A refrigerated container control circuit

Abstract

The present application discloses a refrigerated container control circuit, which relates to the technical field of circuit control. It includes a relay control unit composed of a triode Q3 and a triode Q4 arranged in parallel, a switching triode Q1 and a switching triode Q2 arranged in parallel, and an amplifying triode Q6 and an amplifying triode Q5 arranged in parallel. The collector of the switching triode Q2 is connected to the emitter of the amplifying triode Q5, the collector of the switching triode Q1 is connected to the emitter of the amplifying triode Q6, and a TVS tube 7 is connected in series between the collector of the switching triode Q1 and the emitter of the amplifying triode Q5. The technical advantages of the present application are as follows: The relay control unit effectively prevents the relay from disconnecting under unstable voltage conditions, improving the stability of the refrigerated container under the powered state; by setting the TVS tube 7, the relay circuit can be protected, effectively preventing its main body from being burned; through the plug-in terminal and the annular turning plate, the power supply posture is inclined, ensuring the rainproof effect during power supply.

Description

Technical Field

[0001] The present application relates to the technical field of circuit control, and particularly to a control circuit for a refrigerated container. Background Art

[0002] With the booming rise of the cold chain logistics industry, refrigerated containers, as a crucial link in safeguarding the quality and safety of temperature-sensitive goods, have increasingly attracted industry attention for their effectiveness and reliability. Traditional refrigerated container technology emphasizes maintaining a constant and suitable temperature environment inside the container, which critically depends on the stable operation of the refrigeration system, and the continuous operation of this system is based on a reliable power supply. During long-distance transportation or short-term stops, traditional strategies tend to rely on external power sources (such as port facilities, warehousing centers, or portable generators) to ensure the uninterrupted operation of the refrigeration system. In this process, the safety and stability of the power supply link become of utmost importance because any power interruption or abnormal circuit can directly affect the refrigeration efficiency and thus pose a risk to the freshness and quality of the goods inside the container. Therefore, enhancing the stability and safety of the power supply system is crucial for ensuring the quality of goods throughout the cold chain logistics.

[0003] In the daily operation of refrigerated containers, ensuring the stability and safety of system operation is one of the key challenges faced by technicians. In particular, how to quickly and effectively cut off the power supply when facing a circuit fault, or maintain the connection of the relay when the circuit is unstable to prevent potential electrical disasters and protect the integrity of the goods and equipment inside the container has become a technical problem that the industry urgently needs to overcome. In addition, when a refrigerated container is connected to an external power source, the connection process of the plug cannot be ignored. The design of the plug needs to fully consider the requirements of dust and rain protection to ensure good electrical contact under various weather conditions. Before formal power supply, a detection mechanism for the plug insertion state also needs to be introduced to prevent power interruption or short circuit problems caused by poor contact and avoid unnecessary losses. Summary of the Invention

[0004] The present device provides a control circuit for a refrigerated container, and the specific implementation is as follows:

[0005] A relay control unit composed of a triode Q3 and a triode Q4 arranged in parallel, the emitters of both are respectively connected to the 12V VCC after being serially connected with a resistor R25 and a resistor R24, the base of the triode Q3 is connected to the RLY ON signal through a resistor R30, and the base of the triode Q4 is connected to the RLY OFF signal through a resistor R31;

[0006] The switching triodes Q1 and Q2 are arranged in parallel. The base of the switching triode Q1 is connected to the emitter of the triode Q3 through the resistor R27. The base of the switching triode Q2 is connected to the emitter of the triode Q4 through the resistor R26. And the emitters of the switching triodes Q1 and Q2 are both connected to the 12V VCC.

[0007] The amplifying triodes Q6 and Q5 are arranged in parallel. The collector of the switching triode Q2 is connected to the emitter of the amplifying triode Q5. The collector of the switching triode Q1 is connected to the emitter of the amplifying triode Q6. And a TVS tube 7 is connected in series between the collector of the switching triode Q1 and the emitter of the amplifying triode Q5. The 1st pin of OUT1 is connected in series on the collector of the switching triode Q2. The 2nd pin of OUT1 is connected in series on the collector of the switching triode Q1.

[0008] The bases of the triodes Q3, Q4, amplifying triodes Q6 and Q5 are respectively connected to GND after being connected in series with resistors. And the collectors of the amplifying triodes Q6 and Q5 are directly connected to GND. The collectors of the triodes Q3 and Q4 are connected to GND after being connected in series with the resistors R36 and R35. By the relay control unit, the principle of magnetic holding effectively prevents the relay from disconnecting under the condition of unstable voltage. The TVS tube 7 is used for circuit protection and anti-burning.

[0009] Based on the above technical solutions, by configuring the relay control unit, the risk of accidental disconnection of the relay during voltage fluctuation is effectively avoided, and the stability of the refrigerated container during power supply is significantly enhanced.

[0010] Preferably, it further includes an opto-isolator U7. Its 1st pin accesses the RLY ON signal. Its 2nd pin is connected to GND through the resistor R53. Its 3rd pin is directly connected to GND. It also includes the resistors R46 and R49 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the 4th pin of the opto-isolator U7. And a light-emitting diode D16 is connected in series on the resistor R46. The 4th pin of the opto-isolator U7 is also connected to the PINT ON signal through the resistor R51. The PINT ON signal is connected to the 41st pin of the controller.

[0011] Preferably, it further includes an opto-isolator U8. Its 1st pin accesses the RLY OFF signal. Its 2nd pin is connected to GND through the resistor R54. Its 3rd pin is directly connected to GND. It also includes the resistors R50 and R47 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the 4th pin of the opto-isolator U8. And a light-emitting diode D17 is connected in series on the resistor R47. The 4th pin of the opto-isolator U8 is also connected to the PINT OFF signal through the resistor R51. The PINT OFF signal is connected to the 42nd pin of the controller.

[0012] Preferably, it further includes an optocoupler U4. Its pin 1 is connected to the 12V VCC through a resistor R32. Its pin 2 is connected to the CloseState LED signal, and its pin 2 is also connected to the pin 1 of P4. The pin 2 of P4 is connected to the GND. It also includes a resistor R28 and a resistor R29 connected in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the pin 4 of the optocoupler U4. A light-emitting diode D12 is connected in series on the resistor R28. The pin 4 of the optocoupler U4 is also connected to the Closed State signal through a resistor R33. The pin 3 of the optocoupler U4 is connected to the GND, and the Closed State signal is connected to the pin 73 of the controller.

[0013] Preferably, it further includes an optocoupler U5. Its pin 2 is connected to the pin 2 of P5. Its pin 1 is connected to the 12V VCC through a resistor R42 and the pin 3 of P5 respectively. The pin 1 of P5 is connected to the GND. It also includes a resistor R38 and a resistor R40 connected in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the pin 4 of the optocoupler U5. A light-emitting diode D13 is connected in series on the resistor R38. The pin 4 of the optocoupler U5 is also connected to the power supply status signal through a resistor R43. The pin 3 of the optocoupler U5 is connected to the GND, and the power supply status signal is connected to the pin 31 of the controller.

[0014] Preferably, it further includes a switch SW1 and a switch SW2. Their pin 1s are connected. The pin 2 of the switch SW1 and the pin 2 of the switch SW2 are both connected to the 3.3V VCC. The pin 3 of the switch SW1 is connected to the KEY ON signal, and the pin 3 of the switch SW2 is connected to the KEY OFF signal. The 12V VCC is connected to the CloseState LED signal through a push-button switch with a light. The 5V VCC is connected to the pin 3 of the triode Q7 through a push-button switch with a light. The RUN EN signal is connected to the pin 1 of the triode Q7 after being connected in series with a resistor R39, and the RUN EN signal after being connected in series with the resistor R39 is connected to the GND through a resistor R41. The pin 2 of the triode Q7 is also connected to the GND. The RUN EN signal is connected to the pin 58 of the controller.

[0015] Preferably, it further includes a relay U6. Its pin 2 is connected to the KEY ON signal, its pin 3 is connected to the RLY ON signal, its pin 4 is connected to the OUT ON signal, its pin 5 is connected to the OUT OFF signal, its pin 6 is connected to the RLY OFF signal, and its pin 7 is connected to the KEY OFF signal. The OUT OFF signal and the OUT ON signal are respectively connected to pins 57 and 54 of the controller; the relay U6 and the diode D15 are arranged in parallel. One end of both is connected to the 5V VCC, and the other end and the 5V VCC after connecting the series resistor R44 and the light-emitting diode D14 are both connected to pin 3 of the triode Q8. Pin 1 of the triode Q8 is connected to the OUT EN signal through the resistor R48, and pin 2 of the triode Q8 is connected to the GND. The OUT EN signal after connecting the series resistor R48 is connected to the GND through the resistor R45. The OUT EN signal is connected to pin 43 of the controller.

[0016] Preferably, it further includes a power supply unit composed of a fixed cylinder and an annular turning plate that are hinged to each other. A socket is provided in the fixed cylinder and inclined downward. The annular turning plate is internally provided with a plug-in terminal, and a reset member and a locking member are provided at the hinge. The front of the plug-in terminal is used for plugging in the refrigerated plug, and the back is used for plugging in the socket.

[0017] Preferably, a photoelectric switch for detecting whether the plug-in terminal is plugged in place is vertically provided at the bottom of the fixed cylinder through an extension plate. An open slot for avoiding the photoelectric switch is opened on the bottom plate of the annular turning plate; a rubber expansion sleeve for sealing is provided at the fitting gap between the fixed cylinder and the annular turning plate, and an observation window for visually checking whether the plug-in terminal is plugged in place is also opened on the fixed cylinder.

[0018] Preferably, the locking member includes an installation cylinder sleeved outside the rotating shaft. An angle sensor for detecting the rotation angle of the rotating shaft is provided at the end of the installation cylinder, and a limiting protrusion is additionally installed on the part of the rotating shaft located inside the installation cylinder; a telescopic member is integrated on the installation cylinder, and a limiting block that can laterally penetrate into the installation cylinder is provided at its output end. The limiting block can be inserted into the installation cylinder to lock the limiting protrusion.

[0019] Based on the above technical solutions, by configuring the plug-in terminal and the annular turning plate, a transition structure is constructed between the refrigerated container plug and the inclined socket. It can not only trigger the locking member in case of a failure to achieve mechanical safe detachment and effectively ensure the use safety, but also its power supply posture is set to be inclined, thus ensuring excellent rainwater immersion prevention effect during the power supply process.

[0020] In summary, the present application includes the following beneficial technical effects:

[0021] 1. By setting up the relay control unit, the present invention effectively prevents the relay from disconnecting under the condition of unstable voltage, and improves the stability of the refrigerated container in the powered state;

[0022] 2. By providing the TVS tube 7 in the present invention, the relay circuit can be protected, effectively preventing its main body from being burned out.

[0023] 3. In the present invention, by providing the plug-in terminal and the annular flipping plate, a transition structure is formed between the refrigerated container plug and the diagonal socket, which not only ensures the safety protection that the locking member can be triggered for mechanical detachment during a malfunction, but also makes the power supply posture inclined to ensure the rainproof effect during the power supply process. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the circuit principle of the relay control unit in the present invention Figure 1 ;

[0025] Figure 2 is the circuit schematic diagram of the closed state signal in the present invention;

[0026] Figure 3 is the circuit schematic diagram of the power supply state signal in the present invention;

[0027] Figure 4 is the circuit principle of the relay control unit in the present invention Figure 2 ;

[0028] Figure 5 is the circuit schematic diagram of the PLY ON signal in the present invention;

[0029] Figure 6 is the circuit schematic diagram of the PLY OFF signal in the present invention;

[0030] Figure 7 is the circuit schematic diagram of the relay U6 in the present invention;

[0031] Figure 8 is the circuit schematic diagram of the controller in the present invention;

[0032] Figure 9 is the side view structure schematic diagram of the power supply unit in the present invention;

[0033] Figure 10 is the exploded structure schematic diagram of the power supply unit in the present invention;

[0034] Figure 11 is the right view structure schematic diagram of the power supply unit in the present invention;

[0035] Figure 12 is the structure schematic diagram of the annular flipping plate in the present invention;

[0036] Figure 13 is the exploded structure schematic diagram of the annular flipping plate in the present invention;

[0037] Figure 14It is a schematic cross-sectional view of the annular turning plate structure in the present invention.

[0038] Description of the reference numerals:

[0039] 1. Fixed cylinder, 2. Socket, 3. Extension plate, 4. Photoelectric switch, 5. Plug-in terminal, 6. Annular turning plate, 7. Fitting clearance, 8. Rotating shaft, 9. Reset member, 10. Locking member, 11. Angle sensor

[0040] 101. Observation window, 601. Open slot, 801. Limit projection, 1001. Mounting cylinder, 1002. Telescopic member, 1003. Limit block Specific embodiments

[0041] The following describes the specific embodiments of the present invention in conjunction with the drawings and embodiments:

[0042] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the implementable conditions of the present invention. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention.

[0043] At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of description and clarity, and are not used to limit the implementable scope of the present invention. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the implementable scope of the present invention.

[0044] The following combines the attached Figures 1-14 This application is further described in detail.

[0045] The embodiment of this application discloses a control circuit for a refrigerated container.

[0046] Embodiment 1

[0047] Referring to Figures 1 to 8 , this embodiment discloses a control circuit for a refrigerated container, including a relay control unit composed of a triode Q3 and a triode Q4 arranged in parallel. The emitters of both are respectively connected to the 12V VCC after being serially connected with a resistor R25 and a resistor R24. The base of the triode Q3 is connected to the RLY ON signal through a resistor R30, and the base of the triode Q4 is connected to the RLY OFF signal through a resistor R31;

[0048] The switching triodes Q1 and Q2 are arranged in parallel. The base of the switching triode Q1 is connected to the emitter of the triode Q3 through the resistor R27. The base of the switching triode Q2 is connected to the emitter of the triode Q4 through the resistor R26. And the emitters of the switching triodes Q1 and Q2 are both connected to the 12V VCC.

[0049] The amplifying triodes Q6 and Q5 are arranged in parallel. The collector of the switching triode Q2 is connected to the emitter of the amplifying triode Q5. The collector of the switching triode Q1 is connected to the emitter of the amplifying triode Q6. And a TVS tube 7 is serially connected between the collector of the switching triode Q1 and the emitter of the amplifying triode Q5. The 1st pin of OUT1 is serially connected to the collector of the switching triode Q2. The 2nd pin of OUT1 is serially connected to the collector of the switching triode Q1.

[0050] The bases of the triodes Q3, Q4, amplifying triodes Q6 and Q5 are respectively connected to GND after being serially connected with resistors. And the collectors of the amplifying triodes Q6 and Q5 are directly connected to GND. The collectors of the triodes Q3 and Q4 are connected to GND after being serially connected with the resistors R36 and R35. In this structure, the bases of the triodes Q3, Q4, amplifying triodes Q6 and Q5 are respectively connected to GND after being serially connected with the resistors R37, R34, R35 and R36. In this structure, the resistors R30, R34, R37, R31, R25, R24 are 5.1K - 5%. The resistors R35, R36, R27, R26 are 1K - 5%. The TVS tube 7 is selected as SMBJ30CA. The switching triodes Q1 and Q2 are both selected as MMBT2907A. The triode Q4 is selected as 2SC1623. The amplifying triodes Q8 and Q5 are selected as MMBT2222A. The bases of the triodes Q3, Q4, amplifying triodes Q6 and Q5 are respectively connected to GND after being serially connected with the resistors R37, R34, R35 and R36.

[0051] It also includes an optocoupler U4. Its pin 1 is connected to the 12V VCC through a resistor R32. Its pin 2 is connected to the CloseState LED signal, and its pin 2 is also connected to the pin 1 of P4. The pin 2 of P4 is connected to GND. And it also includes a resistor R28 and a resistor R29 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other ends are both connected to the pin 4 of the optocoupler U4. And a light-emitting diode D12 is connected in series on the resistor R28. The pin 4 of the optocoupler U4 is also connected to the Closed State signal through a resistor R33. The pin 3 of the optocoupler U4 is connected to GND, and the Closed State signal is connected to the 73rd pin of the controller. In this structure, the resistor R32, the resistor R28, and the resistor R33 are selected as 1K - 5%, the resistor R29 is selected as 10K - 5%, and the optocoupler U4 is selected as LTV-214-G.

[0052] It also includes an optocoupler U5. Its pin 2 is connected to the pin 2 of P5. The pin 1 of the optocoupler U5 is connected to the 12V VCC through a resistor R42 and the pin 3 of P5 respectively. And the pin 1 of P5 is connected to GND. And it also includes a resistor R38 and a resistor R40 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other ends are both connected to the pin 4 of the optocoupler U5. And a light-emitting diode D13 is connected in series on the resistor R38. The pin 4 of the optocoupler U5 is also connected to the power supply status signal through a resistor R43. The pin 3 of the optocoupler U5 is connected to GND, and the power supply status signal is connected to the 31st pin of the controller. In this structure, the resistor R43, the resistor R38, and the resistor R42 are selected as 1K - 5%, the resistor R40 is selected as 10K - 5%, and the optocoupler U5 is selected as LTV-214-G.

[0053] It also includes a switch SW1 and a switch SW2. Their pin 1s are connected. The pin 2 of the switch SW1 and the pin 2 of the switch SW2 are both connected to the 3.3V VCC. The pin 3 of the switch SW1 is connected to the KEY ON signal, and the pin 3 of the switch SW2 is connected to the KEY OFF signal. The 12V VCC is connected to the CloseState LED signal through a push-button switch with a light. The 5V VCC is connected to the pin 3 of the triode Q7 through a push-button switch with a light. The RUN EN signal is connected to the pin 1 of the triode Q7 after being connected in series with a resistor R39, and the RUN EN signal after being connected in series with the resistor R39 is connected to GND through a resistor R41. The pin 2 of the triode Q7 is also connected to GND. The RUN EN signal is connected to the 58th pin of the controller. In this structure, the resistor R39 is selected as 1K - 5%, the resistor R41 is selected as 10K - 5%, and the triode Q7 is selected as S8050-J3Y.

[0054] Pin 2 of relay U6 is connected to the KEY ON signal, its pin 3 is connected to the RLY ON signal, its pin 4 is connected to the OUT ON signal, its pin 5 is connected to the OUT OFF signal, its pin 6 is connected to the RLY OFF signal, its pin 7 is connected to the KEY OFF signal. The OUT OFF signal and the OUT ON signal are respectively connected to pins 57 and 54 of the controller. Relay U6 and diode D15 are arranged in parallel. One end of both is connected to the 5V VCC, and the other end and the 5V VCC after series-connected resistor R44 and light-emitting diode D14 are both connected to pin 3 of triode Q8. Pin 1 of triode Q8 is connected to the OUT EN signal through resistor R48, and pin 2 of triode Q8 is connected to GND. The OUT EN signal after series-connected resistor R48 is connected to GND through resistor R45. The OUT EN signal is connected to pin 43 of the controller. In this structure, resistor R44, resistor R48, and resistor R53 are 1K - 5%, resistor R45 is 10K - 5%, diode D15 is selected as M7 - 1N4007, triode Q8 is selected as 8050 - J3Y, and relay U6 is selected as G6K - 2F - Y - 5V.

[0055] The specific principle is as follows: The RLY OFF signal and the RLY ON signal are in parallel, and their control principles are the same. Taking the RLY ON signal as an example; when the RLY ON signal is not introduced, the emitter and base of switching triode Q2 are both 12V. In this state, the collector of switching triode Q2 shows a off signal; when the RLY ON signal is introduced, switching triode Q4 acts to keep the collector of switching triode Q2 showing an on signal.

[0056] Embodiment 2

[0057] Refer to Figure 5 and Figure 6 Based on the above embodiment, this embodiment also discloses a refrigerated container control circuit, which further includes opto - isolator U7 and opto - isolator U8.

[0058] Pin 1 of opto - isolator U7 is connected to the RLY ON signal, its pin 2 is connected to GND through resistor R53, its pin 3 is directly connected to GND, and it also includes resistor R46 and resistor R49 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to pin 4 of opto - isolator U7. And a light - emitting diode D16 is connected in series on resistor R46. Pin 4 of opto - isolator U7 is also connected to the PINT ON signal through resistor R51. The PINT ON signal is connected to pin 41 of the controller. In this structure, resistor R46, resistor R51, and resistor R53 are selected as 1K - 5%, resistor R49 is selected as 10K - 5%, and opto - coupler U7 is selected as LTV - 214 - G.

[0059] The first pin of the opto-isolator U8 is connected to the RLY OFF signal, its second pin is connected to GND through the resistor R54, its third pin is directly connected to GND, and it also includes a parallel arrangement of the resistor R50 and the resistor R47. One end of both is connected to the 3.3V VCC, and the other end is connected to the fourth pin of the opto-isolator U8. A light-emitting diode D17 is connected in series on the resistor R47. The fourth pin of the opto-isolator U8 is also connected to the PINT OFF signal through the resistor R51. The PINT OFF signal is connected to the 42nd pin of the controller. In this structure, the resistors R46, R51, R47, R52, and R53 are 1K - 5%, the resistor R50 is 10K - 5%, the resistor R54 is 10K - 1%, and the opto-coupler U8 is selected as LTV-214-G.

[0060] Embodiment 3

[0061] Referring to Figures 9 to 14 , based on the above embodiments, this embodiment also discloses a control circuit for a refrigerated container, which further includes a power supply unit composed of a fixed cylinder 1 and an annular turning plate 6 that are hinged to each other. A socket 2 is inclined downward in the fixed cylinder 1. An insertion terminal 5 is provided inside the annular turning plate 6, and a reset member 9 and a locking member 10 are provided at the hinge. The front of the insertion terminal 5 is used to insert a refrigeration plug, and the back is used to insert the socket 2. The reset member 9 is a constant-torque structure composed of two rotating cylinders and a coil spring, and any one of the rotating cylinders is coaxially arranged with the hinge.

[0062] A photoelectric switch 4 for detecting whether the insertion terminal 5 is inserted in place is vertically provided at the bottom of the fixed cylinder 1 through an extension plate 3. An open slot 601 for avoiding the photoelectric switch 4 is opened on the bottom plate of the annular turning plate 6. In this structure, a rubber expansion sleeve for sealing is provided at the fitting gap 7 between the fixed cylinder 1 and the annular turning plate 6, and an observation window 101 for visually checking whether the insertion terminal 5 is inserted in place is also opened on the fixed cylinder 1.

[0063] The locking member 10 includes an installation cylinder 1001 sleeved outside the rotating shaft 8. An angle sensor 11 for detecting the rotation angle of the rotating shaft 8 is provided at the end of the installation cylinder 1001, and a limiting protrusion 801 is added to the part of the rotating shaft 8 located inside the installation cylinder 1001. In this structure, a telescopic member 1002 is integrated on the installation cylinder 1001. The telescopic member 1002 is a cylinder structure, and a limiting block 1003 that can laterally penetrate into the installation cylinder 1001 is provided at its output end. The limiting block 1003 can be inserted into the installation cylinder 1001 to lock the limiting protrusion 801.

[0064] The specific implementation process is as follows: In the initial state, the annular turning plate 6 and the plug-in terminal 5 are vertical; insert the plug of the refrigerated container into the plug-in terminal 5; then push the plug-in terminal 5 and the plug of the refrigerated container centered on the rotating shaft 8 to connect the plug-in terminal 5 with the socket 2; at this time, the plug-in terminal 5, the socket 2 and the plug of the refrigerated container are all obliquely arranged relative to the fixed cylinder 1, which can effectively prevent water immersion.

[0065] The angle sensor 11 and the photoelectric switch 4 are electrically connected to the controller. During the rotation of the rotating shaft 8, the angle sensor 11 is triggered to detect the rotation angle of the rotating shaft 8; when the rotating shaft 8 rotates to the plug-in position, the plug-in terminal 5 triggers the photoelectric switch 4 to prove that the plug-in is in place; after the plug-in is in place, the telescopic member 1002 pushes the limit block 1003 into the installation cylinder 1001, and the combination of the limit block 1003 and the limit protrusion 801 prevents the rotating shaft 8 from resetting; if the photoelectric switch 4 is not triggered and the detection angle of the angle sensor 11 is normal, the relay control unit cannot be turned on, and at this time, the photoelectric switch 4 needs to be repaired.

[0066] Many other changes and modifications can be made without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments, and the scope of the present invention is defined by the appended claims.

Claims

1. A refrigerated container control circuit, characterized in that, Comprising: A relay control unit composed of transistors Q3 and Q4 arranged in parallel. The emitters of both are respectively connected in series with resistors R25 and R24 and then connected to the 12V VCC. The base of transistor Q3 is connected to the RLY ON signal through resistor R30, and the base of transistor Q4 is connected to the RLY OFF signal through resistor R31; Switched transistors Q1 and Q2 arranged in parallel. The base of switched transistor Q1 is connected to the emitter of transistor Q3 through resistor R27, the base of switched transistor Q2 is connected to the emitter of transistor Q4 through resistor R26, and the emitters of both switched transistors Q1 and Q2 are connected to the 12V VCC; Amplifying transistors Q6 and Q5 arranged in parallel. The collector of switched transistor Q2 is connected to the emitter of amplifying transistor Q5, the collector of switched transistor Q1 is connected to the emitter of amplifying transistor Q6, and a TVS diode 7 is connected in series between the collector of switched transistor Q1 and the emitter of amplifying transistor Q5. The 1st pin of OUT1 is connected in series on the collector of switched transistor Q2, and the 2nd pin of OUT1 is connected in series on the collector of switched transistor Q1; The bases of transistors Q3, Q4, amplifying transistors Q6 and Q5 are respectively connected to GND through series resistors, and the collectors of amplifying transistors Q6 and Q5 are directly connected to GND. The collectors of transistors Q3 and Q4 are connected to GND through series resistors R36 and R35. The relay control unit effectively prevents the disconnection of the relay under the condition of unstable voltage based on the principle of magnetic holding. The TVS diode 7 is used for circuit protection and anti-burning; It further includes an opto-isolator U7, whose 1st pin is connected to the RLY ON signal, its 2nd pin is connected to GND through resistor R53, and its 3rd pin is directly connected to GND; It further includes resistors R46 and R49 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the 4th pin of the opto-isolator U7. A light-emitting diode D16 is connected in series on resistor R46. The 4th pin of the opto-isolator U7 is also connected to the PINT ON signal through resistor R51, and the PINT ON signal is connected to the 41st pin of the controller.

2. The control circuit of a refrigerated container according to claim 1, wherein It further includes an opto-isolator U8, whose 1st pin is connected to the RLY OFF signal, its 2nd pin is connected to GND through resistor R54, and its 3rd pin is directly connected to GND; It further includes resistors R50 and R47 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end is connected to the 4th pin of the opto-isolator U8. A light-emitting diode D17 is connected in series on resistor R47. The 4th pin of the opto-isolator U8 is also connected to the PINT OFF signal through resistor R51, and the PINT OFF signal is connected to the 42nd pin of the controller.

3. The control circuit of a refrigerated container according to claim 1, characterized in that, It further includes an opto-coupler U4, whose 1st pin is connected to the 12V VCC through resistor R32, its 2nd pin is connected to the CloseState LED signal, and its 2nd pin is also connected to the 1st pin of P4. The 2nd pin of P4 is connected to GND; It also includes a resistor R28 and a resistor R29 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end of both is connected to the 4th pin of the optocoupler U4. A light-emitting diode D12 is connected in series on the resistor R28. The 4th pin of the optocoupler U4 is also connected to the Closed State signal through a resistor R33. The 3rd pin of the optocoupler U4 is connected to the GND, and the Closed State signal is connected to the 73rd pin of the controller.

4. The control circuit of a refrigerated container according to claim 1, characterized in that It also includes an optocoupler U5. Its 2nd pin is connected to the 2nd pin of P5. The 1st pin of the optocoupler U5 is connected to the 12V VCC through a resistor R42 and the 3rd pin of P5 respectively. And the 1st pin of P5 is connected to the GND; It also includes a resistor R38 and a resistor R40 arranged in parallel. One end of both is connected to the 3.3V VCC, and the other end of both is connected to the 4th pin of the optocoupler U5. A light-emitting diode D13 is connected in series on the resistor R38. The 4th pin of the optocoupler U5 is also connected to the power supply state signal through a resistor R43. The 3rd pin of the optocoupler U5 is connected to the GND, and the power supply state signal is connected to the 31st pin of the controller.

5. The control circuit of a refrigerated container according to claim 1, characterized in that, It also includes a switch SW1 and a switch SW2. Their 1st pins are connected. The 2nd pin of the switch SW1 and the 2nd pin of the switch SW2 are both connected to the 3.3V VCC. The 3rd pin of the switch SW1 is connected to the KEY ON signal, and the 3rd pin of the switch SW2 is connected to the KEY OFF signal; The 12V VCC is connected to the CloseState LED signal through a push-button switch with a light. The 5V VCC is connected to the 3rd pin of the triode Q7 through a push-button switch with a light. The RUN EN signal is connected in series with a resistor R39 and then connected to the 1st pin of the triode Q7. And the RUN EN signal after being connected in series with the resistor R39 is connected to the GND through a resistor R41. The 2nd pin of the triode Q7 is also connected to the GND. The RUN EN signal is connected to the 58th pin of the controller.

6. The control circuit of a refrigerated container according to claim 1, characterized in that, It also includes a relay U6. Its 2nd pin is connected to the KEY ON signal, its 3rd pin is connected to the RLY ON signal, its 4th pin is connected to the OUT ON signal, its 5th pin is connected to the OUT OFF signal, its 6th pin is connected to the RLY OFF signal, its 7th pin is connected to the KEY OFF signal. The OUT OFF signal and the OUT ON signal are respectively connected to the 57th pin and the 54th pin of the controller; The relay U6 and the diode D15 are arranged in parallel. One end of both is connected to the 5V VCC, and the other end and the 5V VCC after being connected in series with a resistor R44 and a light-emitting diode D14 are both connected to the 3rd pin of the triode Q8. The 1st pin of the triode Q8 is connected to the OUT EN signal through a resistor R48. And the 2nd pin of the triode Q8 is connected to the GND. The OUT EN signal after being connected in series with the resistor R48 is connected to the GND through a resistor R45. The OUT EN signal is connected to the 43rd pin of the controller.

7. The control circuit of a refrigerated container according to claim 1, characterized in that, It also includes a power supply unit composed of a fixed cylinder (1) and an annular turning plate (6) that are hinged to each other. A socket (2) is provided in the fixed cylinder (1) and inclined downward. An insertion terminal (5) is built in the annular turning plate (6), and a reset member (9) and a locking member (10) are provided at the hinge. The front of the insertion terminal (5) is used for plugging in a refrigeration plug, and the back is used for plugging into the socket (2).

8. The control circuit of a refrigerated container according to claim 7, wherein A photoelectric switch (4) for detecting whether the insertion terminal (5) is plugged in place is vertically provided at the bottom of the fixed cylinder (1) through an extension plate (3). An open slot (601) for avoiding the photoelectric switch (4) is opened on the bottom plate of the annular turning plate (6); A rubber expansion sleeve for sealing is provided at the mating gap (7) between the fixed cylinder (1) and the annular turning plate (6), and an observation window (101) for visually inspecting whether the insertion terminal (5) is plugged in place is also opened on the fixed cylinder (1).

9. The control circuit of a refrigerated container according to claim 8, characterized in that, The locking member (10) includes a mounting cylinder (1001) sleeved outside the rotating shaft (8). An angle sensor (11) for detecting the rotation angle of the rotating shaft (8) is provided at the end of the mounting cylinder (1001), and a limiting protrusion (801) is added to the part of the rotating shaft (8) located inside the mounting cylinder (1001); A telescopic member (1002) is integrated on the mounting cylinder (1001), and a limiting block (1003) that can laterally penetrate into the mounting cylinder (1001) is provided at its output end. The limiting block (1003) can be inserted into the mounting cylinder (1001) to lock the limiting protrusion (801).

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