The speaker is also called "horn". It is a very common electro-acoustic transducing device, which can be seen in audible electrical and electronic equipment. It is often used in home appliances, including speakers, televisions, mobile phones, computers, etc. The principle, how much do you know? Let's analyze it with Xiaobian.
1, the structure of the speakerThere are many types of speakers, but the basic working principle is similar. They are all components that convert electrical signals into sound signals for playback. Currently the most widely used is the electric speaker, which consists of a diaphragm, a voice coil, a permanent magnet, a bracket, and the like.
The structure of the electric speaker is shown in Figure 1:
Figure 1 Structure of the electric speaker
The structure of the dome speaker is shown in Figure 2:
Figure 2 Structure of the dome speaker
2, the working principle of the speakerWhen the voice coil of the speaker is connected to the audio current, the voice coil generates an alternating magnetic field under the action of current, and the permanent magnet also produces a constant magnetic field of constant magnitude and direction. Since the magnitude and direction of the magnetic field generated by the voice coil are constantly changing with the change of the audio current, the interaction of the two magnetic fields causes the voice coil to move perpendicular to the direction of the current in the voice coil, since the voice coil is connected to the diaphragm, thereby The diaphragm is driven to generate vibration, and the vibration of the diaphragm causes vibration of the air to emit sound. When the current input to the voice coil is larger, the force of the magnetic field is greater, and the amplitude of the vibration of the diaphragm is greater, and the sound is louder. The part of the speaker that emits the high sound is mainly in the center of the diaphragm. When the center material of the diaphragm of the speaker is harder, the sound effect of the reproduction is better. The part of the speaker that emits the bass is mainly at the edge of the diaphragm. If the edge of the diaphragm of the speaker is soft and the diameter of the cone is large, the bass effect of the speaker is better. In addition, dome speakers are used in many speakers in the market today. As we all know, because the tweeter has a high operating frequency, its diaphragm will move at high speed in the magnetic air gap of the permanent magnet when the high-pitched sound is reproduced. Therefore, the diaphragm of the tweeter is required to be able to respond to transient high-frequency signals. Make a quick response. And it can withstand the air pressure generated by high-speed motion, so the material for the diaphragm is required to be light in quality and have sufficient strength.
3. Trouble shooting and analysis of speaker failureReason 1: The voice coil is open
The voice coil is broken. Poor incoming or man-made damage.
Precaution:
a: Check the quality of the voice coil before production, such as whether the lead wire is easy to break, whether the voice coil wire is broken, whether there is a short circuit or an open circuit.
b: Pay special attention to whether the voice coil leads are disconnected.
Reason 2: Broken silk thread
The silk wire and the paper cup are in the eye part and the soldering part of the terminal is broken. Because the silk thread is linearly drawn, the silk thread is too short, the silk thread is not curved when it is drawn, and the silk thread is drawn in the paper cone. The silk thread is not covered with the eight-character rubber or the eight-shaped rubber does not completely cover the silk thread.
Precaution:
a: The silk thread cannot be drawn in a straight line, so it is easy to break.
b: The silk thread can't stay too long, which will cause the paper silk to produce a paper cone, especially the woofer.
c: The exit position of the silk thread can't be too close to the terminal board, so that the force part of the silk thread is reduced, and the speaker is easy to break when working for a long time. When the silk thread is out of the dust cap, the silk thread should be S or 7-shaped on both sides, so that there is sufficient margin when the silk thread vibrates, and the folding force generated by the speaker during operation is evenly distributed on the silk thread. Can not let the Jinsi line force point.
d: The silk thread should be taken along the back of the diaphragm, and it will be directed upwards or downwards along the cone of the paper, and then led to the terminal in a certain arc to reduce the bending force caused by the cone when it vibrates.
e: When the silk thread is taken out from the top of the cone, it can be drawn up along the top of the cone of the cone, and then led to the terminal according to a certain arc shape; it can also be drawn from the cone of the diaphragm to the terminal and form a certain arc.
f: The eight-character rubber should completely cover the place where the silk thread is on the back of the diaphragm, but the glue coverage should not be too long, so that the force area of ​​the silk thread is too large and broken.
g: When soldering the terminal strip, the soldering time should not be too long, and the soldering wire should be oxidized. The solder on the silk wire should not be too long to cover the surface, so that the silk wire can be hardened without folding. The same is true when welding the front line.
Reason 3: The voice coil leads to the line break
Generally, the lead wire is not pressed or the margin is not enough, and the splayed rubber does not cover the voice coil lead.
Precaution:
a: When making production, be sure to let the voice coil lead wire cling to the diaphragm;
b: When taking out the voice coil lead wire, pay attention to make it have enough margin. In order to ensure that the lead wire is not straightened when the speaker is at the maximum amplitude, it is best to make the voice coil lead wire line along the paper cone into the S line or in the cone of the diaphragm. The part makes the voice coil lead line a semicircle.
c: The octagonal glue should completely cover the voice coil lead wire, especially the cone of the paper cone.
d: Do not cut too low or cut the voice coil lead when trimming.
Reason 4: Solder wire part solder joint
Jin silk wire and voice coil lead wire, silk wire and terminal.
Precaution:
a: To control the welding time, let the solder melt sufficiently.
b: Before the production, check whether the voice coil lead wire insulation paint is removed, whether the lead wire is oxidized or tinned.
Reason 5: The voice coil is burnt out
If the current is too large, the voice coil is burned out, and the voice coil generates too much heat, which causes the paint layer to overheat and deteriorate.
Precaution:
a: Listening, aging, etc. according to the rated power of the speaker itself.
b: The voice coil wire is made of high temperature resistant enameled wire, while the insulating paint and adhesive and the skeleton are also made of high temperature resistant materials.
c: Improve the heat dissipation method of the speaker: use a skeleton with good heat dissipation, a good elastic wave, a bottom of the basin frame, a voice coil skeleton, a bomb wave, a diaphragm cone, and a T-iron vent hole.
Reason 6: The voice coil sinks or floats to break the voice coil line
Precaution:
a: The center rubber is not resistant to high temperature and is detached from the elastic wave and the diaphragm. If it is a one-component center glue, it can be changed to a high-temperature two-component center glue.
b: Improve the heat dissipation effect of the magnetic circuit.
C: The center rubber is not stuck to the paper cone and the bomb or glue does not dry out.
The speaker has an abnormal sound:
Reason 1: Degumming of the center glue part
Due to high operating temperature, excessive power, production process and other reasons.
Precaution:
a: Use a suitable center glue according to the rated power of the speaker.
b: When the speaker is subjected to various experiments or listening, it is allowed to work within the rated power and the specified frequency range.
c: The center rubber of the two components should be thoroughly mixed according to the specified ratio, and the diaphragm should be placed in the glue operable time.
d: Check whether the center glue is completely dry before dialing the sound gauge, so as to avoid blindly removing the sound ruler and causing the voice coil to shift and damage the center glue curing structure.
e: Check whether the center glue has broken glue or lack of glue.
Reason 2: voice coil deformation, etc.
Precaution:
a: Before the production, check the voice coil skeleton for deformation.
b: Pay attention to whether the sticker on the surface of the voice coil has foaming, whether it is firm or not, and whether the surface is rolled up, so as to prevent the sticker from being thermally expanded and the friction generated by the Huasi to produce an abnormal sound.
c: Use a high temperature resistant voice coil skeleton.
d: Check the sound gauge for glue on the sound gauge.
Reason 3: voice coil line
Precaution:
a: Check the voice coil for loose lines and jumpers before production, and whether the winding is compact.
b: Let the speaker work within the rated power range.
c: The self-adhesive force of the voice coil wire is not enough, and it cannot withstand high temperature. A good voice coil self-adhesive voice coil wire should be stuck tighter at the rated high temperature.
Cause 4: The voice coil tail is rolled up
When the amplitude is large, the voice coil is rubbed into the T-iron or the washer.
Precaution:
a: Check if the end of the voice coil is deformed first.
b: If the voice coil is positioned too low, adjust the center of the voice coil face to the same plane as the center of the Huawei. (or according to BOM data)
c: If the compliant material ages or loses its elasticity, replace it with a new one.
d: The outer diameter of the gauge is too small. During production, the voice coil is loose and the speaker is hitting the bottom of the T iron when it vibrates.
Reason 5: The magnetic gap has debris
Such as iron filings, glue or glue stuck in the voice coil.
Precaution:
a: When making the magnetic circuit, wipe the magnetic particles on the inner wall of the magnet and check whether the T-iron and the Huashi are peeling off.
b: Dust the dust in the magnetic circuit before the sound coil.
c: Dust-proof measures should be taken throughout the production of the speaker.
d: When playing the rubber gelatin, please be careful not to let the glue overflow or flow to the middle hole of the washer.
e: Check if the hole in the elastic wave is too large and the middle hole is damaged to prevent the center glue from flowing to the lower part of the voice coil.
f: The glue and the glue on the magnetic gauge must be cleaned first.
g: Check if there is glue on the voice coil surface during production.
h: When producing a speaker with a small difference between the inner diameter of the magnet and the inner diameter of the huasi, pay attention to the magnetic circuit glue to be placed outside the inner diameter of the magnet to prevent the magnetic circuit glue from spilling into the middle hole of the huasi and causing the wiper.
Cause 6: Diaphragm deformation produces displacement
Precaution:
a: During production, be careful not to press the paper cone vigorously by hand to deform the paper cone to cause the rubbing ring. Especially the metal diaphragm is strong in rigidity, but the toughness is very poor, and it is difficult to recover after deformation.
b: The incoming material needs to check whether the paper cone is deformed.
c: If it is a paper material, pay attention to moisture and deformation from moisture.
Reason 7: Paper cone rupture
The diaphragm is damp or has been used for a long time.
Precaution:
a: The cone speaker should be specially protected from moisture, such as being exposed outdoors at night, being exposed to rain.
b: The speaker should not be aged for a long time or excessively high power aging to prevent the cone of the cone from being broken and being broken.
c: When the speaker is operated for a long time and at a very high power, the diaphragm will be damaged due to excessive amplitude.
e. Punching or other causes may cause the cone to rupture, requiring attention to operation.
Reason 8: Folding ring aging loses elasticity or degumming
Precaution:
a: Avoid using materials that are corrosive to the folding ring during the production process.
b: When applying the edge glue, the amount of glue must be sufficient to allow the limited bonding area to withstand large vibrations.
c: The edge glue should make the folding ring and the basin frame completely adhered, so as to avoid the gap and the relative rotation of the folding ring and the basin frame to generate abnormal sound, especially the bubble edge.
d: It is necessary to check whether the glued surface of the basin frame and the folding ring is flat, to prevent the unevenness of the folding ring from being debonded and the bonding is not good.
e: If the ring is aging, moldy, whitish, and inelastic, replace the ring.
f: The folding ring should be placed in time after the application of the edge glue. Do not put the film on the edge of the edge.
Reason 9: Elastic wave aging has lost its elasticity
Or the elastic wave deformation, fracture, the glue part of the elastic wave is not well.
Precaution:
a: When playing the elastic wave glue, make sure that there is a uniform gap of glue on the outer surface of the elastic wave and the frame of the basin, and let the elastic wave penetrate into it, and the elastic wave should be placed in time.
b: It is not possible to use elastic waves with poor elasticity or even no elasticity.
c: Do not use any damage or deformation.
d: Do not let the elastic wave damp and other diluted substances make it lose its elasticity.
Reason 10: Deformation of the basin
Precaution:
a: Do not produce the deformation of the basin.
b: Do not drop the speaker during the production process, causing the basin frame to deform.
Reason 11: The T-pillar is rusted and off center.
Precaution:
a: Do not use the T-iron plating layer or plating.
b: Do not use the iron column in the T iron column for a long time.
c: Check the T-iron column for looseness, burrs, etc.
d: Do not use magnetic gauges with gaps.
Reason 12: Noise is generated between the washer and the basin frame
Precaution:
a: The wind glue is played too little or not at all.
b: There is deformation at the bottom of the basin frame, and it should be selected before production.
c: The surface of the washer is uneven, and air leakage occurs.
d. Huasi riveting is not limited, there are loose or gaps
Reason 13: The silk thread hits the paper cone and produces noise.
Precaution:
a: The silk thread should be produced according to the specified length, not too long.
b: After the silk thread comes out of the paper cone, it must be pressed upwards or downwards according to the arc of the paper cone.
c: If the silk thread is lower, you can pull it out from the cone of the paper cone and pull it to the terminal in a certain arc.
other
Reason 14: The mating glue is not well-made to produce a murmur.
Cause 15: The dust cap is not glued to produce noise.
Cause 16: Noise is generated for other reasons such as design or material.
Cause 17: The ring does not produce a murmur
Precaution:
a: The basin frame and the Huashi and T-iron are not concentric. When feeding, pay attention to check the screw hole at the bottom of the basin frame, whether the Chinese tapping is concentric with the middle hole;
b: the folding ring is not upright;
c: The gasket is offset. When the gasket is placed, it cannot be smashed. When the plate is placed, the plate cannot be dragged, and it should be placed vertically;
d: The inner diameter of the gasket is small and the ring is pressed.
The speaker has intermittent sound
Cause 1: The voice coil lead wire is broken but has contact
Precaution:
a: Excessive force is applied when winding the lead, and no margin is given to the voice coil.
b: The eight-character glue does not completely cover the voice coil lead wire or does not hit the eight-character glue.
c: The voice coil lead wire cannot be deliberately folded before production.
Reason 2: Welded joints
Precaution:
a: Solder should be in place, solder joints require bright, no solder joints.
b: Check the voice coil lead for stripping, tinning, and oxidation.
Reason 3: Brocade wire breaks, bad contact
Precaution:
a: If the silk thread near the paper cone is broken, the silk thread is too short, the eight-character glue is too small, and the glue covered on the silk thread is too small; the eight-character glue should be controlled during production.
b: If it is in the arc of the silk thread, it is generally a straight angle of the silk thread and the force point is broken. The production of the silk thread should form a large arc to the paper cone. Consider soft rubber on the back side.
c: If the cotton thread is broken near the terminal board, the welding time is too long, so that the tin spot welding is too long, and the silk wire is oxidized so that the silk thread is too hard to be folded.
24 hours mechanical timer
Instant indicator
Min.setting time:15 minutes. Max.setting timer:24 hours
With hand switch,can be switched to operating and
setting at any time
Instructions:
1. Set program: 1 pin is equivalent to 15 minutes. Determine desired start time and push down pins until desired
off time.
For instance, if you want electrical devices to work from 8:00am to 11:00am and from 13:00pm to 17:00pm, you
just need to put down allthe pins between the three period time.
2. Set the current time: Turning the dial clockwise until the arrow pointing to
current time.
For example,if now it is 8:00 am, please turn the dial and make sure the
arrow point to 8. (See the picture.)
3. Plug the electrical device directly into the timer. Make sure the electrical
device is power-on.
4. Plug the timer into electrical outlet and the electrical device will be work
according to the setting program.
Note: = Normal Ope n = Timing
Make sure the switch on the Timing position. If it
is on the [Normal Open" mode, the electrical device is
always power-on and the timer function no work.
Specifications:
|
Rated Voltage, Current and Power |
As shown on the label |
|
Time Setting Range |
15minutes24hours |
|
Working Temperature |
-10℃?+55℃ |
|
Operation |
Clockwise |
|
Insulation Resistance |
>100M |
|
Inherent Loss |
≤1W |
Application:
1. To enable high-power electric appliances to run automatically at off-peak time if there is different electricity
price according to different periods of time in some areas.
2. To use for electric appliances which need time control, such as water heaters, air conditioners, drinking
fountains, rice cookers, advertising lights and so on.
3. To control the charging time. For example, battery of electric bikes or mobile phones, storage batteries, etc.
4. Occasions which need switch on/off frequently, like interval spray irrigation for flowersand lawn, cyclical
adding oxygen to fish jar, fountains and so on.
5. Home safety precautions and lighting.
Caution:
1.D o not exceed the maximum ratings of the timer.
2.M ust reset the current time after power failure.
3.D o not plug the timer directly into the working electrical appliances.
4.U nless changing the setting, keep the program same every day.
5.D o not disassemble timer by yourself. Professionals service are needed for maintenance.
6.T his item is only for indoor use.
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