Operator protection system for high-voltage distribution box and engineering machinery

Abstract

The utility model provides an operator protection system for a high-voltage distribution box and engineering machinery. The high-voltage distribution box comprises a shell (1), wherein the shell is provided with at least one side wall (11) and is internally provided with positive and negative connection ends (12 and 13) connected with a power supply. The operator protection system comprises a first detection device (3), the first detection device comprises a detection connecting piece (31) arranged at a first installation position (112) of the side wall, and the detection connecting piece is electrically connected with the positive electrode connecting end and the negative electrode connecting end respectively and can be connected with an external electrical measuring instrument. According to the operator protection system disclosed by the invention, an operator can know the voltage condition in the high-voltage distribution box in time, and the risk that the operator is damaged by residual voltage when the high-voltage distribution box is maintained is avoided.

Description

Technical Field

[0001] The present disclosure relates to a high voltage distribution box, and more particularly to a high voltage distribution box for electric engineering machinery. More specifically, the present disclosure relates to an operator protection system for providing safety protection for maintenance personnel of the high voltage distribution box. Background Art

[0002] With the popularization of electrification of passenger cars and commercial vehicles, vehicles such as construction machinery and mining machinery are also being electrified, and pure electric construction machinery has been launched one after another. As the distribution unit in electric vehicles, the high-voltage distribution box distributes the high-voltage electricity of the power battery to high-voltage electrical equipment such as motor controllers, drive motors, air-conditioning compressors, and PTC heaters, and distributes the high-voltage charging current of the AC and DC charging interfaces to the power battery in order to reverse charge the power battery.

[0003] High-voltage distribution boxes are usually equipped with contactors, which are responsible for controlling the on and off of the main circuit or branch circuit. However, sometimes due to contactor failure, although the controller gives the contactor an opening command, the contactor remains closed, resulting in the presence of high voltage electricity inside the high-voltage distribution box. On the other hand, some electrical equipment external to the high-voltage distribution box, such as motor controllers and fans, contain large capacitors. After these electrical equipment are actively powered off, the internal capacitors will generate reverse residual high voltage in the main circuit at the moment of power failure. Both of these situations will bring serious safety risks to operators repairing high-voltage distribution boxes. Utility Model Content

[0004] The present disclosure aims to solve one or more problems in the above-mentioned prior art and proposes a solution that can avoid contact with high voltage electricity before an operator repairs a high-voltage distribution box.

[0005] Specifically, the present disclosure provides an operator protection system for a high-voltage distribution box, the high-voltage distribution box comprising a housing, the housing comprising at least one side wall, and a positive connection terminal and a negative connection terminal intended to be connected to the positive and negative electrodes of a power source, respectively, are arranged in the housing, the operator protection system comprises a first detection device, the first detection device comprises a detection connector arranged at a first mounting position of the side wall, the detection connector is electrically connected to the positive connection terminal and the negative connection terminal, respectively, and is configured to be connected to an external electrical measuring instrument. In this way, the first detection device can be used as a detection port to allow the voltage value, especially the residual voltage value, in the high-voltage distribution box to be detected and known by means of an external electrical measuring instrument.

[0006] The operator protection system disclosed in the present invention allows the operator to measure the voltage value between the positive connection terminal and the negative connection terminal of the main circuit in the high-voltage distribution box by connecting an external electrical measuring instrument to the first detection device before opening the high-voltage distribution box for maintenance or repair, thereby clearly knowing the residual voltage in the high-voltage distribution box, avoiding the serious safety risk of harm to the operator due to reverse charging caused by large capacitors in external electrical equipment or residual high voltage caused by contactor failure in the high-voltage distribution box.

[0007] In another aspect, the present disclosure relates to a construction machine including a high-voltage distribution box and an operator protection system for the high-voltage distribution box as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The details and advantages of the present disclosure may be understood through the following description with reference to the accompanying drawings and in combination with specific embodiments. In the accompanying drawings:

[0009] Figure 1 is a perspective view of an exemplary high voltage distribution box equipped with an operator protection system according to a preferred embodiment of the present disclosure;

[0010] Figure 2 yes Figure 1 The three-dimensional diagram of the high-voltage distribution box shown is after removing the metal cover and the transparent cover;

[0011] Figure 3 Shown on an enlarged scale Figure 2 Detail A of

[0012] Figure 4 It is a schematic diagram of the principle of the first detection device. DETAILED DESCRIPTION

[0013] The technical solution of the present disclosure is further specifically described below through embodiments and in conjunction with the accompanying drawings. The description is intended to explain the overall concept of the present disclosure and should not be construed as limiting the present disclosure.

[0014] The high-voltage distribution box involved in the present disclosure can be applied to electric vehicles or electric engineering machinery driven by new energy such as lithium batteries, and is particularly applicable to electric loaders, electric excavators, etc. Figure 2 As shown, the high-voltage distribution box of the electric engineering machinery may include a housing 1. The housing 1 may include a bottom wall and at least one (especially four) side walls 11 connected to the periphery of the bottom wall, thereby jointly defining a cavity structure with an open top. The cavity structure may be closed at the top by a metal cover plate 4, so that a sealed internal space is formed in the housing 1.

[0015] The housing 1 may be provided with a positive connection terminal 12 and a negative connection terminal 13 for connecting the positive and negative electrodes of the power source, respectively, and a plurality of power distribution modules connected between the positive connection terminal 12 and the negative connection terminal 13, so that the high voltage electricity of the power source is distributed to the motor controller, the drive motor, the air conditioning compressor, the PTC heater and other high voltage electrical equipment through the plurality of power distribution modules. To this end, various ports or lead wires may be provided on each side wall 11 for connecting various electrical equipment.

[0016] Furthermore, if Figure 2 As shown, the positive electrode connection terminal 12 and the negative electrode connection terminal 13 in the high-voltage distribution box can be in the form of two parallel copper bars. The two copper bars can be connected in series with a contactor and an optional fuse, etc., so as to form a main circuit when the high-voltage distribution box is connected to a power source. In this way, compared with the copper wires of the prior art, the current carrying capacity of the positive and negative electrodes can be increased, which is particularly suitable for the power supply of electric engineering machinery, which is usually up to 850V.

[0017] See also Figure 1 The operator protection system of the present disclosure may include a first detection device 3 and a second detection device 2 arranged on a high-voltage distribution box. The first detection device 3 and the second detection device 2 may both include a portion capable of detecting the voltage in the high-voltage distribution box and, in particular, a portion of the main circuit voltage between the positive and negative connection terminals 12, 13 directly connected to the power supply, and a portion that can be touched by the operator so as to know the voltage they detect.

[0018] Specifically, see Figure 2 Combined with Figure 1 The second detection device 2 may include a high voltage indicator 21 disposed at a second mounting position 111 of the housing 1, the high voltage indicator 21 may be electrically connected to the positive electrode connection terminal 12 and the negative electrode connection terminal 13 in the form of a copper busbar through a first wire 22 and a second wire 23, respectively, and is configured to emit a visual signal when the voltage between the positive electrode connection terminal 12 and the negative electrode connection terminal 13 is higher than a set voltage value. Advantageously, the second mounting position 111 is positioned on one side wall 11.

[0019] The first detection device 3 may include a detection connector 31 disposed at a first mounting position 112 of the housing 1, the detection connector 31 may be electrically connected to the positive electrode connection terminal 12 and the negative electrode connection terminal 13, respectively, and is configured to be connected to an external electrical measuring instrument, such as a multimeter, etc. Advantageously, the first mounting position 112 is positioned on the other side wall 11.

[0020] It should be pointed out here that although Figure 1In the illustrated embodiment, the first mounting position 112 and the second mounting position 111 are respectively positioned on different side walls 11 of the housing 1 , but it is also conceivable that the two mounting positions are positioned on the same side wall.

[0021] according to Figure 2 In the preferred embodiment shown, the high voltage indicator 21 may include a connector for connecting a high voltage indicator light (not shown). The connector may be inserted into a second mounting seat or a second mounting hole 1111 provided at a second mounting position 111, and partially extend into the housing 1 so that its positive and negative electrodes are connected to the positive connection terminal 12 and the negative connection terminal 13, respectively. The connector may be configured as a contact type or a jack type connector so that the power cord of the high voltage indicator light can be connected thereto and thereby connected to the positive and negative connection terminals 12, 13. The connector may also be configured as a socket type connector, such as a bayonet type or a screw type socket, so that the high voltage indicator light can be directly mounted thereon.

[0022] Here, it should be noted that the high-voltage indicator light can be placed in any position that is easily visible to the operator, and is detachably connected to the connector of the high-voltage indicator 21 through its power cord. Of course, the high-voltage indicator light can also be directly installed on the high-voltage distribution box, especially detachably installed on the connector. In addition, the high-voltage indicator light can be configured to be in a constant light state when the high voltage between the positive connection terminal 12 and the negative connection terminal 13 is higher than a set value.

[0023] It can be understood that the above-mentioned set voltage value is a human safety voltage value that can be determined based on one or more conditions such as the workplace, operator conditions, usage mode, power supply mode, and line conditions. For example, in a particularly dangerous environment, the indicator light can be limited to remain on at a voltage value higher than 42V. In an environment with a risk of electric shock, the set voltage value is 36V or 24V. When the humidity of the environment is high, the set voltage value can be 12V or 6V.

[0024] As an exemplary embodiment of the first detection device, Figure 2 As shown, the detection connector 31 may include two connection terminals, namely a positive connection terminal 311 and a negative connection terminal 312. The positive connection terminal 311 and the negative connection terminal 312 may have two first mounting seats or first mounting holes 1121 respectively arranged at the first mounting position 112 (see in particular Figure 3 , in which a single elongated first mounting seat is shown in the form of a metal contact or contact piece, and the positive electrode connection terminal 12 and the negative electrode connection terminal 13 in the form of a copper busbar can be connected via a first connecting line 313 and a second connecting line 314 respectively.

[0025] In other embodiments, as can be obtained from Figure 3As can be seen, it is also conceivable to arrange the positive connection terminal 311 and the negative connection terminal 312 of the detection connector 31 into a whole through a single connection plate, and fix the connection plate in the single first mounting hole 1121 by bolts.

[0026] According to a further exemplary embodiment of the first detection device 3, Figures 2 to 4 As shown, the first detection device 3 may also include at least one first resistor 32 connected in series in the first connection line 313 and at least one second resistor 33 connected in series in the second connection line 314. In this way, when the operator's hand accidentally touches the positive connection terminal 311 connected to the positive connection terminal 12 or the negative connection terminal 312 connected to the negative connection terminal 13 and thereby a current loop passing through the human body may be formed between the positive connection terminal 12 or the negative connection terminal 13 and the earth, the first resistor 32 or the second resistor 33 can reduce or limit the current flowing through the human body to a safe current.

[0027] According to the maximum voltage value of the high-voltage distribution box and the power usage environment of the high-voltage distribution box, the total resistance value of the at least one first resistor 32 can be between 100KΩ and 150KΩ, and the total resistance value of the at least one second resistor 33 can be between 100KΩ and 150KΩ.

[0028] In a further preferred embodiment of the present disclosure, the operator protection system may further include a transparent cover plate (not shown) capable of closing the top opening of the housing 1. The transparent cover plate may be provided with at least one through hole, which may be configured to allow only a probe of an external electrical measuring instrument to pass through, and arranged to be aligned with the positive connection terminal 12 and the negative connection terminal 13 in the housing 1. In this way, the operator can also clearly see through the transparent cover plate whether the interior of the housing 1 is blackened and smoked due to current breakdown. Specifically, Figure 2 As shown, the shell 1 is provided with a plurality of screw columns 14 whose height is lower than that of the side wall 11 at intervals along its circumference, and the transparent cover plate can be provided with a plurality of screw holes corresponding to the plurality of screw columns 14, and can be fixed to the shell 1 by screws passing through the screw holes and the screw columns 14.

[0029] The transparent cover plate can be arranged below the metal cover plate 4 of the high-voltage distribution box. Here, the metal cover plate 4 can be provided with a plurality of first connection ears 42 having first connection holes 41 at intervals along its periphery, and a plurality of second connection ears 16 having second connection holes 15 can be provided at intervals at the top periphery of the housing 1 corresponding to the opening, and the metal cover plate 4 can be fixed to the housing 1 by means of screws passing through the first connection holes 41 and the second connection holes 15. Advantageously, a sealing ring 5 can also be provided between the top periphery of the housing 1 and the metal cover plate 4 to ensure the sealing of the internal space of the housing 1.

[0030] Industrial Applicability

[0031] The installation and use of the operator protection system of the present disclosure is described below.

[0032] When the second detection device 2 is installed to the shell 1, a connector that can be used to connect the high-voltage indicator light can be passed through the second mounting hole 1111 and fixed to the side wall 11 of the shell 1 by screws, and then the two ends of the first wire 22 are respectively connected to one connector of the connector and the positive connection terminal 12, and the two ends of the second wire 23 are respectively connected to the other connector of the connector and the negative connection terminal 13.

[0033] When the first detection device 3 is mounted on the housing 1, the detection connector 31 can be passed through the first mounting hole 1121 and fixed to the side wall 11 of the housing 1 by screws, so that the positive connection terminal 311 and the negative connection terminal 312 in the form of a contact or a jack face the outside of the housing 1. Then, the two ends of the first connection line 313 connected to the first resistor 32 are respectively connected to the positive connection terminal 311 and the positive connection terminal 12, and the two ends of the second connection line 314 connected to the second resistor 33 are respectively connected to the negative connection terminal 312 and the negative connection terminal 13. Thus, an operator protection system installed on the high-voltage distribution box is formed.

[0034] When the high-voltage distribution box needs to be repaired or inspected, the high-voltage distribution box in the prior art may not be powered off in time due to contactor failure after the system issues a power-off command, or the high-voltage distribution box may be reverse-charged by the instantaneous high voltage generated by the external electrical equipment connected to the high-voltage distribution box after normal power off, resulting in residual high voltage in the high-voltage distribution box, which may bring serious safety risks to maintenance personnel when repairing the high-voltage distribution box.

[0035] For the high-voltage distribution box equipped with the operator protection system of the present disclosure, when it is working normally, the voltage value of the main circuit between the positive and negative connection terminals 12 and 13 is usually higher than the voltage setting value, so that the high-voltage indicator light connected to the connector of the second detection device 2 remains on. After disconnecting the connection between the high-voltage distribution box and the power supply, if there is still residual voltage in the high-voltage distribution box, as long as the voltage value of the main circuit is greater than the set voltage value, the high-voltage indicator light remains on, reminding the operator that the high-voltage distribution box cannot be operated now. When the voltage value of the residual voltage is less than the set voltage value after waiting for a period of time, the high-voltage indicator light goes out, and the operator can safely open the high-voltage distribution box for maintenance or overhaul operations.

[0036] As a double protection measure, the operator can also insert the probes of an external electrical measuring instrument into the positive connection terminal 311 and the negative connection terminal 312 of the detection connector 31 to further determine whether the voltage value of the main circuit in the high-voltage distribution box is safe after power failure.

[0037] In addition, after opening the metal cover 4, the operator can also view the internal conditions of the high-voltage distribution box through the transparent cover, and measure the voltage value of the main circuit inside the shell 1 by inserting the probe of an external electrical measuring instrument into the through hole on the transparent cover.

[0038] Although the overall concept of the present disclosure has been described in conjunction with the embodiments, those skilled in the art will appreciate that various changes and modifications may be made to the embodiments without departing from the principles and spirit of the overall concept of the present disclosure.

Claims

1. An operator protection system for a high-voltage distribution box, the high-voltage distribution box comprising a housing (1), the housing (1) comprising at least one side wall (11), and a positive connection terminal (12) and a negative connection terminal (13) for connecting to the positive and negative electrodes of a power source, respectively, are arranged in the housing (1), characterized in that: The operator protection system comprises: A first detection device (3), the first detection device (3) comprising a detection connection piece (31) arranged at a first installation position (112) of the side wall (11), the detection connection piece (31) being electrically connected to the positive electrode connection terminal (12) and the negative electrode connection terminal (13) respectively, and being configured to be connected to an external electrical measuring instrument, The first mounting position (112) is provided with two first mounting holes (1121), and the detection connection member (31) comprises a positive connection terminal (311) and a negative connection terminal (312) respectively arranged in the two first mounting holes (1121), the positive connection terminal (311) is connected to the positive electrode connection terminal (12) via a first connection line (313), and the negative connection terminal (312) is connected to the negative electrode connection terminal (13) via a second connection line (314).

2. The operator protection system according to claim 1, characterized in that: The operator protection system further comprises a second detection device (2), the second detection device (2) comprising a high voltage indicator (21) arranged at a second mounting position (111) of the side wall (11), the high voltage indicator (21) being electrically connected to the positive connection terminal (12) and the negative connection terminal (13) through a first wire (22) and a second wire (23), respectively, and being configured to emit a visible signal when the voltage between the positive connection terminal (12) and the negative connection terminal (13) is higher than a set voltage value.

3. The operator protection system according to claim 1 or 2, characterized in that: The operator protection system further comprises a transparent cover plate for closing the housing (1), wherein the transparent cover plate is provided with at least one through hole for only the probe of the external electrical measuring instrument to pass through.

4. The operator protection system according to claim 1, characterized in that: The first detection device (3) further comprises at least one first resistor (32) connected in series in the first connecting line (313) and at least one second resistor (33) connected in series in the second connecting line (314).

5. The operator protection system according to claim 4, characterized in that: The total resistance value of the at least one first resistor (32) is between 100KΩ and 150KΩ, and the total resistance value of the at least one second resistor (33) is between 100KΩ and 150KΩ.

6. The operator protection system according to claim 2, characterized in that: The high voltage indicator (21) comprises a connector that can be used to connect a high voltage indicator light, and the high voltage indicator light is configured to be in a constant light state when the voltage between the positive electrode connection terminal (12) and the negative electrode connection terminal (13) is higher than a set voltage value.

7. The operator protection system according to claim 6, characterized in that: The set voltage value is a human safety voltage value determined based on one or more conditions including the working place, operator conditions, usage mode, power supply mode, and line conditions.

8. The operator protection system according to claim 6, characterized in that: The second mounting position (111) is provided with a second mounting hole (1111), and the connector is arranged in the second mounting hole (1111).

9. An engineering machine, characterized in that: The construction machine comprises a high voltage distribution box and an operator protection system according to any one of claims 1 to 8.

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