Electric forklift air conditioning system with multiple protections

Abstract

The utility model discloses a kind of electric fork-lift truck air conditioning systems with multiple protection, specifically electric fork-lift truck electrical control technical field, comprising: air conditioner compressor, air conditioner fan and control module;Control module includes: system power-on management module, for receiving power-on signal, and after delaying a preset time, the start signal is passed to air conditioner compressor;And, over-temperature protection module, for by sensing temperature change to break and make air conditioner compressor's power supply circuit;System power-on management module includes: power module, switch module, fork-lift truck controller, fork-lift truck controller precharge circuit, DC-DC converter and air conditioner power-on delay timer.The utility model utilizes fork-lift truck controller precharge circuit to complete precharge process;Utilize air conditioner power-on delay timer to delay the power-on of air conditioner compressor, the start time of air conditioner compressor and fork-lift truck controller is staggered, fundamentally avoid the battery voltage sudden drop caused by air conditioner compressor large current impact.

Description

Technical Field

[0001] This utility model relates to the field of electrical control technology for electric forklifts, and more specifically, to an air conditioning system for electric forklifts with multiple protections. Background Technology

[0002] With the widespread application of electric forklifts in warehousing and logistics, driving comfort has become a key concern for users, and air conditioning systems are gradually becoming standard equipment. The compressor in an electric forklift's air conditioning system draws 3-5 times its rated current upon startup, making it a typical high-power load. When the ignition switch is closed, if the air conditioning compressor, forklift controller, steering system, and other core components are simultaneously powered on, it can easily cause a momentary drop in battery voltage, potentially leading to controller restarts, steering system malfunctions, and other failures, severely impacting the forklift's operational safety and efficiency.

[0003] Therefore, in order to solve the problem of system failure caused by the large current surge due to the simultaneous power-on of the electric forklift's air conditioning compressor and core control system, this utility model proposes an electric forklift air conditioning system with multiple protections as a further improvement. Utility Model Content

[0004] In order to overcome the above-mentioned defects of the prior art, the embodiments of this utility model provide an electric forklift air conditioning system with multiple protections to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: an electric forklift air conditioning system with multiple protections, comprising: an air conditioning compressor, an air conditioning fan, and a control module; the control module includes: The system power-on management module receives power-on signals and, after a preset delay, transmits a start signal to the air conditioning compressor; and, An over-temperature protection module that switches the power supply circuit of the air conditioner compressor on or off by sensing temperature changes; The system power-on management module includes: a power module, a switch module, a forklift controller, a forklift controller pre-charging circuit, a DC-DC converter, and an air conditioner power-on delay unit; The power module is connected to the forklift controller via a forklift controller contactor and a forklift controller pre-charging circuit. The power module is connected to the over-temperature protection module via a DC-DC converter. The over-temperature protection module is also connected to the air conditioner power-on delay unit and the air conditioner fan. The air conditioner power-on delay unit is connected to the air conditioner compressor via an air conditioner compressor contactor. The power module is connected to the air conditioner compressor via an air conditioner compressor contactor. The power module is connected to the DC-DC converter and the forklift controller via a switch module.

[0006] Furthermore, the positive terminal of the power module is connected to one end of the forklift controller contactor and the input terminal of the forklift controller pre-charging circuit, respectively. The other end of the forklift controller contactor and the output terminal of the forklift controller pre-charging circuit are both connected to the positive power terminal B+ of the forklift controller. The negative power terminal B- of the forklift controller is connected to the negative terminal of the power module.

[0007] Furthermore, the pre-charging circuit of the forklift controller includes a diode and a resistor, the positive terminal of the power module is connected to the anode of the diode, and the cathode of the diode is connected to the positive terminal B+ of the power supply of the forklift controller through the resistor.

[0008] Furthermore, the positive terminal of the power module is connected to the IN terminal of the DC-DC converter, the power output terminal OUT of the DC-DC converter is connected to the input terminal of the over-temperature protection module, the output terminal of the over-temperature protection module is connected to the positive terminal of the air conditioner fan, and the negative terminal of the air conditioner fan and the negative power terminal B- of the DC-DC converter are both connected to the negative terminal of the power module.

[0009] Furthermore, the output terminal of the over-temperature protection module is connected to the air conditioner power-on delay timer, and the input and output terminals of the air conditioner power-on delay timer are respectively electrically connected to the two ends of the electromagnetic coil of the air conditioner compressor contactor. The electromagnetic coil of the air conditioner compressor contactor is used to control the opening and closing of the main contacts of the air conditioner compressor contactor. The positive terminal of the power module is connected to the air conditioner compressor through the main contact of the air conditioner compressor contactor, and the negative terminal of the air conditioner compressor is connected to the negative terminal of the power module.

[0010] Furthermore, the switch module includes: an emergency stop switch and a key switch; The positive terminal of the power module is connected to one end of the emergency stop switch, the other end of the emergency stop switch is connected to one end of the key switch, and the other end of the key switch is connected to the enable terminal C of the DC-DC converter and the KEY signal terminal of the forklift controller.

[0011] Furthermore, the system power-on management module also includes: a first fuse and a second fuse; The positive terminal of the power module is connected to the IN terminal of the DC-DC converter via the first fuse; The positive terminal of the power module is connected to one end of the emergency stop switch via a second fuse.

[0012] Furthermore, the over-temperature protection module is configured as an air conditioning temperature control protector.

[0013] Furthermore, the safety threshold of the over-temperature protection module is set to ≤60℃.

[0014] Furthermore, the power of the air conditioner compressor is ≥500W.

[0015] The technical effects and advantages of this utility model are as follows: 1. Compared with existing technologies, the pre-charging process is completed using the pre-charging circuit of the forklift controller; the power-on delay timer of the air conditioner compressor is used to delay the power-on of the air conditioner compressor, thus staggering the start-up time of the air conditioner compressor and the forklift controller, fundamentally avoiding the sudden drop in battery voltage caused by the large current surge of the air conditioner compressor; that is, when supplying power to the air conditioner compressor, this circuit can gradually and smoothly increase the drive voltage to the rated value, rather than applying full voltage instantaneously; thereby further suppressing the peak value of the starting current and realizing dual current protection; directly solving the fatal faults such as controller restart and steering failure mentioned in the background technology, ensuring the stability and safety of the forklift at the moment of start-up.

[0016] 2. Compared with existing technologies, by setting up an over-temperature protection module to monitor the temperature of key components in real time, the power supply can be cut off in time when the air conditioning compressor or other air conditioning systems are about to overheat due to high temperature environment, excessive load, etc., effectively preventing the core components from burning out due to overheating and significantly extending the service life of the forklift air conditioning system; in conjunction with the air conditioning power-on delay device, multiple protections are finally achieved for the electric forklift air conditioning system. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the electrical structure of this utility model.

[0018] The attached diagram is labeled as follows: 100, Air conditioning compressor; 200, Air conditioning fan; 300, Control module; 310, System power-on management module; 311, Power supply module; 312, Switch module; 313, Forklift controller; 314, Forklift controller pre-charging circuit; 315, DC-DC converter; 316, Air conditioning power-on delay timer; 317, Forklift controller contactor; 318, Air conditioning compressor contactor; 320, Over-temperature protection module; ES, Emergency Stop Switch; KEY, Key Switch; F1, First Fuse; F2, Second Fuse. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0020] As attached Figure 1 The electric forklift air conditioning system shown includes: an air conditioning compressor 100, an air conditioning fan 200, and a control module 300; the control module 300 includes: The system power-on management module 310 is used to receive the power-on signal and transmit the start signal to the air conditioning compressor 100 after a preset delay. as well as, Over-temperature protection module 320, which switches the power supply circuit of air conditioner compressor 100 by sensing temperature changes; The system power-on management module 310 includes: a power module 311, a switch module 312, a forklift controller 313, a forklift controller pre-charging circuit 314, a DC-DC converter 315, and an air conditioner power-on delay unit 316; The power module 311 is connected to the forklift controller 313 via the forklift controller contactor 317 and the forklift controller pre-charging circuit 314, respectively. The power module 311 is connected to the over-temperature protection module 320 via the DC-DC converter 315. The over-temperature protection module 320 is also connected to the air conditioner power-on delay unit 316 and the air conditioner fan 200, respectively. The air conditioner power-on delay unit 316 is connected to the air conditioner compressor 100 via the air conditioner compressor contactor 318. The power module 311 is connected to the air conditioner compressor 100 via the air conditioner compressor contactor 318. The power module 311 is connected to the DC-DC converter 315 and the forklift controller 313 via the switch module 312, respectively.

[0021] Among them, protection method one: the pre-charging process is completed by using the pre-charging circuit 314 of the forklift controller; The power module 311 slowly charges the internal capacitor of the forklift controller 313 through the forklift controller pre-charging circuit 314. The forklift controller pre-charging circuit 314 directly charges the internal capacitor of the forklift controller 313 slowly, completing the pre-charging process. At this time, it will be difficult for a large current surge to occur after the forklift controller contactor 317 is closed. Protection method two: Delay the power-on of the air conditioner compressor 100 using the air conditioner power-on delay timer 316; The power module 311 provides input power to the DC-DC converter 315, and the power module 311 sends a power-on signal to the DC-DC converter 315 through the switch module 312. The system power-on management module 310 receives the power-on signal. The DC-DC converter 315 is powered on and outputs low-voltage power to supply power to the air conditioner power-on delay timer 316 through the temperature protection module 320. At this time, the air conditioner power-on delay timer 316 transmits the start signal to the air conditioner compressor contactor 318 after a preset time delay. The air conditioner compressor contactor 318 closes to supply power to the air conditioner compressor 100, and the air conditioner compressor 100 is powered on and starts working.

[0022] Protection method three: Use the over-temperature protection module 320 to prevent component damage; If an abnormality such as blocked air outlet or poor condenser heat dissipation causes the air conditioner compressor 100 to overheat, for example, if the over-temperature protection module 320 senses a temperature exceeding 85°C, the over-temperature protection module 320 will automatically disconnect, cutting off the power supply to the air conditioner power-on delay timer 316, thereby de-energizing and disconnecting the air conditioner compressor contactor 318, and the air conditioner compressor 100 will stop working; once the temperature drops to a safe threshold, for example, if the over-temperature protection module 320 senses a temperature ≤60°C, the over-temperature protection module 320 will automatically reset, and the system will resume operation according to the above sequence to prevent component damage.

[0023] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the positive terminal of the power module 311 is connected to one end of the forklift controller contactor 317 and the input terminal of the forklift controller pre-charging circuit 314, respectively. The other end of the forklift controller contactor 317 and the output terminal of the forklift controller pre-charging circuit 314 are both connected to the positive power terminal B+ of the forklift controller 313. The negative power terminal B- of the forklift controller 313 is connected to the negative terminal of the power module 311. Specifically, the forklift controller 313 is precharged using the forklift controller pre-charging circuit 314 to avoid the forklift controller 313 and the air conditioning compressor 100 being powered on at the same time, thereby avoiding the large current generated when the air conditioning compressor 100 is powered on from impacting the forklift controller 313 and reducing the risk of system failure.

[0024] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the forklift controller pre-charging circuit 314 includes a diode and a resistor. The positive terminal of the power module 311 is connected to the anode of the diode, and the cathode of the diode is connected to the positive terminal B+ of the power supply of the forklift controller 313 through the resistor. By utilizing the unidirectional conductivity of the diode, the power module 311 is ensured to bypass the forklift controller contactor 317 to pre-charge the forklift controller 313.

[0025] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the positive terminal of the power module 311 is connected to the IN terminal of the DC-DC converter 315, the power output terminal OUT of the DC-DC converter 315 is connected to the input terminal of the over-temperature protection module 320, the output terminal of the over-temperature protection module 320 is connected to the positive terminal of the air conditioner fan 200, and the negative terminal of the air conditioner fan 200 and the negative power terminal B- of the DC-DC converter 315 are both connected to the negative terminal of the power module 311; so that the temperature sensor of the over-temperature protection module 320 can be used to monitor and protect the temperature, and prevent the air conditioner compressor 100 from overheating and being damaged due to long-term high-load operation.

[0026] In a preferred embodiment, as shown in the appendix Figure 1As shown, the output terminal of the over-temperature protection module 320 is connected to the air conditioner power-on delay unit 316. The input and output terminals of the air conditioner power-on delay unit 316 are electrically connected to the two ends of the electromagnetic coil of the air conditioner compressor contactor 318, respectively. The electromagnetic coil of the air conditioner compressor contactor 318 is used to control the opening and closing of the main contacts of the air conditioner compressor contactor 318. The positive terminal of the power supply module 311 is connected to the air conditioner compressor 100 through the main contacts of the air conditioner compressor contactor 318, and the negative terminal of the air conditioner compressor 100 is connected to the negative terminal of the power supply module 311. This is to delay the power-on of the air conditioner compressor 100 using the air conditioner power-on delay unit 316. In a preferred embodiment, as shown in the appendix Figure 1 As shown, the switch module 312 includes: an emergency stop switch ES and a key switch KEY; The positive terminal of the power module 311 is connected to one end of the emergency stop switch ES, the other end of the emergency stop switch ES is connected to one end of the key switch KEY, and the other end of the key switch KEY is connected to the enable terminal C of the DC-DC converter 315 and the KEY signal terminal of the forklift controller 313.

[0027] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the system power-on management module 310 also includes: a first fuse F1 and a second fuse F2; The positive terminal of the power module 311 is connected to the IN terminal of the DC-DC converter 315 through the first fuse F1; the positive terminal of the power module 311 is connected to one end of the emergency stop switch ES through the second fuse F2, so as to protect the circuit using the first fuse F1 and the second fuse F2.

[0028] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the over-temperature protection module 320 is configured as an air conditioning temperature control protector.

[0029] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the safety threshold of the over-temperature protection module 320 is set to ≤60℃; so that when the air conditioner compressor 100 overheats due to abnormalities such as blocked air outlet or poor condenser heat dissipation, the over-temperature protection module 320 can automatically disconnect, cut off the power supply to the air conditioner power-on delay timer 316, thereby de-energizing and disconnecting the air conditioner compressor contactor 318, and stopping the air conditioner compressor 100 from working; it will automatically reset when the temperature drops to the safety threshold to prevent component damage.

[0030] In a preferred embodiment, as shown in the appendix Figure 1 As shown, the power of the air conditioner compressor 100 is ≥500W.

[0031] Working principle of this utility model: If the emergency stop switch ES and the key switch KEY of the vehicle are disconnected, the power module 311 provides input power to the DC-DC converter 315 through the main circuit. However, because the key switch KEY is disconnected, the power output terminal OUT of the DC-DC converter 315 has no output voltage. At the same time, the power module 311 slowly charges the internal capacitor of the forklift controller 313 through the forklift controller pre-charging circuit 314 to complete the pre-charging process and avoid a large current surge when the forklift controller contactor 317 is closed later.

[0032] If the emergency stop switch ES and the key switch KEY are closed, the vehicle enters the power-on process after the key switch KEY is closed. This means the KEY signal terminal of the forklift controller 313 is energized, triggering the internal logic of the forklift controller 313. Within 2 seconds, the forklift controller 313 outputs a control signal to engage the forklift controller contactor 317, thus activating the main circuit of the forklift controller 313 and entering the working state. Simultaneously, the enable terminal C of the DC-DC converter 315 is energized and starts, stably outputting low-voltage power from the power output terminal OUT to power the low-voltage components of the electric forklift's air conditioning system. At this time, the DC-DC converter... After the converter 315 outputs low-voltage power, it directly drives the air conditioner fan 200 to start via the over-temperature protection module 320. The impact on the overall vehicle voltage is negligible, achieving ventilation or heat dissipation preparation. Simultaneously, the low-voltage power output from the DC-DC converter 315 is also transmitted to the air conditioner power-on delay unit 316 via the over-temperature protection module 320. This power-on delay unit 316 is set with a 3.5-second trigger time (starting from the output of the DC-DC converter 315). After 3.5 seconds, the power-on delay unit 316 outputs a signal to engage the air conditioner compressor contactor 318, thus energizing the air conditioner compressor 100. At this point, a 1.5-second delay has occurred compared to the forklift controller 313's power-on, completely avoiding the peak load of this core component's power-on, preventing the risk of the 48V battery voltage being pulled low, and ensuring the stable operation of the vehicle's forklift controller 313 and DC-DC converter 315.

[0033] If an abnormality such as blocked air outlet or poor condenser heat dissipation causes the air conditioner compressor 100 to overheat, for example, if the over-temperature protection module 320 senses a temperature exceeding 85°C, the over-temperature protection module 320 will automatically disconnect, cutting off the power supply to the air conditioner power-on delay timer 316, thereby de-energizing and disconnecting the air conditioner compressor contactor 318, and the air conditioner compressor 100 will stop working; once the temperature drops to a safe threshold, for example, if the over-temperature protection module 320 senses a temperature ≤60°C, the over-temperature protection module 320 will automatically reset, and the system will resume operation according to the above sequence to prevent component damage.

[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An air conditioning system for an electric forklift with multiple protections, comprising: An air conditioning compressor (100), an air conditioning fan (200), and a control module (300); characterized in that the control module (300) comprises: The system power-on management module (310) receives a power-on signal and, after a preset delay, transmits a start signal to the air conditioning compressor (100); and, An over-temperature protection module (320) is provided, which switches the power supply circuit of the air conditioning compressor (100) on or off by sensing temperature changes; The system power-on management module (310) includes: a power module (311), a switch module (312), a forklift controller (313), a forklift controller pre-charging circuit (314), a DC-DC converter (315), and an air conditioner power-on delay device (316). The power module (311) is connected to the forklift controller (313) via the forklift controller contactor (317) and the forklift controller pre-charging circuit (314); the power module (311) is connected to the over-temperature protection module (320) via the DC-DC converter (315), and the over-temperature protection module (320) is also connected to the air conditioner power-on delay device (316) and the air conditioner fan (200) respectively; the air conditioner power-on delay device (316) is connected to the air conditioner compressor (100) via the air conditioner compressor contactor (318); the power module (311) is connected to the air conditioner compressor (100) via the air conditioner compressor contactor (318); the power module (311) is connected to the DC-DC converter (315) and the forklift controller (313) via the switch module (312).

2. The electric forklift air conditioning system with multiple protections according to claim 1, characterized in that: The positive terminal of the power module (311) is connected to one end of the forklift controller contactor (317) and the input terminal of the forklift controller pre-charging circuit (314), respectively. The other end of the forklift controller contactor (317) and the output terminal of the forklift controller pre-charging circuit (314) are both connected to the positive power terminal B+ of the forklift controller (313). The negative power terminal B- of the forklift controller (313) is connected to the negative terminal of the power module (311).

3. The electric forklift air conditioning system with multiple protections according to claim 2, characterized in that: The forklift controller pre-charging circuit (314) includes a diode and a resistor. The positive terminal of the power module (311) is connected to the anode of the diode, and the cathode of the diode is connected to the positive terminal B+ of the power supply of the forklift controller (313) through the resistor.

4. The electric forklift air conditioning system with multiple protections according to claim 1, characterized in that: The positive terminal of the power module (311) is connected to the IN terminal of the DC-DC converter (315). The power output terminal OUT of the DC-DC converter (315) is connected to the input terminal of the over-temperature protection module (320). The output terminal of the over-temperature protection module (320) is connected to the positive terminal of the air conditioner fan (200). The negative terminal of the air conditioner fan (200) and the negative power terminal B- of the DC-DC converter (315) are both connected to the negative terminal of the power module (311).

5. The electric forklift air conditioning system with multiple protections according to claim 4, characterized in that: The output terminal of the over-temperature protection module (320) is connected to the air conditioner power-on delay device (316). The input and output terminals of the air conditioner power-on delay device (316) are electrically connected to the two ends of the electromagnetic coil of the air conditioner compressor contactor (318). The electromagnetic coil of the air conditioner compressor contactor (318) is used to control the opening and closing of the main contacts of the air conditioner compressor contactor (318). The positive terminal of the power module (311) is connected to the air conditioner compressor (100) through the main contact of the air conditioner compressor contactor (318), and the negative terminal of the air conditioner compressor (100) is connected to the negative terminal of the power module (311).

6. The electric forklift air conditioning system with multiple protections according to claim 1, characterized in that: The switch module (312) includes: an emergency stop switch (ES) and a key switch (KEY); The positive terminal of the power module (311) is connected to one end of the emergency stop switch (ES), the other end of the emergency stop switch (ES) is connected to one end of the key switch (KEY), and the other end of the key switch (KEY) is connected to the enable terminal C of the DC-DC converter (315) and the KEY signal terminal of the forklift controller (313).

7. An electric forklift air conditioning system with multiple protections according to claim 4 or 6, characterized in that: The system power-on management module (310) also includes: a first fuse (F1) and a second fuse (F2); The positive terminal of the power module (311) is connected to the IN terminal of the DC-DC converter (315) through the first fuse (F1); The positive terminal of the power module (311) is connected to one end of the emergency stop switch (ES) via the second fuse (F2).

8. The electric forklift air conditioning system with multiple protections according to claim 5, characterized in that: The over-temperature protection module (320) is configured as an air conditioning temperature control protector.

9. An electric forklift air conditioning system with multiple protections according to claim 8, characterized in that: The safety threshold of the over-temperature protection module (320) is set to ≤60℃.

10. An electric forklift air conditioning system with multiple protections according to claim 5, characterized in that: The power of the air conditioner compressor (100) is ≥500W.

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