Lighting unit

Abstract

The utility model relates to a lighting unit, and relates to the field of railway signal lamps, the lighting unit comprises a shell and a circuit board arranged in the shell, the shell is provided with a mounting groove for mounting the circuit board, the shell is provided with a cooling fan for cooling the circuit board, the shell is provided with a mounting cavity for mounting the cooling fan, and the mounting cavity is provided with a mounting groove for mounting the circuit board. The installation cavity is communicated with the installation groove, and a ventilation opening for ventilation of the cooling fan is formed in the shell. The lighting unit has the effects of improving the use stability of the lighting unit and improving the heat dissipation speed.

Description

Technical Field

[0001] The present application relates to the field of railway signal lamps, and in particular to a lighting unit. Background Art

[0002] The lighting unit is a device for lighting a light bulb.

[0003] In the prior art, rail traffic lights generally require the use of a lighting unit, which generally includes a housing and a circuit board disposed in the housing. The circuit board includes an amplifier for changing the magnitude of the current and a rectifier for converting alternating current into direct current. After the current is input into the lighting unit, it is converted into a current directly used by the light bulb through the amplifier and the rectifier. The circuit board generally also includes a protection device for protecting the circuit. The protection device is used to reduce the current when the current is too large. The protection device is generally composed of a fuse.

[0004] When the lighting unit is in use, the current is scaled multiple times on the circuit board, which easily generates a lot of heat, causing the fuse to blow prematurely before the current reaches the threshold. Utility Model Content

[0005] In order to improve the stability of the use of the lighting unit and increase the heat dissipation speed, the present application provides a lighting unit.

[0006] A lighting unit comprises a shell and a circuit board arranged in the shell, the shell is provided with a mounting groove for mounting the circuit board, the shell is provided with a cooling fan for dissipating heat from the circuit board, the shell is provided with a mounting cavity for mounting the cooling fan, the mounting cavity is communicated with the mounting groove, and the shell is provided with a ventilating port for ventilation of the cooling fan.

[0007] By adopting the above technical solution, the air is discharged from the installation groove through the vent by the heat dissipation fan, thereby increasing the air exchange speed inside and outside the lighting unit, reducing the accumulation of heat on the circuit board that causes the fuse to blow prematurely, and thereby improving the stability of the lighting unit.

[0008] Preferably, a heat dissipation port is provided on the housing for dissipating heat from the circuit board, and the heat dissipation port is communicated with the mounting groove.

[0009] By adopting the above technical solution, when the air in the installation slot is discharged by the cooling fan, the outside air enters the installation slot from the heat dissipation port, thereby increasing the air exchange speed inside and outside the lighting unit, reducing the accumulation of heat on the circuit board that causes the fuse to blow prematurely, and thereby improving the stability of the lighting unit.

[0010] Preferably, a baffle for shielding the heat dissipation port is provided on the housing, and the baffle is located on a side of the heat dissipation port away from the heat dissipation fan.

[0011] By adopting the above technical solution, the heat dissipation port is shielded by the baffle, thereby reducing the situation where impurities enter the installation groove from the heat dissipation port and cause damage to the circuit board, thereby improving the stability of the lighting unit.

[0012] Preferably, a shielding plate is provided on a side of the baffle away from the housing, and the shielding plate faces a side close to the heat dissipation port.

[0013] By adopting the above technical solution, the shield and the baffle cooperate to shield the heat dissipation port, thereby further reducing the situation where impurities enter the installation groove from the heat dissipation port and cause damage to the circuit board, thereby improving the stability of the lighting unit.

[0014] Preferably, a side of the heat dissipation fan close to the housing is symmetrically provided with a rib, and the rib is in conflict with the housing.

[0015] By adopting the above technical solution, the cooling fan is fixed to the casing by passing bolts through the retaining edge and fixing them on the casing, thereby reducing the deviation of the cooling fan on the casing causing the cooling fan to not correspond to the exhaust hole, thereby improving the stability of the cooling fan installation.

[0016] Preferably, a clamping joint is provided on one side of the retaining edge close to the shell, and a clamping hole for clamping and fixing the clamping joint is provided on the shell.

[0017] By adopting the above technical solution, the card connector is pressed against the shell in the card connector hole, thereby fixing the cooling fan on the shell, reducing the situation where the cooling fan is offset on the shell and causing the cooling fan to not correspond to the exhaust hole, thereby improving the stability of the cooling fan installation.

[0018] Preferably, a deformation groove for deformation of the card connector is provided on the card connector.

[0019] By adopting the above technical solution, when the card joint enters the card hole, the card joint is pressed and then enters the deformation groove. When the card joint completely enters the card hole, the card joint is not pressed and then restores the deformation, thereby pressing against the outer shell in the card hole, thereby reducing the wear of the card joint and improving the stability of the card joint.

[0020] Preferably, the shell is provided with a cover plate for closing the mounting groove, the cover plate is provided with a first terminal for inputting a power signal, one end of the first terminal is connected to the circuit board, and the other end of the first terminal is passed through to the outside world, the cover plate is also provided with a second terminal for outputting a signal, one end of the second terminal is connected to the circuit board, and the other end of the second terminal is passed through to the outside world, and the shell is provided with a penetration hole for the first terminal and the second terminal to pass through.

[0021] By adopting the above technical solution, the external signal is input to the circuit board through the first terminal, and the signal on the circuit board is output to the outside through the second terminal, thereby reducing the external interference with the circuit board and improving the stability of the circuit board.

[0022] Preferably, the circuit board includes a receiving device, an amplifying device and a rectifying device;

[0023] The receiving device is used to receive the power signal and transmit it to the amplifying device. The amplifying device is connected to the receiving device to receive the power signal and output the amplified signal. The rectifier is connected to the amplifying device to receive the AC amplified signal and output the DC rectified signal.

[0024] When the receiving device receives the power signal and transmits it to the amplifying device, the amplifying device adjusts the amplitude of the power signal into an amplified signal for normal operation of the light bulb, and the rectifying device converts the AC amplified signal into a DC rectified signal.

[0025] By adopting the above technical solution, the input current is generally 220V or 380V AC, and the current required by the bulb is generally 12V DC. After the current enters the amplifying device through the receiving device, it is first converted into 12V AC, and then converted into 12V DC through the rectifying device, thereby completing the current conversion and improving the stability of the lighting unit.

[0026] Preferably, the circuit board further comprises a protection device;

[0027] The protection device is connected to the rectifier device to receive the rectified signal and respond to the rectified signal to protect the circuit;

[0028] When the amplitude of the rectified signal is too large, the protection device switches the circuit to reduce the amplitude of the rectified signal.

[0029] By adopting the above technical solution, when the rectified signal is greater than 12V, the fuse in the protection device blows and switches the circuit to increase the resistance in the circuit, thereby reducing the amplitude of the rectified signal, thereby reducing the chance of the bulb burning out and improving the stability of the lighting unit.

[0030] In summary, the present application includes at least one of the following beneficial technical effects:

[0031] 1. The cooling fan discharges air from the installation slot through the vents, thereby increasing the air exchange rate inside and outside the lighting unit, reducing the accumulation of heat on the circuit board that causes the fuse to blow prematurely, and thus improving the stability of the lighting unit;

[0032] 2. The card connector is pressed against the housing in the card connector hole, thereby fixing the cooling fan on the housing, reducing the deviation of the cooling fan on the housing, resulting in the cooling fan and the exhaust hole not corresponding, thereby improving the stability of the cooling fan installation;

[0033] 3. When the amplitude of the rectified signal is too large, the protection device switches the circuit to reduce the amplitude of the rectified signal, thereby reducing the burnout of the bulb and improving the stability of the lighting unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a lighting unit in an embodiment of the present application.

[0035] Figure 2 This is a cross-sectional view of the lighting unit. Figure 1 .

[0036] Figure 3 This is a cross-sectional view of the lighting unit. Figure 2 .

[0037] Figure 4 It is the circuit schematic diagram of the circuit board.

[0038] Explanation of the accompanying drawings: 1. housing; 2. circuit board; 3. mounting slot; 4. cooling fan; 5. mounting cavity; 6. vent; 7. heat dissipation port; 8. baffle; 9. shield; 10. rib; 11. snap joint; 12. snap hole; 13. deformation groove; 14. cover; 15. first terminal; 16. through hole; 17. receiving device; 18. amplifying device; 19. rectifying device; 20. protecting device; 21. mounting frame; 22. embedding slot; 23. second terminal. DETAILED DESCRIPTION

[0039] The following is combined with Figure 1-4 This application is described in further detail.

[0040] Reference Figure 1 and Figure 2The embodiment of the present application discloses a lighting unit, including a housing 1, a circuit board 2, a mounting frame 21, a cover plate 14, a first terminal 15, a second terminal 23, and a cooling fan 4. The circuit board 2 is arranged in the housing 1, and a mounting groove 3 for mounting the circuit board 2 is provided in the housing 1. The housing 1 is provided with a mounting frame 21 for mounting the circuit board 2, and an embedding groove 22 for mounting the circuit board 2 is provided on the mounting frame 21. Both sides of the mounting frame 21 are connected to the housing 1, and the other two sides of the mounting frame 21 do not contact the housing 1. The housing 1 is fixed with a cover plate 14 by screws, and a first terminal 15 for inputting a power signal is provided on the cover plate 14, one end of the first terminal 15 contacts the circuit board 2, and the other end of the first terminal 15 is penetrated to the outside, and a second terminal 23 for outputting a signal is also provided on the cover plate 14, one end of the second terminal 23 contacts the circuit board 2, and the other end of the second terminal 23 is penetrated to the outside, and a penetration hole 16 for the first terminal 15 and the second terminal 23 to penetrate is provided on the cover plate 14. A cooling fan 4 is arranged on the outer shell 1, and an installation cavity 5 for installing the cooling fan 4 is opened on the outer shell 1. The installation cavity 5 is connected with the installation groove 3. The cooling fan 4 blows air outwards. A vent 6 for exhausting the cooling fan 4 is opened on the outer shell 1, and the vent 6 is connected with the installation cavity 5.

[0041] Reference Figure 1 and Figure 2 The housing 1 is provided with heat dissipation openings 7, which are waist-shaped holes. The heat dissipation openings 7 are provided on both sides of the housing 1 that do not conflict with the mounting frame 21. The heat dissipation openings 7 are connected to the mounting grooves 3. The heat dissipation openings 7 are used to accelerate the air exchange rate inside and outside the lighting unit. When the heat dissipation fan 4 blows the air inside the lighting unit outward through the vents 6, the outside air enters the lighting unit from the heat dissipation openings 7. In this embodiment, six heat dissipation openings 7 are symmetrically provided.

[0042] Reference Figure 1 and Figure 2 The housing 1 is integrally provided with a baffle 8 for reducing the situation that impurities enter the mounting groove 3 through the heat dissipation opening 7. The baffle 8 is arranged at the upper edge of the heat dissipation opening 7. The baffle 8 is integrally provided with a shield 9 for further reducing the situation that impurities enter the mounting groove 3 through the heat dissipation opening 7 on the side away from the housing 1. The shield 9 extends toward the direction close to the heat dissipation opening 7. The baffle 8 and the shield 9 make the opening direction of the heat dissipation opening 7 face the ground, thereby reducing the situation that impurities enter the mounting groove 3 through the heat dissipation opening 7.

[0043] Reference Figure 3, ribs 10 are integrally provided on both sides of the cooling fan 4, the ribs 10 are in conflict with the housing 1, and the ribs 10 are fixed to the housing 1 by screws, thereby fixing the cooling fan 4 to the housing 1. A clamping joint 11 is integrally provided on one side of the rib 10 close to the housing 1, and a clamping hole 12 for clamping and fixing the clamping joint 11 is provided on the housing 1, and a deformation groove 13 for deformation of the clamping joint 11 is provided on the opening, and the cooling fan 4 is first clamped and fixed to the housing 1 by the clamping joint 11, and then the cooling fan 4 is fixed to the housing 1 by screws passing through the clamping joint 11.

[0044] Reference Figure 4 The circuit board 2 includes a receiving device 17, an amplifying device 18, a rectifying device 19 and a protecting device 20. The receiving device 17 receives the power signal from the first terminal 15 and transmits it to the amplifying device 18. The amplifying device 18 changes the value of the power signal to convert it into an amplified signal. The rectifying device 19 receives the amplified signal of AC and converts it into a rectified signal of DC. The protecting device 20 detects the rectified signal and increases the resistance of the circuit to reduce the rectified signal when the rectified signal is too large.

[0045] Reference Figure 4 The receiving device 17 is a transformer B1, and both ends of the primary coil of the transformer B1 are respectively connected to the two first terminals 15 to receive the power signal.

[0046] Reference Figure 4 When the first terminal 15 receives the power signal, it is transmitted to the primary coil of the transformer B1, so that the secondary coil of the transformer B2 generates voltage, reducing external interference during transmission.

[0047] Reference Figure 4, the amplifying device 18 includes a transformer B2, a diode D1, a diode D2, a diode D3, a diode D4, a diode D5, a diode D6, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a transistor Q1, a field effect transistor Q2, a transistor Q3 and a field effect transistor Q4. The model of the diode D1, the diode D2, the diode D4 and the diode D5 is FR4002, and the signal of the diode D3 and the diode D6 is MBRD10010. The capacitor C1, the capacitor C2, the capacitor C3 and the capacitor C4 are all 1uf capacitors. The resistor R1 and the resistor R5 are resistors with a resistance value of 1k, the resistor R2, the resistor R4, the resistor R6 and the resistor R8 are resistors with a resistance value of 50k, the resistor R3 and the resistor R7 are resistors with a resistance value of 5k, and the resistor R9 is a resistor with a resistance value of 100. The transistor Q1 is an NPN transistor of model S8050, the transistor Q2 is a PNP transistor of model S8550, the field effect transistor Q2 is an N-type field effect transistor of model 034N06N, and the field effect transistor Q4 is a P-type field effect transistor of model AOD409.

[0048] Reference Figure 4One end of the secondary coil of the transformer B1 is connected to one end of the capacitor C3, and then to one end of the resistor R6 and to the emitter of the transistor Q3. The other end of the resistor R6 is connected to one end of the resistor R5 and then to the base of the transistor Q3. The other end of the resistor R5 is connected to the other end of the capacitor C3 and then to the anode of the diode D4. One end of the resistor R8 is connected to one end of the secondary coil of the transformer B1, the other end of the resistor R8 is connected to the collector of the transistor Q3, and then to one end of the resistor R7 and to the gate of the field effect transistor Q4, the source of the field effect transistor Q4 is connected to one end of the secondary coil of the transformer B1, the drain of the field effect transistor Q4 is connected to the anode of the diode D6, the other end of the resistor R7 is connected to the anode of the diode D5 and then to one end of the capacitor C4, the other end of the capacitor C4 is connected to one end of the secondary coil of the transformer B1, the cathode of the diode D5 is connected to one end of the resistor R9 and then to the anode of the diode D2, the other end of the resistor R9 is connected to the other end of the secondary coil of the transformer B1, the cathode of the diode D2 is connected to one end of the capacitor C2 and then to one end of the resistor R3, the other end of the capacitor C2 is connected to one end of the secondary coil of the transformer B1 and then to one end of the primary coil of the transformer B2, the other end of the resistor R3 is connected to one end of the secondary coil of the transformer B1 and then to one end of the primary coil of the transformer B2, the other end of the resistor R3 is connected to one end of the secondary coil of the transformer B1 and then to one end of the primary coil of the transformer B2. One end is connected to the movable connection of resistor R4 and then to the collector of transistor Q1 and to the gate of field effect transistor Q2, the source of field effect transistor Q2 is connected to one end of the secondary coil of transformer B1, the drain of field effect transistor Q2 is connected to the cathode of diode D3, the anode of diode D3 is connected to the cathode of diode D6, the emitter of transistor Q1 is connected to one end of the secondary coil of transformer B1, the base of transistor Q1 is connected to one end of resistor R1 and then to one end of resistor R2, the other end of resistor R2 is connected to one end of the secondary coil of transformer B1, the other end of resistor R1 is connected to the cathode of diode D1 and then to one end of capacitor C1, the other end of capacitor C1 is connected to one end of the secondary coil of transformer B1, the anode of diode D1 is connected to the cathode of diode D4 and then to the other end of the primary coil of transformer B2, and one end of the primary coil of transformer B2 is connected to the same name end of transformer B2.

[0049] Reference Figure 4 When the power signal is input to the amplifier 18, the power signal is continuously scaled by transistor Q1, field effect transistor Q2, transistor Q3 and field effect transistor Q4, and then input to the primary coil of transformer B2, thereby generating an AC amplified signal with an amplitude of 12V in the secondary coil of transformer B2.

[0050] Reference Figure 4The rectifier 19 includes a fuse F1, a bridge rectifier Z1, a voltage regulator Q6, a relay J1, a capacitor C6, a capacitor C7, a resistor R13, a resistor R14, a transistor Q5, and a diode D8. The model of the fuse F1 is R60-025, the model of the bridge rectifier Z1 is KBJ410, the model of the voltage regulator Q6 is 7805, the model of the relay J1 is JQX-13F, the capacitor C6 is a 47uf electrolytic capacitor with a rated voltage of 50v, the capacitor C6 is a 100uf electrolytic capacitor with a rated voltage of 10v, the resistor R13 is a resistor with a resistance of 5K, the resistor R14 is a resistor with a resistance of 50K, the transistor Q5 is an NPN transistor with a model of S8050, and the model of the diode D8 is 1N4007.

[0051] Reference Figure 4 , one end of the fuse F1 is connected to the same-name end of the transformer B2, the other end of the fuse F1 is connected to pin 1 of the bridge rectifier Z1, pin 2 of the bridge rectifier Z1 is connected to the anode of the capacitor C6 and then to the input end of the voltage regulator Q6, the cathode of the capacitor C6 is connected to pin 4 of the bridge rectifier Z1, the ground end of the voltage regulator Q6 is connected to pin 4 of the bridge rectifier Z1, the output end of the voltage regulator Q6 is connected to the anode of the capacitor C7 and then to the resistor R13, and the cathode of the capacitor C6 is connected to the ground end of the voltage regulator Q6 and the output end of the voltage regulator Q6 is connected to the anode of the capacitor C7 and then to the resistor R13. The cathode of capacitor C7 is connected to pin 4 of the bridge rectifier Z1, the output end of the voltage regulator Q6 is connected to the cathode of the diode D8 and then to one end of the relay J1, the anode of the diode D8 is connected to the collector of the transistor Q5 and then to the other end of the relay J1, the emitter of the transistor Q5 is connected to pin 4 of the bridge rectifier Z1, the base of the transistor Q5 is connected to one end of the resistor R14, and the other end of the resistor R14 is connected to pin 4 of the bridge rectifier Z1.

[0052] Reference Figure 4 When the amplified signal is input to the rectifier 19, the amplified AC signal is converted into a DC signal with the same amplitude through the bridge rectifier Z1, and the signal voltage is stabilized through the voltage regulator Q6, the relay J1 and the transistor Q5, and the rectifier 19 is protected by the fuse F1.

[0053] Reference Figure 4The protection device 20 includes a photocoupler GD1, a fuse F2, a fuse F3, a resistor R10, a resistor R11, a resistor R12, a resistor R15, a capacitor C5, a capacitor C8, a diode D7 and a diode D9. The model of the photocoupler GD1 is PC817, the models of the fuses F2 and F3 are R60-025, the resistors R10 and R12 are resistors with a resistance value of 100, the resistor R11 is a resistor with a resistance value of 2k, the resistor R15 is a resistor with a resistance value of 100, the capacitor C5 is an electrolytic capacitor of 100uf, the rated voltage is 25v, the capacitor C8 is an electrolytic capacitor of 470uf, the rated voltage is 25v, the model of the diode D7 is 1N4148, and the model of the diode D9 is FR4002.

[0054] Reference Figure 4 , one end of the resistor R15 is connected to the 3rd pin of the bridge rectifier Z1, the other end of the resistor R15 is connected to one end of the fuse F2 and then to one end of the fuse F3, the other end of the fuse F2 is connected to the opposite end of the transformer B2, the other end of the fuse F3 is connected to one end of the resistor R12 and then to the anode of the diode D3, the other end of the resistor R12 is connected to the anode of the diode D9, the cathode of the diode D9 is connected to a section of the resistor R11 and then to the anode of the capacitor C5, the other end of the resistor R11 is connected to the photocoupler G Pin 1 of D1 is connected, pin 2 of the photocoupler GD1 is connected to the other end of the capacitor C5 and then to one end of the resistor R10, the other end of the resistor R10 is connected to the same-name end of the transformer B2, pin 3 of the photocoupler GD1 is connected to pin 4 of the bridge rectifier Z1, pin 4 of the photocoupler GD1 is connected to the other end of the resistor R13 and then to the anode of the capacitor C8 and to the anode of the diode D7, the cathode of the capacitor C8 is connected to pin 4 of the bridge rectifier Z1, and the cathode of the diode D7 is connected to the base of the transistor Q5.

[0055] Reference Figure 4 When the rectified signal is input to the protection circuit, the rectified signal first passes through the fuse F2, thereby short-circuiting the fuse F3. When the rectified signal is too large, the fuse F2 blows, and the rectified signal passes through the fuse F3. The amplitude of the rectified signal is reduced through the resistor on the fuse F3 and the photocoupler GD1, thereby providing a stable rectified signal. When the rectified signal is too large again, the fuse F3 blows, thereby protecting the circuit.

[0056] Working principle:

[0057] The cooling fan 4 draws air from the mounting slot 3 and discharges it to the outside through the vent 6, thereby forming a negative pressure environment in the mounting slot 3, prompting outside air to enter the mounting slot 3 through the cooling port 7, thereby accelerating the air exchange between the inside and outside of the lighting unit and improving the cooling efficiency of the lighting unit.

[0058] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A lighting unit, comprising a housing (1) and a circuit board (2) arranged in the housing (1), characterized in that: The housing (1) is provided with a mounting groove (3) for mounting the circuit board (2); the housing (1) is provided with a cooling fan (4) for cooling the circuit board (2); the housing (1) is provided with a mounting cavity (5) for mounting the cooling fan (4); the mounting cavity (5) is communicated with the mounting groove (3); and the housing (1) is provided with a ventilation hole (6) for ventilation of the cooling fan (4).

2. A lighting unit according to claim 1, characterized in that: The housing (1) is provided with a heat dissipation opening (7) for dissipating heat from the circuit board (2), and the heat dissipation opening (7) is in communication with the mounting groove (3).

3. A lighting unit according to claim 2, characterized in that: The housing (1) is provided with a baffle (8) for shielding the heat dissipation opening (7); the baffle (8) is located on a side of the heat dissipation opening (7) away from the heat dissipation fan (4).

4. A lighting unit according to claim 3, characterized in that: A shielding plate (9) is provided on the side of the baffle plate (8) away from the housing (1), and the shielding plate (9) faces the side close to the heat dissipation port (7).

5. A lighting unit according to claim 1, characterized in that: A rib (10) is symmetrically arranged on one side of the heat dissipation fan (4) close to the outer shell (1), and the rib (10) is in contact with the outer shell (1).

6. A lighting unit according to claim 5, characterized in that: A clamping joint (11) is provided on one side of the retaining edge (10) close to the housing (1), and a clamping hole (12) for clamping and fixing the clamping joint (11) is provided on the housing (1).

7. A lighting unit according to claim 6, characterized in that: The card connector (11) is provided with a deformation groove (13) for the card connector (11) to deform.

8. A lighting unit according to claim 1, characterized in that: The housing (1) is provided with a cover plate (14) for closing the mounting groove (3); the cover plate (14) is provided with a first terminal (15) for inputting a power signal; one end of the first terminal (15) is connected to the circuit board (2); the other end of the first terminal (15) is extended to the outside; the cover plate (14) is also provided with a second terminal (23) for outputting a signal; one end of the second terminal (23) is connected to the circuit board (2); the other end of the second terminal (23) is extended to the outside; and the housing (1) is provided with a through hole (16) for the first terminal (15) and the second terminal (23) to be extended.

9. A lighting unit according to claim 8, characterized in that: The circuit board (2) comprises a receiving device (17), an amplifying device (18) and a rectifying device (19); The receiving device (17) is used to receive the power supply signal and transmit it to the amplifying device (18); the amplifying device (18) is connected to the receiving device (17) to receive the power supply signal and output the amplified signal; the rectifier (19) is connected to the amplifying device (18) to receive the AC amplified signal and output the DC rectified signal; When the receiving device (17) receives the power signal and transmits it to the amplifying device (18), the amplifying device (18) adjusts the amplitude of the power signal into an amplified signal for normal operation of the light bulb, and the rectifier (19) converts the AC amplified signal into a DC rectified signal.

10. A lighting unit according to claim 9, characterized in that: The circuit board (2) further includes a protection device (20); The protection device (20) is connected to the rectifier device (19) to receive the rectified signal and respond to the rectified signal to protect the circuit; When the amplitude of the rectified signal is too large, the protection device (20) switches the circuit to reduce the amplitude of the rectified signal.

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