GB/T 15857-1995 General technical requirements for audio-controlled heads of VHS video recorders
Some standard content:
ICS33.160.40
National Standard of the People's Republic of China
GB/T15857—1995
General specification for audio/controlheads of VHS video tape recordersPromulgated on December 22, 1995
State Administration of Technical Supervision
Implementation on August 1, 1996
National Standard of the People's Republic of China
General specification for audio/controlheads of VHS video tape recorders1 Subject content and scope of application
GB/T15857—1995
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, transportation and storage requirements for audio/controlheads of VHS video tape recorders.
This standard applies to fixed audio control heads for VHS video tape recorders with 50 fields/625 lines television format. 2 Reference standards
Packaging, storage and transportation pictorial marking
Batch inspection, counting sampling procedures and sampling tables (applicable to the inspection of continuous batches) GB2828
GB2829
GB4013
GB7399
Periodic inspection, counting sampling procedures and sampling tables (applicable to the inspection of the stability of the production process) Audio and video terminology
VHS type 12.65mm spiral scanning cassette tape video system Cassette tape recorder head general technical conditions GB8494.1
GB/T14306 Cassette video tape
3 Terms
3.1 Audio control head audio/controlhead The head that integrates the audio recording and playback head (or playback head), the mute head and the control head is called an audio control head. It is referred to as an audio control head. 3.2 Other terms used in this standard comply with the provisions of GB4013. 4 Technical requirements
4.1 Conditions of use
Ambient temperature: -5～55℃;
Relative humidity: 40%~80%,
Atmospheric pressure: 86~106kPa.
4.2 Appearance and structural requirements
4.2.1 The contact part between the head and the tape should be smooth, without pinholes and scratches. The roughness of the working surface of the head should meet the requirements of Figure 1. 4.2.2 The appearance of the head should be smooth and flat, without obvious mechanical damage, deformation, cracks, burrs and rust. The potting glue should be full and moderate, without obvious bubbles. The lead pins should be straight and firm, with good solderability. 4.2.3 The markings should be clear and firm.
4.2.4 The connection between the mounting plate and the head body should be able to withstand a pulling force of 25N (2.5kgf) without falling off. Approved by the State Bureau of Technical Supervision on December 22, 1995 and implemented on August 1, 1996
4.3 Relevant dimensions
GB/T15857—1995
The relevant dimensions of the single-track head and the dual-track head shall meet the requirements of Figures 2 and 3 respectively. 90*0+0
4.4 Basic parameters
BO-TO'
4.4.1 The basic parameters of the audio recording and playback head shall meet the requirements of Table 1. Table 1
Basic parameters
Rated values
Measurement conditions
1kHz,100mA
Basic parameters
Bias frequency
Bias current
Recording and playback sensitivity
Recording and playback sensitivity Channel difference
Recording and playback frequency response
Recording and playback frequency response Channel difference
Recording and playback distortion
Insulation resistance
GB/T15857—1995
Continued Table 1
Specified by product standards
Specified by product standards
-68±3
—5±3
The basic parameters of the mute head shall comply with the provisions of Table 2. Table 2
Basic parameters
Muffle current
Muffle effect
Basic parameters of the control head should comply with the provisions of Table 3. Table 3
Basic parameters
Write current
Read voltage
—72±3
Specified by product standards
Specified by product standards
Specified by product standards
When the control signal is positive, the magnetic pole on the side of the control head close to the magnetic drum should be the N pole. 4.5 Environmental adaptability requirements
Measurement conditions
8kHz/1kHz
Third harmonic distortion
DC250V
Measurement conditions
1kHz saturation recording
Belt speed 23.39mm/s
Measurement conditions
25Hz square wave (peak-to-peak)
4.5.1 The appearance and basic parameters of the test samples shall be measured before the environmental test, and shall meet the corresponding provisions of Articles 4.2 and 4.4. The main performance parameters and requirements detected after the test shall be in accordance with the provisions of Table 4. Table 4
Recording and playback sensitivity
Recording and playback frequency response
Recording and playback distortion
Noise elimination effect
Initial value±20%
Initial value±3dB
Initial value aB
Conforms to the provisions of Table 1
Conforms to the provisions of Table 1
4.5.2 The magnetic head is placed at a temperature of 70℃ for 48 hours. After recovery, its main performance parameters shall conform to the provisions of Table 4. 4.5.3 After the magnetic head is placed at a temperature of 40℃ and a relative humidity of 93% for 48 hours, the insulation resistance is measured in the box. The value shall be greater than or equal to 1MQ. After recovery, its main performance parameters shall conform to the provisions of Table 4. 4.5.4 The magnetic head is placed at a temperature of -25℃ for 24 hours. After recovery, its main performance parameters shall conform to the provisions of Table 4. 3
GB/T15857—1995
4.5.5 After the magnetic head is subjected to the temperature test of 70～－25℃ for five cycles as shown in Figure 4, its main performance parameters shall meet the requirements of Table 4 after recovery.
t, nain
After the magnetic head is subjected to the vibration test as specified in Table 5, its main performance parameters shall meet the requirements of Table 4. 4.5.6
Frequency range
10~30~10
30~55~30
Displacement amplitude
On each axis
Sweep frequency cycles
Vibrate in three mutually perpendicular axes in sequence according to the working position
4.5.7After the magnetic head is subjected to 1000 impact tests with an acceleration of 250m/s2 and a pulse duration of 6ms, its main performance parameters shall comply with the provisions of Table 4.
4.5.8After the small packaged magnetic head is subjected to a drop test at a height of 1m, twice on the front, back and side surfaces, its main performance parameters shall comply with the provisions of Table 4.
4.6Life requirements
The life of the voice-controlled magnetic head shall be greater than or equal to 2000h. 5 Test method
5.1 Measurement conditions
Temperature: 15~35℃,
Relative humidity: 45%~75%
Atmospheric pressure: 86~106kPa.
5.2 Test equipment
5.2.1 Measurement video recorder
Tape speed: 23.39mm/s, tolerance 0.2%
Wow and flutter rate: ≤0.2%
Other performances shall comply with the requirements of GB7399. 5.2.2 Test tape
The test tape shall comply with the provisions of the superior tape of GB/T14306; a.
b. Audio playback azimuth calibration tape: 10kHz, -10dB. 5.2.3 Arm length comparison instrument
Magnification: 30;
Accuracy: 0.01mm.
5.2.4 Interference microscope
GB/T15857—1995
Measurement surface profile micro-roughness range: 1～0.03μm. 5.2.5 Audio signal generator
Frequency range: 20Hz~20kHz;
Amplitude error: ±0.5dB;
Frequency error: ±2%;
Harmonic distortion: 0.1%;
Output impedance: ≤6002.
5.2.6 Broadband signal generator
Frequency range: 20Hz~200kHz;
Amplitude error: ±1dB;
Frequency error: ±2%
Harmonic distortion: ≤0.5%
Output impedance: 600Q5k2;
Output power:>5W.
5.2.7 Measurement amplifier
Maximum gain: ≥60dB;
Measurement range: 10μV~30mV (full scale); Frequency response: 20Hz~20kHz, ±0.5dB; Harmonic distortion: <0.2% (250Hz~2kHz) ≤0.5% (other frequencies)
Signal-to-noise ratio:>60dB (when the input voltage is 1mV and the source impedance is a well-shielded 600Q) Input impedance: ≥500k,
Input capacitance: <30pF.
5.2.8 Bandpass filter
Center frequency: 315Hz, 1kHz;
Selectivity: attenuation of more than 30dB from the center frequency to 1oct; signal-to-noise ratio: ≥60dB (input voltage is 1mV). 5.2.9 Millivoltmeter
Measurement range: 1~30V (full scale);
Frequency range: 20Hz~200kHz;
Measurement error: ±3%;
Input resistance: ≥500k2;
Input capacitance: <30pF.
5.2.10 TV signal generator
Output signal amplitude: 0~2.0V (peak-to-peak) adjustable; output impedance: 75Q;
TV standard: PAL.
5.2.11 Image monitor
Horizontal resolution: greater than 500 lines.
5.2.12 Dual-trace oscilloscope
Vertical sensitivity: 1mV (peak-to-peak); frequency range: 0~20MHz;
Rise time: ≤10μs.
5.2.13 Distortion meter
Measurement range: 0.1%~10%,
Frequency range: 20Hz~20kHz;
Accuracy: ±5%;
Input voltage: <100mV (full scale);
Input resistance: >500kg;
Input capacitance: <300pF.
5.2.14 Impedance tester
10~5000Q,1kHz.
5.2.15 Megaohmmeter
250V.
5.2.16 Tension gauge
Maximum tension:>98.1N(10kgf).
5.3 Appearance, structure and related dimensions inspection
GB/T15857—1995
5.3.1 Check the appearance of the magnetic head by visual inspection or low-power magnifying glass. 5.3.2 Measure the roughness of the working surface of the magnetic head by interference microscope or roughness sample block. 5.3.3 Test the lead pins by visual inspection or tweezers. Its solderability is tested by the following soldering method: When the soldering iron temperature rises to 350℃, use 3.8mm rosin core solder wire to contact the lead end of the magnetic head with the lead for less than 3s, and it should be able to be soldered firmly.
5.3.4 Use a tensile force gauge to measure the connection strength between the mounting plate and the head body. 5.3.5 Use an arm length ratio meter to measure the relevant dimensions of the head. 5.4 Basic parameter measurement
5.4.1 Measurement preparation
a. Clean the surface of the head and demagnetize the head and other parts in contact with the tape; b. Replay the "azimuth" calibration tape and adjust the azimuth of the playback head or recording head to maximize its output. 5.4.2 Impedance
Use an impedance tester to measure the impedance at both ends of the head coil. 5.4.3 Recording and playback sensitivity
Selection of the best bias current: Recording is performed with the reference tape at a rated recording current of 6.3kHz and the bias current superimposed. When the bias current increases, the output level shown in Figure 5 is obtained. The bias current that drops 5dB after reaching the maximum output is the best output current.
Use the best bias current and the specified recording current to record at the reference frequency. Play back the recorded signal, and its output level is the recording and playback sensitivity.
5.4.4 Recording and playback frequency response
Cat, cIB
Measure the recording and playback sensitivity according to 5.4.3;
GB/T15857—1995
Wang's abuse point
Adjust the recording current of the reference frequency so that the recording level is 10dB lower than the reference level. Keep the input level unchanged, and then record the test frequency signal; replay the above recorded signal, with the output of the reference frequency as 0dB, and the output level of the test frequency is the recording and playback frequency response. c. 5.4.5 The block diagram of the measurement of the recording and playback sensitivity and the inter-channel difference of the recording and playback frequency response is shown in Figure 6; measure the difference of the recording and playback sensitivity of the two channels according to 5.4.3, expressed in decibels, b. measure the difference of the recording and playback frequency response of the two channels according to 5.4.4, expressed in decibels. gobZxz.net
no electric group
see the letter music
version of the sound
display
lost the classic classic fake
rely on the fast meter
in the figure: L, C1's filtering effect should be greater than 30dB, R, should make the recording current constant. 5.4.6 Recording and playback distortion
Haishen Ship
Nuankong
Beijing Boots
Use a reference tape to record at the reference frequency to reach the reference magnetic level. Replay the recorded signal and measure the third harmonic distortion of the reference frequency. 5.4.7 Insulation resistance
Use a megohmmeter to measure the resistance between the grounding point of the magnetic head and the lead end. 7
5.4.8 Elimination effect
GB/T15857—1995
The measurement block diagram is shown in 7. Use a reference tape to record at the reference frequency to reach the saturation magnetic level; use the measured eliminator to partially demagnetize the above-mentioned recorded magnetic tape, b.
Measure the difference in output level between the un-eliminated part and the erased part through a bandpass filter. o,o
micrometer
no electric limit
In the figure: L, Ci, R, the requirements are the same as those in Figure 6. 5.4.9 Write current
Frequency monitor
Electrical meter
Generator
Frequency signal
Electronic case clothing
Realizer
Family filling narrow
Signal symbiosis
Electrical meter
Measurement block diagram is shown in Figure 8. Use the control head to record the 25Hz square wave output by the test video recorder, connect a 10Q resistor to the other pole of the control head, and use an oscilloscope to measure the square wave amplitude on the resistor divided by 10Q to get the write current. YTR
Borrowed optical instrument
5.4.10 Reading voltage
Visual communication
Xi Sanbu
Teaching information
Prompt statement instrument
Display instrument
Replay the recorded tape of 5.4.9, and use an oscilloscope to measure the output signal amplitude at the output end of the control head. The oscilloscope is triggered by the video head switch signal of the measuring video recorder.
5.4.11 Control head polarity
GB/T15857—1995
Use a magnetic needle or oscilloscope to detect the control head polarity. 5.5 Environmental test method
5.5.1 Test sequence
a. The environmental test is carried out in series, and the test sequence is in the order of sequence arranged in this standard, b. When the production batch is large, it is allowed to conduct environmental tests according to the parallel test scheme specified in Appendix A (Supplement). When there is a dispute, arbitration shall be conducted according to the series test.
5.5.2 High temperature storage test
Put the test sample in a high temperature box and gradually increase the box temperature to 70±2℃ at an average rate of 0.71℃/min. After the sample reaches temperature stability, leave it for 48 hours, then reduce the box temperature to normal test atmospheric conditions at an average rate of 0.71℃/min. After recovery for 2 hours, test according to the provisions of Article 4.5.1.
5.5.3 Constant humidity test
Put the sample in a humidity box and gradually increase the box temperature to 40±2℃. After the sample reaches temperature stability, humidify it to a relative humidity of (93)% and measure the insulation resistance in the box after leaving it for 48 hours. Then, the relative humidity in the test box is reduced to (75 ± 3)% within 0.5h, and then the temperature and humidity of the test box are adjusted to normal test atmospheric conditions within 0.5h. After 2h of recovery, the test is carried out in accordance with the provisions of Article 4.5.1. 5.5.4 Low temperature storage test
Put the test sample in a low temperature box, and reduce the box temperature to -25 ± 3℃ at an average rate of 0.71℃/min. After the sample reaches temperature stability, let it stand for 24h. Then, the box temperature is raised to normal test atmospheric conditions at an average rate of 0.7~1℃/min. After 2h of recovery, the test is carried out in accordance with the provisions of Article 4.5.1.
5.5.5 Temperature cycle test
Place the test sample in a high and low temperature box and perform a temperature cycle test according to the requirements of Figure 4, repeat five times, and allow the sample to recover under normal test atmospheric conditions for 2 hours, and then test according to the provisions of Article 4.5.1. 5.5.6 Sweep frequency vibration test
a. Fasten the test sample on the test bench in the working position and place it in the center area of the platform; b. Perform a sweep frequency vibration of 10~30~10Hz and 30~55~30Hz according to the provisions of Table 5. At a sweep frequency rate of 1oct/min, the time for a cyclic sweep frequency (f1~f2~f1) within a certain frequency range is shown in formula (1): T=6.644 1g (f
Where: T—time, min,
fi——lower limit frequency of sweep frequency, Hz;
f2—upper limit frequency of sweep frequency, Hz.
c. After the test, test according to the provisions of Article 4.5.1. 5.5.7 Impact test
According to the requirements of Article 4.5.7, six samples are tested separately in the three mutually perpendicular axis directions of the test samples. After each sample is subjected to 1000 impact tests in one direction, it is tested according to the provisions of Article 4.5.1. 5.5.8 Drop test
Make the test samples in the small packaging box evenly distributed, and fill the other empty spaces with non-test samples. Place the test samples in the front, back and side of the packaging box in turn. Lift to the specified height, with the test surface parallel to the ground. Release suddenly while ensuring that the initial velocity in all directions is zero, allowing the test sample to fall freely onto the flat cement floor. Repeat the fall twice on each side. After the test, inspect according to the provisions of Article 4.5.1. 5.6 Life test method
The life test method of the voice-controlled magnetic head is to be determined.
6 Inspection rules
6.1 Inspection classification
GB/T15857—1995
Product inspection is divided into finalization inspection, delivery inspection and routine inspection. 6.2 Finalization inspection
Products should be subject to finalization inspection during design and production finalization. 6.2.1 Inspection items
Finalization inspection shall be in accordance with the provisions of Articles 4.2 to 4.6 6.2.2 Sample extraction
The batch of finalized production shall be no less than 10,000, and the number of samples shall be greater than 100. The number of samples for design finalization can be less than that for production finalization. Samples shall be randomly selected from the finalized batch products. The number of samples for each group of tests is shown in Table 6. Table 6
6.2.3 Processing of inspection results
Appearance, structure and related dimensions
Basic parameters
Environmental test
Life test
If all tests of each group of samples are qualified, the number of qualified samples for type inspection shall be determined
For items that fail in finalization inspection, the reasons shall be found out, and after taking improvement measures, the item shall be re-inspected until it passes. 6.3 Acceptance inspection Inspection
After the production is finalized and the production is stable, the continuous batches of products that have passed the inspection by the production unit shall be subject to delivery inspection. 6.3.1 Inspection items
The delivery inspection items include the parameters specified in Articles 4.2 and 4.4. 6.3.2 Sampling plan
The delivery inspection adopts the normal inspection one-time sampling plan in GB2828. The inspection level and qualified quality level shall be in accordance with the provisions of Table 7. Table 7
Inspection level
6.3.3 Product submission
Qualified quality level AQL
The size of the product submission batch is determined by the manufacturer. Generally, the same model of products produced in the same batch (when the quality of materials and parts and the process flow remain unchanged) shall be submitted as a batch. 6.3.4 Sample extraction
Based on the size of the batch submitted for inspection, the sample size shall be determined according to the inspection level specified in Table 7, and random sampling shall be conducted in the batch of products. 6.3.5 Qualification judgment
When the samples of the delivery inspection meet the requirements of Article 6.3.2, the quality of the submitted batch is judged to be qualified, otherwise it is unqualified; a.
The products judged to be unqualified shall be repaired or sorted according to the unqualified items. After the unqualified products are removed, they can be submitted for inspection again. 6.3.6 Strict and relaxed inspection
The delivery inspection specified in this standard generally adopts normal inspection. When the normal inspection conditions are not met, strict inspection should be carried out. When the relaxed inspection conditions are met, relaxed inspection can also be used; b.
The transfer rules of strict and relaxed inspection shall be implemented in accordance with the provisions of GB2828; the sampling plan, inspection level and qualified quality level of strict and relaxed inspection are consistent with normal inspection. 6.4 Routine inspection
GB/T15857-1995
Routine inspection is carried out by the quality inspection department of the manufacturer (or with the participation of users), and is carried out every six months for continuously produced products. When there is a change in the structure, material or manufacturing process of the magnetic head, routine inspection should be carried out. 6.4.1 Inspection Items
Routine inspection shall be carried out on the items specified in Articles 4.2 to 4.5. 6.4.2 Sampling Plan
Routine inspection adopts the secondary sampling plan in GB2829, and the discrimination level and unqualified quality level (RQL) shall be in accordance with the provisions of Table 8. Table 8
Discrimination Level
6.4.3 Sample Sampling
Sampling Plan
Judgment Array
a. The samples submitted for inspection must be randomly selected from the products produced and put into storage during the same period. For the selected samples, if they are found to be unqualified, they shall be replaced with randomly selected qualified products. At the same time, analyze the unqualified products, find out the reasons, and record them in the routine inspection report, but they are not used as the basis for judging whether the routine inspection is qualified or not.
b. According to the discrimination level, RQL and judgment array specified in Table 8, according to the sample size specified in GB2829, draw samples separately (including samples for secondary sampling) and draw them all at once. 6.4.4 Qualification judgment
If the test samples of routine inspection meet the requirements of Articles 4.2 to 4.5, they are qualified products. If the number of qualified products meets the requirements of Table 8, the routine inspection is judged to be qualified, otherwise it is unqualified; b. If the routine inspection is unqualified, the products produced in this period are judged to be unqualified. Unqualified products shall not be shipped out of the factory and production shall be stopped. Production can only be resumed after the reasons are found and effective measures are taken. For the first batch of products after the resumption of production, routine inspection must be carried out again, and production can only be continued after the inspection is qualified.
Products judged as unqualified must be repaired or screened, and only after passing routine inspection can they be considered qualified. 6.4.5 Handling of inspection results
For products produced during the period that have failed routine inspection and have been shipped, the quality responsibility shall be borne by the manufacturer. The specific handling method shall be negotiated and resolved by the supply and demand parties;
Products that have undergone routine inspection shall not be shipped as genuine products b.
7 Marking, packaging, transportation, storage
7.1 Marking
The model and trademark shall be marked on the finished magnetic head. a.
The marking on the packaging box shall comply with the provisions of GB191. 7.2 Packaging
The inner packaging of the magnetic head shall ensure that the working surface of the magnetic head is not scratched and the magnetic heads do not collide with each other. 7.3 Transportation
The packaged magnetic head can be transported by normal land, sea and air transportation. During transportation, it should be avoided from direct rain and snow or exposure to the sun. 7.4 Storage
The packaged magnetic heads should be stored in a warehouse with a temperature of -15-40℃, a relative humidity of no more than 80%, and no acidic or other harmful gases around. The storage period should not exceed six months. Otherwise, the delivery inspection should be carried out again before leaving the factory, and only qualified ones can leave the factory. 118 Drop test
Make the test samples in the factory small packaging box evenly distributed, and fill the other empty spaces with non-test samples. Lift the test samples to the specified height in the front, back and side of the packaging box in turn, and the test surface is parallel to the ground. While ensuring that the initial velocity in each direction is zero, suddenly release the test sample and let it fall freely on the flat cement floor. Repeat the fall twice on each side. After the test, test it according to the provisions of Article 4.5.1. 5.6 Life test method
The life test method of the voice control head is to be determined.
6 Inspection rules
6.1 Inspection classification
GB/T15857—1995
Product inspection is divided into finalization inspection, delivery inspection and routine inspection. 6.2 Finalization inspection
Products should be subject to finalization inspection when the design is finalized and the production is finalized. 6.2.1 Inspection Items
The finalization inspection shall be conducted on the items specified in 4.2 to 4.6. 6.2.2 Sample Extraction
The batch of finalized production shall be no less than 10,000, and the number of samples shall be greater than 100. The number of samples for design finalization may be less than that for production finalization. Samples shall be randomly extracted from the finalized batch of products. The number of samples for each group of tests is shown in Table 6. Table 6
6.2.3 Processing of Inspection Results
Appearance, Structure and Related Dimensions
Basic Parameters
Environmental Test
Life Test
If all the tests of each group of samples are qualified, the number of qualified samples for type inspection shall be determined
For the items that fail in the finalization inspection, the reasons shall be found out, and after taking improvement measures, the inspection shall be repeated until they are qualified. 6.3 Acceptance inspection
After the production is finalized and the production is stable, the continuous batches of products that have passed the inspection by the production unit shall be subject to acceptance inspection. 6.3.1 Inspection items
The acceptance inspection items include the parameters specified in Articles 4.2 and 4.4. 6.3.2 Sampling plan
The acceptance inspection adopts the normal inspection one-time sampling plan in GB2828. The inspection level and qualified quality level shall be in accordance with the provisions of Table 7. Table 7
Inspection level
6.3.3 Product submission
Qualified quality level AQL
The size of the product submission batch is determined by the manufacturer. Generally, the same model of products produced in the same batch (when the quality of materials and parts and the process flow remain unchanged) shall be submitted as a batch. 6.3.4 Sample extraction
Based on the size of the batch submitted for inspection, the sample size shall be determined according to the inspection level specified in Table 7, and random sampling shall be conducted in the batch of products. 6.3.5 Qualification judgment
When the samples of the delivery inspection meet the requirements of Article 6.3.2, the quality of the submitted batch is judged to be qualified, otherwise it is unqualified; a.
The products judged to be unqualified shall be repaired or sorted according to the unqualified items. After the unqualified products are removed, they can be submitted for inspection again. 6.3.6 Strict and relaxed inspection
The delivery inspection specified in this standard generally adopts normal inspection. When the normal inspection conditions are not met, strict inspection should be carried out. When the relaxed inspection conditions are met, relaxed inspection can also be used; b.
The transfer rules of strict and relaxed inspection shall be implemented in accordance with the provisions of GB2828; the sampling plan, inspection level and qualified quality level of strict and relaxed inspection are consistent with normal inspection. 6.4 Routine inspection
GB/T15857-1995
Routine inspection is carried out by the quality inspection department of the manufacturer (or with the participation of users), and is carried out every six months for continuously produced products. When there is a change in the structure, material or manufacturing process of the magnetic head, routine inspection should be carried out. 6.4.1 Inspection Items
Routine inspection shall be carried out on the items specified in Articles 4.2 to 4.5. 6.4.2 Sampling Plan
Routine inspection adopts the secondary sampling plan in GB2829, and the discrimination level and unqualified quality level (RQL) shall be in accordance with the provisions of Table 8. Table 8
Discrimination Level
6.4.3 Sample Sampling
Sampling Plan
Judgment Array
a. The samples submitted for inspection must be randomly selected from the products produced and put into storage during the same period. For the selected samples, if they are found to be unqualified, they shall be replaced with randomly selected qualified products. At the same time, analyze the unqualified products, find out the reasons, and record them in the routine inspection report, but they are not used as the basis for judging whether the routine inspection is qualified or not.
b. According to the discrimination level, RQL and judgment array specified in Table 8, according to the sample size specified in GB2829, draw samples separately (including samples for secondary sampling) and draw them all at once. 6.4.4 Qualification judgment
If the test samples of routine inspection meet the requirements of Articles 4.2 to 4.5, they are qualified products. If the number of qualified products meets the requirements of Table 8, the routine inspection is judged to be qualified, otherwise it is unqualified; b. If the routine inspection is unqualified, the products produced in this period are judged to be unqualified. Unqualified products shall not be shipped out of the factory and production shall be stopped. Production can only be resumed after the reasons are found and effective measures are taken. For the first batch of products after the resumption of production, routine inspection must be carried out again, and production can only be continued after the inspection is qualified.
Products judged as unqualified must be repaired or screened, and only after passing routine inspection can they be considered qualified. 6.4.5 Handling of inspection results
For products produced during the period that have failed routine inspection and have been shipped, the quality responsibility shall be borne by the manufacturer. The specific handling method shall be negotiated and resolved by the supply and demand parties;
Products that have undergone routine inspection shall not be shipped as genuine products b.
7 Marking, packaging, transportation, storage
7.1 Marking
The model and trademark shall be marked on the finished magnetic head. a.
The marking on the packaging box shall comply with the provisions of GB191. 7.2 Packaging
The inner packaging of the magnetic head shall ensure that the working surface of the magnetic head is not scratched and the magnetic heads do not collide with each other. 7.3 Transportation
The packaged magnetic head can be transported by normal land, sea and air transportation. During transportation, it should be avoided from direct rain and snow or exposure to the sun. 7.4 Storage
The packaged magnetic heads should be stored in a warehouse with a temperature of -15-40℃, a relative humidity of no more than 80%, and no acidic or other harmful gases around. The storage period should not exceed six months. Otherwise, the delivery inspection should be carried out again before leaving the factory, and only qualified ones can leave the factory. 118 Drop test
Make the test samples in the factory small packaging box evenly distributed, and fill the other empty spaces with non-test samples. Lift the test samples to the specified height in the front, back and side of the packaging box in turn, and the test surface is parallel to the ground. While ensuring that the initial velocity in each direction is zero, suddenly release the test sample and let it fall freely on the flat cement floor. Repeat the fall twice on each side. After the test, test it according to the provisions of Article 4.5.1. 5.6 Life test method
The life test method of the voice control head is to be determined.
6 Inspection rules
6.1 Inspection classification
GB/T15857—1995
Product inspection is divided into finalization inspection, delivery inspection and routine inspection. 6.2 Finalization inspection
Products should be subject to finalization inspection when the design is finalized and the production is finalized. 6.2.1 Inspection Items
The finalization inspection shall be conducted on the items specified in 4.2 to 4.6. 6.2.2 Sample Extraction
The batch of finalized production shall be no less than 10,000, and the number of samples shall be greater than 100. The number of samples for design finalization may be less than that for production finalization. Samples shall be randomly extracted from the finalized batch of products. The number of samples for each group of tests is shown in Table 6. Table 6
6.2.3 Processing of Inspection Results
Appearance, Structure and Related Dimensions
Basic Parameters
Environmental Test
Life Test
If all the tests of each group of samples are qualified, the number of qualified samples for type inspection shall be determined
For the items that fail in the finalization inspection, the reasons shall be found out, and after taking improvement measures, the inspection shall be repeated until they are qualified. 6.3 Acceptance inspection
After the production is finalized and the production is stable, the continuous batches of products that have passed the inspection by the production unit shall be subject to acceptance inspection. 6.3.1 Inspection items
The acceptance inspection items include the parameters specified in Articles 4.2 and 4.4. 6.3.2 Sampling plan
The acceptance inspection adopts the normal inspection one-time sampling plan in GB2828. The inspection level and qualified quality level shall be in accordance with the provisions of Table 7. Table 7
Inspection level
6.3.3 Product submission
Qualified quality level AQL
The size of the product submission batch is determined by the manufacturer. Generally, the same model of products produced in the same batch (when the quality of materials and parts and the process flow remain unchanged) shall be submitted as a batch. 6.3.4 Sample extraction
Based on the size of the batch submitted for inspection, the sample size shall be determined according to the inspection level specified in Table 7, and random sampling shall be conducted in the batch of products. 6.3.5 Qualification judgment
When the samples of the delivery inspection meet the requirements of Article 6.3.2, the quality of the submitted batch is judged to be qualified, otherwise it is unqualified; a.
The products judged to be unqualified shall be repaired or sorted according to the unqualified items. After the unqualified products are removed, they can be submitted for inspection again. 6.3.6 Strict and relaxed inspection
The delivery inspection specified in this standard generally adopts normal inspection. When the normal inspection conditions are not met, strict inspection should be carried out. When the relaxed inspection conditions are met, relaxed inspection can also be used; b.
The transfer rules of strict and relaxed inspection shall be implemented in accordance with the provisions of GB2828; the sampling plan, inspection level and qualified quality level of strict and relaxed inspection are consistent with normal inspection. 6.4 Routine inspection
GB/T15857-1995
Routine inspection is carried out by the quality inspection department of the manufacturer (or with the participation of users), and is carried out every six months for continuously produced products. When there is a change in the structure, material or manufacturing process of the magnetic head, routine inspection should be carried out. 6.4.1 Inspection Items
Routine inspection shall be carried out on the items specified in Articles 4.2 to 4.5. 6.4.2 Sampling Plan
Routine inspection adopts the secondary sampling plan in GB2829, and the discrimination level and unqualified quality level (RQL) shall be in accordance with the provisions of Table 8. Table 8
Discrimination Level
6.4.3 Sample Sampling
Sampling Plan
Judgment Array
a. The samples submitted for inspection must be randomly selected from the products produced and put into storage during the same period. For the selected samples, if they are found to be unqualified, they shall be replaced with randomly selected qualified products. At the same time, analyze the unqualified products, find out the reasons, and record them in the routine inspection report, but they are not used as the basis for judging whether the routine inspection is qualified or not.
b. According to the discrimination level, RQL and judgment array specified in Table 8, according to the sample size specified in GB2829, draw samples separately (including samples for secondary sampling) and draw them all at once. 6.4.4 Qualification judgment
If the test samples of routine inspection meet the requirements of Articles 4.2 to 4.5, they are qualified products. If the number of qualified products meets the requirements of Table 8, the routine inspection is judged to be qualified, otherwise it is unqualified; b. If the routine inspection is unqualified, the products produced in this period are judged to be unqualified. Unqualified products shall not be shipped out of the factory and production shall be stopped. Production can only be resumed after the reasons are found and effective measures are taken. For the first batch of products after the resumption of production, routine inspection must be carried out again, and production can only be continued after the inspection is qualified.
Products judged as unqualified must be repaired or screened, and only after passing routine inspection can they be considered qualified. 6.4.5 Handling of inspection results
For products produced during the period that have failed routine inspection and have been shipped, the quality responsibility shall be borne by the manufacturer. The specific handling method shall be negotiated and resolved by the supply and demand parties;
Products that have undergone routine inspection shall not be shipped as genuine products b.
7 Marking, packaging, transportation, storage
7.1 Marking
The model and trademark shall be marked on the finished magnetic head. a.
The marking on the packaging box shall comply with the provisions of GB191. 7.2 Packaging
The inner packaging of the magnetic head shall ensure that the working surface of the magnetic head is not scratched and the magnetic heads do not collide with each other. 7.3 Transportation
The packaged magnetic head can be transported by normal land, sea and air transportation. During transportation, it should be avoided from direct rain and snow or exposure to the sun. 7.4 Storage
The packaged magnetic heads should be stored in a warehouse with a temperature of -15-40℃, a relative humidity of no more than 80%, and no acidic or other harmful gases around. The storage period should not exceed six months. Otherwise, the delivery inspection should be carried out again before leaving the factory, and only qualified ones can leave the factory. 11
Products judged as unqualified shall be repaired or sorted according to the unqualified items. After the unqualified products are removed, they can be submitted for inspection again. 6.3.6 Strict and relaxed inspection
The delivery inspection specified in this standard generally adopts normal inspection. When the normal inspection conditions are not met, strict inspection should be carried out. When the conditions for relaxed inspection are met, relaxed inspection can also be used; b.
The transfer rules of strict and relaxed inspection shall be implemented in accordance with the provisions of GB2828; the sampling plan, inspection level and qualified quality level of strict and relaxed inspection are consistent with normal inspection. 6.4 Routine inspection
GB/T15857—1995
Routine inspection shall be carried out by the quality inspection department of the manufacturer (or with the participation of users), and the products produced continuously shall be carried out every six months. When there is a change in the structure, material or manufacturing process of the magnetic head, routine inspection shall be carried out. 6.4.1 Inspection Items
Routine inspections shall be conducted on all items specified in 4.2 to 4.5. 6.4.2 Sampling Plan
Routine inspections shall adopt the secondary sampling plan in GB2829, and the discrimination level and unqualified quality level (RQL) shall be in accordance with the provisions of Table 8. Table 8
Discrimination Level
6.4.3 Sample Sampling
Sampling Plan
Discrimination Array
a. The samples submitted for inspection must be randomly selected from the products produced and put into storage during the same period. For the selected samples, if they are found to be unqualified, they shall be replaced by randomly selected qualified products. At the same time, analyze the unqualified products, find out the reasons, and record them in the routine inspection report, but they are not used as the basis for judging whether the routine inspection is qualified or not.
b. According to the discrimination level, RQL and judgment array specified in Table 8, according to the sample size specified in GB2829, draw samples separately (including samples for secondary sampling) and draw them all at once. 6.4.4 Qualification judgment
If the test samples of routine inspection meet the requirements of Articles 4.2 to 4.5, they are qualified products. If the number of qualified products meets the requirements of Table 8, the routine inspection is judged to be qualified, otherwise it is unqualified; b. If the routine inspection is unqualified, the products produced in this period are judged to be unqualified. Unqualified products shall not be shipped out of the factory and production shall be stopped. Production can only be resumed after the reasons are found and effective measures are taken. For the first batch of products after the resumption of production, routine inspection must be carried out again, and production can only be continued after the inspection is qualified.
Products judged as unqualified must be repaired or screened, and only after passing routine inspection can they be considered qualified. 6.4.5 Handling of inspection results
For products produced during the period that have failed routine inspection and have been shipped, the quality responsibility shall be borne by the manufacturer. The specific handling method shall be negotiated and resolved by the supply and demand parties;
Products that have undergone routine inspection shall not be shipped as genuine products b.
7 Marking, packaging, transportation, storage
7.1 Marking
The model and trademark shall be marked on the finished magnetic head. a.
The marking on the packaging box shall comply with the provisions of GB191. 7.2 Packaging
The inner packaging of the magnetic head shall ensure that the working surface of the magnetic head is not scratched and the magnetic heads do not collide with each other. 7.3 Transportation
The packaged magnetic head can be transported by normal land, sea and air transportation. During transportation, it should be avoided from direct rain and snow or exposure to the sun. 7.4 Storage
The packaged magnetic heads should be stored in a warehouse with a temperature of -15-40℃, a relative humidity of no more than 80%, and no acidic or other harmful gases around. The storage period should not exceed six months. Otherwise, the delivery inspection should be carried out again before leaving the factory, and only qualified ones can leave the factory. 11
Products judged as unqualified shall be repaired or sorted according to the unqualified items. After the unqualified products are removed, they can be submitted for inspection again. 6.3.6 Strict and relaxed inspection
The delivery inspection specified in this standard generally adopts normal inspection. When the normal inspection conditions are not met, strict inspection should be carried out. When the conditions for relaxed inspection are met, relaxed inspection can also be used; b.
The transfer rules of strict and relaxed inspection shall be implemented in accordance with the provisions of GB2828; the sampling plan, inspection level and qualified quality level of strict and relaxed inspection are consistent with normal inspection. 6.4 Routine inspection
GB/T15857—1995
Routine inspection shall be carried out by the quality inspection department of the manufacturer (or with the participation of users), and the products produced continuously shall be carried out every six months. When there is a change in the structure, material or manufacturing process of the magnetic head, routine inspection shall be carried out. 6.4.1 Inspection Items
Routine inspections shall be conducted on all items specified in 4.2 to 4.5. 6.4.2 Sampling Plan
Routine inspections shall adopt the secondary sampling plan in GB2829, and the discrimination level and unqualified quality level (RQL) shall be in accordance with the provisions of Table 8. Table 8
Discrimination Level
6.4.3 Sample Sampling
Sampling Plan
Discrimination Array
a. The samples submitted for inspection must be randomly selected from the products produced and put into storage during the same period. For the selected samples, if they are found to be unqualified, they shall be replaced by randomly selected qualified products. At the same time, analyze the unqualified products, find out the reasons, and record them in the routine inspection report, but they are not used as the basis for judging whether the routine inspection is qualified or not.
b. According to the discrimination level, RQL and judgment array specified in Table 8, according to the sample size specified in GB2829, draw samples separately (including samples for secondary sampling) and draw them all at once. 6.4.4 Qualification judgment
If the test samples of routine inspection meet the requirements of Articles 4.2 to 4.5, they are qualified products. If the number of qualified products meets the requirements of Table 8, the routine inspection is judged to be qualified, otherwise it is unqualified; b. If the routine inspection is unqualified, the products produced in this period are judged to be unqualified. Unqualified products shall not be shipped out of the factory and production shall be stopped. Production can only be resumed after the reasons are found and effective measures are taken. For the first batch of products after the resumption of production, routine inspection must be carried out again, and production can only be continued after the inspection is qualified.
Products judged as unqualified must be repaired or screened, and only after passing routine inspection can they be considered qualified. 6.4.5 Handling of inspection results
For products produced during the period that have failed routine inspection and have been shipped, the quality responsibility shall be borne by the manufacturer. The specific handling method shall be negotiated and resolved by the supply and demand parties;
Products that have undergone routine inspection shall not be shipped as genuine products b.
7 Marking, packaging, transportation, storage
7.1 Marking
The model and trademark shall be marked on the finished magnetic head. a.
The marking on the packaging box shall comply with the provisions of GB191. 7.2 Packaging
The inner packaging of the magnetic head shall ensure that the working surface of the magnetic head is not scratched and the magnetic heads do not collide with each other. 7.3 Transportation
The packaged magnetic head can be transported by normal land, sea and air transportation. During transportation, it should be avoided from direct rain and snow or exposure to the sun. 7.4 Storage
The packaged magnetic heads should be stored in a warehouse with a temperature of -15-40℃, a relative humidity of no more than 80%, and no acidic or other harmful gases around. The storage period should not exceed six months. Otherwise, the delivery inspection should be carried out again before leaving the factory, and only qualified ones can leave the factory. 11
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.