding

1. Operate strictly in accordance with the regulations of the operation document.

2. The polarity of the magnetic steel cannot be confused and the paste must be firm and reliable, and there must be no displacement or dislocation.

3. The A:B formula of "AB glue" is 1;1.

After sticking

1. Let it stand still until it is completely solidified and firm before moving.

Analysis of common defective products:

1. The positioning size does not meet the requirements: resulting in poor performance of the motor

   ⑴ Improper selection of tooling

2. The magnetic steel has displacement and dislocation phenomenon: it leads to the deterioration of the performance of the motor

⑴The glue is not fully cured, it will move

3. There is glue at the mouth of the casing: it affects the motor assembly and noise

⑴Human error, not dealt with in time

4. The polarity of the magnetic steel is sticky and reversed, causing the motor to reverse

   ⑴Human error, wrong polarity identification

Process name

Precautions

Manufacturing of end cap components

Pressure (oil) bearings

1. First check whether the selected tooling and parts are correct

2. Check whether the end cover and bearing are qualified. If there are cracks or broken, go offline for processing; if there is any dirt on the inner surface of the end cover and bearing, blow off the dust with an air blower for later use.

3. When pressing, you must operate according to the "Press Operating Regulations".

4. The adjustment of the press is moderate, that is, about 0.5MPa, and it should not be too large to prevent the end cover from being crushed.

5. The bearing must be pressed to a limited position.

Brush assembly, brush holder installation

1. When installing the brush assembly, the direction of the lead wires at both ends of the terminal must not be confused.

2. The installation of the brush holder is firm and reliable, and the inner holes of the corresponding two carbon brush boxes are on the same straight line; the mandrel can move flexibly.

3. The brush assembly can move flexibly and freely in the brush holder without any blockage.

4. When ZYT-13X series installs the carbon brush assembly, the direction of the lead wires at both ends of the terminal must not be confused.

5. The ZYT-13X series brush grip is tightened with moderate force to ensure reliable fastening without loosening.

6. All washers and springs must not be missed or wrongly installed.

Analysis of common defective products

1. Deformation and breakage of end caps and oil bearings: lead to scrapping of parts

⑴The pressure of the press is too large

2. The electric brush is stuck: it affects the motor assembly, and the spark is large

⑴ Improper clearance between the brush and the brush holder

3. Cracks and broken brush holders: affecting motor assembly and scrapping parts

⑴The tightening force is too large when the brush grip is tightened

Process name

Precautions

Assembly

Inspection before assembly

1. First check whether the selected stator, rotor and end cover components are correct

2. Check the stator, rotor and end cover components for dirt, and blow off the dust with an air blow gun for later use.

Assembly

1. The ZYT-13X series motor should be installed with symmetrical force, the front and rear end covers should be installed in place, and there should be no gaps around the joint between the end cover and the casing. The front and rear end caps are aligned with the housing (torx) shape.

2. When assembling ZYT-13X series motors, attention should be paid not to shift the armature assembly upward due to the suction force of the magnetic steel, causing the carbon brush to run out of the brush holder hole.

3. When assembling the ZYT-132D motor, use tweezers to put the four springs on the two hooks of the brush holder in turn. Adjust the spring to ensure that it is in the middle of the notch, so as not to damage the spring.

4. The polarity of ZYT-90/120 series motor carbon brushes should be clearly distinguished when installing.

Machine detection

1. The power supply voltage for the test system is properly selected.

2. Whether the rotating shaft end is flexible and free of blockage.

3. Monitor the running sound of the whole machine, there should be no abnormal sound.

4. Do not confuse the positive and negative polarities when connecting the power supply and the motor.

5. Check the rotation direction of the motor. ZYT-13X series motors should run counterclockwise when viewed from the output shaft end, and ZYT-90/120 series motors should run clockwise.

6. The effective value of brushing sound, spark level and vibration speed must be judged or tested accurately (can be compared with standard parts).

7. ZYT-90/120 series motor no-load spark level standard: ≤5/4, when the spark is large, use metallographic sandpaper (green 600 mesh) to lightly polish the commutator commutation surface.

8. Qualified motors are sent to the grinding brush table for grinding: about 5 minutes for ZYT-13X series motors; about 30 minutes for ZYT-90/120 series motors.

9. ZYT-90/120 series motor withstand voltage standard; 1500V (50Hz)/5mA/1S, no breakdown.

10. Check whether the appearance of the whole machine has any adverse phenomena such as paint peeling, scratches, and rust.

11. When the carton is tightly sealed, there are defects such as seamlessness, damage, and cracking.

Analysis of common defective products

See the table below for common fault analysis of DC motors

Symptoms

cause

judgment and treatment

motor won't start

1. Open circuit or grounding of armature, excitation winding and connecting wire

1. Use a multimeter to measure the DC resistance of the armature and the excitation winding (it is advisable to check the inter-chip resistance of the armature)

2. Use a megohmmeter to check whether the ground insulation resistance of a conductive part meets the specification requirements, and eliminate it after checking the cause (or repair or replace damaged parts)

2. Poor contact between armature and commutator

1. Use a multimeter or an electric bridge to check whether the resistance of the armature circuit is stable. The instability indicates that the contact between the armature and the commutator is poor, and the armature pressure needs to be adjusted.

2. The coordination between the armature and the brush holder and whether the hole of the brush holder is inclined. If necessary, the spring, brush or brush holder needs to be replaced. After replacing the brushes, make the running-in surface of the brushes and the commutator more than 75% before use to ensure good contact.

3. The excitation winding of the series motor is reversed

1. When the excitation winding is energized, use a small compass to check whether the direction of the minimum magnetic flux is opposite. Otherwise, it means that the excitation winding is reversed. Just swap the two lead wires of the one-pole winding.

The motor speed is too high

1. For permanent magnet DC motors, it may be due to the strong overload of the motor or the existence of a strong external magnetic field around the stator, which may cause the stator permanent magnet to lose its magnetism (or the permanent magnet itself has a small magnetic flux)

1. It is necessary to re-magnetize the permanent magnet, and check the characteristics of the motor after magnetization

2. For electromagnetic DC motors, the short circuit or grounding of the excitation winding will lead to the reduction of the air gap flux of the motor

1. Only need to use a multimeter to check the DC resistance of the excitation winding, and use a megohmmeter to check whether the insulation resistance of the excitation winding to the ground meets the regulations, otherwise the excitation winding and the corresponding insulating structural parts should be replaced.

3. The position of the brush is incorrect or the welding position of the lead wire of the brush element to the commutator piece on the commutator is incorrect

Motor speed is too low

1. The armature winding components have short circuit and open circuit phenomenon

2. There is a short circuit and grounding phenomenon between the commutator segments of the commutator

3. The position of the brush is incorrect or the welding position of the lead wire of the brush element to the commutator piece on the commutator is incorrect

The brush sparks are large, and the commutator and point brushes are seriously heated

1. Due to the surface oxidation of the commutator, the contact between the brush and the commutator is poor

1. The simple improvement method is to polish the surface of the commutator with fine sandpaper, remove the oxide layer and other dirt, and improve the contact performance

2. Add a suitable capacitor (250V/684J CBB capacitor) to reduce sparks (such as ZYT-13X series anti-SME interference)

2. Because the insulating layer (or mica or plastic) between the commutator slices is not well engraved, the commutator surface is not smooth due to the part exceeding the height of the commutator slices

3. The position of the brush box is incorrect due to the looseness of the brush box

Just correct the position of the brush box and retighten it

4. Improper brush pressure

The brush pressure needs to be adjusted. For micro DC motors, the general brush pressure should be 4.9-19.6KPa (50-200g/ cm² )

5. It is caused by faults such as armature winding short circuit, open circuit, grounding or reverse connection.

6. The excitation winding of the series-excited DC motor is grounded or short-circuited.

7. The welding position of the lead wire of the armature winding component to the commutator is wrong

Need to move to the brush position to achieve the elimination of sparks or minimal sparks

8. Wrong hanging of armature winding components

9. Caused by short circuit or grounding between commutation pieces

Check and remove the copper powder in the mica groove of the commutator

Increased brush sparks when the motor rotates in reverse

1. The position of the brush is incorrect

Need to move to the brush position to achieve the elimination of sparks or minimal sparks

2. The welding position of the lead wire of the armature winding component to the commutator is wrong

Motor overheats (burns out)

1. Overload

If the load is correct, check the coupling structure between the motor and the load

2. The motor exceeds the maximum speed

Recheck the rated maximum speed of the motor

3. High ambient temperature

Recheck the rated ambient temperature of the motor and improve ventilation conditions

4. Bearing wear

replace the bearing

5. Armature winding short circuit

Repair or replace the armature

6. The armature rubs against the stator

Check the cause of the friction, eliminate the fault, and replace the stator or armature

The no-load starting current is too large

1. Bearing wear

replace the bearing

2. The brush is worn or stuck

Check brush holders, troubleshoot or replace brushes

3. Magnetic field demagnetization

permanent magnet recharging

4. The armature rubs against the stator

Check the cause of the friction and eliminate the fault

5. The preload on the bearing is too large

Eliminate overload

6. The bearing is different from the shaft (shaft bending)

Make the brushes straight before reassembling

opposite direction of rotation

1. The lead wires of the motor and the power supply are reversely connected

switch wiring

2. Magnetic polarity reversed

Rotate brush position

3. The polarity of the stator magnetic steel is sticky and reversed

4. The brush is installed incorrectly

Turn the housing position

Unstable speed

1. Load change

reload

2. The brush is worn or stuck

Replace brushes, check brush holder faults

3. Foreign matter in the air gap of the motor

Exclude foreign matter

4. Bearing wear

replace the bearing

5. Open circuit, short circuit or poor contact of armature winding

Repair or replace the armature

Brushes wear out quickly

1. Improper selection of brushes

1. Metal-based brushes have low resistivity and contact pressure drop, and are used for low-voltage and high-current motors (such as ZYT-13X series, ZC-10K series series motors)

2. Graphite-based brushes are often used to commutate normal motors (such as ZYT-90/120 series motors)

2. Inappropriate spring pressure

Adjust brush pressure

3. The commutator is rough or dirty

Rework commutator or clean

4. The brush is off-center

Adjust brush position

5. Overload

adjust load

6. Armature winding short circuit

Repair or replace the armature

7. The brush assembly is loose

Adjust the size of brushes and brush holders to make them fit properly

8. Vibration

The armature should be dynamically balanced, and the vibration will cause the brush to jump and produce sparks or excessive wear

9. Humidity difference

Working under near-vacuum conditions will accelerate brush wear, use special wetted or "high-altitude" brushes

Fast bearing wear

1. The shaft coupling or drive gear is not in the same axis, the coupling is unbalanced or the gear mesh is too tight, so that the radial load is too large

Correct the mechanical conditions and limit the radial load below the required value

2. The bearing is dirty

Clean the bearings or replace the bearings, use dust-proof bearings

3. Insufficient or insufficient bearing lubrication

improve lubrication

4. Excessive axial load

Adjustment to reduce axial load

5. The bending of the output shaft causes large vibration

Check shaft runout, straighten or replace armature

Loud noise (axle noise)

1. Unbalanced armature

Armature Calibration Balance

2. Bearing wear or bearing crushing

replace the bearing

3. Large axial clearance

Adjust the axial clearance to the required value

4. The motor and the load are not in the same axis

Improve concentricity

5. The installation of the motor is not fastened

Adjust installation and ensure fastening

6. There is sludge and dust in the air gap of the motor

The noise is irregular, intermittent, and scratching, clean the motor air gap

7. The motor is installed improperly and the noise is amplified

Rubber pad installation is adopted to reduce noise amplification

8. The reversing surface of the commutator is rough

Refinish the commutator

Large radial clearance

1. Loose fit between shaft and bearing

Shaft and bearing fit should be light press fit

2. Loose fit between the bearing and the bearing chamber

The bearing and the bearing chamber should slide freely, the gap should not be too large, and the end cover should be replaced if it is too large

3. Bearing wear

replace the bearing

Large axial clearance

1. The adjustment washer is not suitable

Add an adjusting washer to make the axial clearance meet the requirement

big vibration

1. Unbalanced armature

Armature dynamic balance meets proper requirements

2. Bearing wear

replace the bearing

3. Large radial clearance

Check the cause of the large radial clearance and repair it symptomatically

4. Open circuit or short circuit of armature winding

Repair or replace the armature

The shaft does not turn or the rotation is not flexible

1. No input voltage

Check for voltage at motor input

2. The bearing is tight or stuck

Repair or replace bearings

3. Load failure

Disconnect the motor from the load and see if the motor can rotate. If it can rotate, it is a load problem. Eliminate the failure of the load to rotate

4. Foreign matter in the air gap

Re-repair, remove foreign matter

5. The load is too large

adjust load

6. Open circuit of armature winding

Repair or replace the armature

7. The brush is worn or stuck

Clean the brushes and brush holders