Fresh Garlic has been used as both food and medicine for thousands of years. Fresh garlic contains many nutrients, including phosphorus, potassium, calcium, protein and vitamins B and C. Try to use it on a daily basis to achieve the greatest health benefits.
For fresh garlic ,there are two varieties of garlic: one is Normal White Garlic (with some purple stripes on the skin of the bulbs) and another variety called Pure White Garlic (or snow White Garlic) which does not have any purple stripes on the skin.
Fresh Garlic Fresh Garlic,Fresh White Garlic,Preserving Garlic,Natural Garlic JINING FORICH FRUITS & VEGETABLES CO., LTD. , https://www.forichgarlic.com
First, common faults and maintenance 1. Mechanical oscillation (when acceleration/deceleration)
Common causes of such failures are: 1 pulse encoder failure. At this time, check whether the voltage on the feedback line terminal of the speed detecting unit drops at a certain voltage. If there is a drop indicating that the pulse encoder is defective, replace the encoder; 2 The pulse encoder cross joint may be damaged, resulting in shaft speed and detection. The speed reached is not synchronized, the coupling is replaced; 3 the tachogenerator fails. Repair and replace the speedometer. In the maintenance practice, the speed measuring electromechanical brush wears and the jamming fault is more. At this time, the brush of the speed measuring machine should be removed, and the sandpaper should be sanded a few times, and the dirt of the commutator should be cleaned and reinstalled.
2. Mechanical motion is abnormally fast (speeding)
Such faults should be checked at the same time as the position control unit and the speed control unit. 1) Whether the pulse encoder wiring is wrong; 2) The pulse encoder coupling is damaged; 3 Check whether the tachogenerator terminals are connected and excited. Is the signal line connected incorrectly.
3. If the spindle cannot be moved in a direction or the orientation is not in place, check the adjustment of the orientation control circuit, check the orientation plate, and adjust the spindle control printed circuit board. Also check whether the output waveform of the position detector (encoder) is Normally judge the quality of the encoder (should note that the normal output waveform of the encoder is recorded when the device is normal, so that it can be checked when the fault occurs).
4. Vibration during axis feed Check the motor coil, mechanical feed screw and motor connection, servo system, pulse encoder, coupling, and tachometer.
5. NC error alarm NC alarm is caused by a program error or an operation error. For example, the FAC of FANUC6ME system has 090.091 alarm, the reason may be: 1 main circuit failure and feed rate is too low; 2 pulse encoder is bad; 3 pulse encoder power supply voltage is too low (at this time adjust the power supply 15V voltage, make the main circuit The voltage value on the +5V terminal of the board is within 4.95-5.10V); 4 there is no one-turn signal input to the pulse encoder and the reference point return cannot be performed normally.
6 Servo system alarm servo system failure often occurs the following alarm numbers, such as FANUC 6ME system 416, 426, 436, 446, 456 servo alarm; STEMENS 880 system 1364 servo alarm; STEEMENS 8 system 114, 104 and other servo alarm, At this time, it should be checked: the 1-axis pulse encoder feedback signal is disconnected, short-circuited and lost, and the A and B-phase one-turn signals are measured by the ferry to see if it is normal; 2 the internal fault of the encoder causes the signal to be received incorrectly. Check that it is contaminated, dirty, deformed, etc.
Second, the fault example Example l fault phenomenon: CNC 862 system 20 lathe, X-direction cutting parts when the dimensional error is 0.32mm / 250mm, CRT no alarm display.
Fault analysis: The X and Z axes of the machine tool are driven by the servo unit to control the DC servo motor, and the photoelectric pulse encoder is the position detection. The reasons for the processing size error are: 1X to the ball screw and the silk mother pair have a relatively large gap or The bearing connected to the motor and the lead screw is damaged, resulting in an error in the actual stroke and the detected size; 2 the measurement circuit is defective.
Trouble-shooting: After checking the gap between the lead screw and the nut, the bearing has no bad phenomenon. The cable connection and connector of the measuring circuit are good. Check the signal of the encoder with an oscilloscope, and the waveform is not normal. Remove the encoder and find that the opaque part of the photoelectric disk does not know what causes three transparent dots, causing errors in the detection signal. Replace the encoder and solve the problem. Because the self-diagnosis function of the CNC 862 system is not particularly strong, when such a fault occurs, the machine does not stop and there is no NC alarm display.
Example 2 Fault phenomenon: FANUC 6ME system double-sided machining center, vibration occurs during X-direction movement, and NC416 alarm occurs in CRT.
Fault analysis: The cause of the fault may be 1 speed control unit failure; 2 position detection circuit is bad; 3 pulse encoder feedback cable and connection is bad; 4 pulse encoder is bad; 5 servo motor and tachometer fault; 6 machine data is not correct.
Troubleshooting: Check the speed control unit, main circuit board, pulse encoder feedback cable and connection, machine data are normal, then disconnect the motor from the mechanical part, turn the motor by hand, observe the diagnostic status of No. 713 (713 diagnostic content is: 713.3～713.O are the X-axis pulse encoder feedback signal, feedback one-turn signal, B-phase feedback signal, and A-phase feedback signal. If the pulse encoder is disconnected, 713.3 is 1, 713.2, 713.1, 713.0 normal motor rotation Should be "0", "1" constantly changing), found that the 713.0 signal is only "0" unchanged "1", using the oscilloscope to detect the A, B phase and one turn signal of the pulse encoder, found that the A phase signal is not normal, It can be judged that the pulse encoder is defective, the new encoder is replaced, and the fault is solved.
Example 3 Fault phenomenon: A SIEMENS 880 horizontal machining center workbench has a fault during the rotary positioning process, and the operation is interrupted. The CRT has a 1364 alarm number, and the content is 1364 ORD 4B2 Measuing System Dirty, that is, the measurement system is contaminated.
Trouble-shooting: first remove the detection circuit board and feedback cable connector, clean the dust and oil with alcohol, start the workbench, the fault remains, and remove the pulse encoder that detects the position of the workbench. It is found that it is full of mechanical oil, because The compressed air used to blow out the encoder dust is unclean, and the mechanical oil enters the encoder with the compressed air. Clean the oil with gasoline and improve the quality of the compressed air. After reinstalling the encoder, start the workbench and eliminate the fault.
Example 4 Fault phenomenon: SIEMENS 8 system horizontal machining center, the machine tool suddenly stops running during processing, the NCRT alarm occurs in the CRT, the power supply is restarted, the alarm is eliminated, and the machine tool returns to normal. However, the above fault occurs after working, and so on.
Fault analysis: Query NC 104 alarm, the content is X-axis measurement closed-loop cable break short circuit, signal loss, incorrect threshold signal, frequency signal. The X, Y and Z axes of the machine tool use the grating ruler to detect the position of the machine tool and perform feedback control to form a closed loop system.
Trouble-shooting: Check the reading head and the grating scale. The grating ruler is well sealed. It is not contaminated by oil and dust, and the reading head and the grating ruler are normal. Check the differential amplifier and the measuring circuit board. No bad phenomena are found. The feedback terminal is measured. It was found that the voltage of line 13 was unstable. After the power failure, the line was measured and found to have a large resistance. After investigation, it was found that the line would be broken in the X-direction moving along with the guide rail, which seemed to be connected, causing the feedback value to be unstable and deviating. The actual value causes the motor to lose its step. After the disconnection is processed, the machine is started and the fault is eliminated.
Third, maintenance (1) The power supply voltage must be rated, the working environment temperature can not exceed the standard, in order to facilitate the normal operation of the system's integrated circuits, electronic components.
(2) Avoid strong vibration and friction to prevent damage to the code board, and avoid contamination by dust and oil, so as not to affect the output of normal signals.
(3) Avoid external power supply and noise interference, and ensure good shielding to avoid affecting the feedback signal.
(4) Ensure that the feedback capacity of the feedback cable is normal to ensure the transmission of normal signals.
(5) The components should be installed correctly. For example, the encoder coupling shaft should be aligned concentrically to prevent the shaft from exceeding the allowable load capacity to ensure its normal performance.
Common faults and repairs of detection devices in servo systems
The detection device is an important part of the CNC machine tool servo system. It is used to detect the displacement and speed of each control axis. In actual use, due to wear and pollution, the detection device failure often occurs, causing the servo system to fail to drive the machine to operate normally.