Intrinsic safety operation box power supply protection circuit for full face tunnel boring machine

Abstract

The utility model belongs to the technical field of intrinsic safety operation table power supply protection circuits, and discloses an intrinsic safety operation box power supply protection circuit for a full face tunnel boring machine. A 3V power supply protection circuit; the input end VIN and the ground end GND of the low-dropout linear regulator are connected with one end of the 5V power supply protection circuit, and the output ends OUT, the fourth end and the ground end GND of the low-dropout linear regulator are connected with the 3V power supply protection circuit; and the wiring terminal is connected with the other end of the 5V power supply protection circuit. For'ia 'and'ib' protection levels of coal mine products, the protection effect of elements related to intrinsic safety performance on a circuit when the elements work under normal working and fault conditions and under the condition that the maximum current, voltage and power rated values specified by element mounting conditions and temperature ranges are exceeded is effectively achieved, and the safety of the coal mine products is improved. The maximum rated value should be a normal nominal rated value for batch production specified by a component manufacturer.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of intrinsically safe operation console power protection circuits, and particularly relates to an intrinsically safe operation box power protection circuit for a full-face roadheader. Background Art

[0002] With the continuous development of current technology, in recent years, the degree of automation in coal mines in China has been increasing day by day, and mine operation safety is particularly important. To ensure continuous safe operation in a harsh mine environment with high gas and dust, the requirements for the use of mine electrical equipment are more stringent. The electrical operating system of a mine full-face roadheader requires the use of explosion-proof equipment, and the use of intrinsically safe equipment in the operation box is more frequent.

[0003] When using an intrinsically safe power supply, it must be matched with the working power supply circuit of the load, and an associated test must be carried out. It must meet the intrinsically safe test of no spark and low energy and can be used only after obtaining certification; according to the standard of the intrinsically safe power supply for coal mines, there are certain requirements for the capacitance value and inductance value contained in the circuit of the load carried by the intrinsically safe power supply, and they must be less than the value allowed by the intrinsically safe power supply; in addition, for the "ia" and "ib" protection levels, any component related to the intrinsically safe performance should not work under conditions exceeding two-thirds of the maximum current, voltage, and power ratings specified in the component installation conditions and temperature range under normal working and fault conditions. The above maximum ratings should be the normal nominal ratings specified by the component manufacturer for mass production. The present utility model proposes an intrinsically safe operation box power protection circuit for a full-face roadheader to solve the above problems. Summary of the Utility Model

[0004] Aiming at the deficiencies of the prior art, the purpose of the present disclosure is to provide an intrinsically safe operation box power protection circuit for a full-face roadheader. For the "ia" and "ib" protection levels of coal mine products, the present disclosure effectively solves the problem of the protection of the circuit when components related to the intrinsically safe performance work under conditions exceeding two-thirds of the maximum current, voltage, and power ratings specified in the component installation conditions and temperature range under normal working and fault conditions. The above maximum ratings should be the normal nominal ratings specified by the component manufacturer for mass production.

[0005] The purpose of the present disclosure can be achieved through the following technical solutions:

[0006] An intrinsically safe operation box power protection circuit for a full-face roadheader, comprising:

[0007] A 5V power protection circuit for supplying power to the operation box display screen circuit and the operation box digital output button;

[0008] A 3V power protection circuit for supplying power to the operation box CPU circuit;

[0009] Low dropout linear regulator. The input terminal VIN and the ground terminal GND of the low dropout linear regulator are connected to one end of the 5V power protection circuit. The output terminal OUT, the 4-terminal, and the ground terminal GND of the low dropout linear regulator are connected to the 3V power protection circuit. The low dropout linear regulator is used to provide a stable and reliable 3V power supply for the console circuit;

[0010] Terminal block. The terminal block is connected to the other end of the 5V power protection circuit and is used to connect the external intrinsically safe 5V power supply and the internal power supply circuit.

[0011] Further, the 5V power protection circuit includes a first line and a second line. One end of the first line is adjacent to the input terminal VIN of the low dropout linear regulator, and the other end is adjacent to the 3-terminal of the terminal block. One end of the second line is connected to the ground terminal GND of the low dropout linear regulator, and the other end is connected to the 2-terminal of the terminal block.

[0012] Further, along the direction from the terminal block to the low dropout linear regulator on the first line, a fuse F1, a Schottky diode D39, and a Schottky diode D40 are connected in series in sequence.

[0013] Further, along the direction from the terminal block to the low dropout linear regulator, a varistor R330, a capacitor C174, a heating wire R31, a zener diode D160, a zener diode D160, and a capacitor C187 are connected in parallel between the first line and the second line in sequence.

[0014] Further, one end of the varistor R330, the capacitor C174, and the heating wire R31 is connected to the first line between the fuse F1 and the Schottky diode D39, and one end of the zener diode D160, the zener diode D160, and the capacitor C187 is connected to the first line between the Schottky diode D40 and the input terminal VIN of the low dropout linear regulator.

[0015] Further, a varistor FB36 is connected in series on the second line between the heating wire R31 and the zener diode D160.

[0016] Further, a capacitor C172 is connected in parallel between the 2-terminal and the 1-terminal of the terminal block, and a capacitor C173 is connected in parallel between the 3-terminal of the terminal block and the first line between the varistor R330 and the capacitor C174.

[0017] Further, the input terminal VIN of the low dropout linear regulator is connected to the 5V power supply.

[0018] Further, the 3V power protection circuit includes a third line. One end of the third line is connected to the output terminal OUT and the 4-terminal of the low dropout linear regulator, and the other end is connected to the 3V power supply.

[0019] Further, a capacitor C183, a capacitor C186, a capacitor C184, a voltage stabilizing diode D108, and a voltage stabilizing diode D109 are connected in parallel between the ground terminal GND of the low dropout linear regulator and the third line, and the ground terminal GND of the low dropout linear regulator is connected to the ground wire.

[0020] The explanations of the nouns, conjunctions, or adjectives involved in the above technical solutions are as follows:

[0021] Fixed connection means that after the parts or components are fixed, there is no relative movement. It is divided into two types: detachable connection and non-detachable connection.

[0022] (1) Detachable connection uses screws, splines, wedge pins, etc. to fix the parts together. This connection method can be disassembled during maintenance and will not damage the parts. However, the specifications of the connecting parts used must be correct (such as the length of bolts, keys, and wedge pins), and they must be fastened properly.

[0023] (2) Non-detachable connection mainly refers to welding, riveting, and mortise fitting, etc. Since it needs to be forged, sawed, or oxy-cut to be disassembled during maintenance or replacement, the spare parts generally cannot be used twice. At the same time, during connection, attention should be paid to process quality, technical inspection, and remedial measures (such as correction, polishing, etc.).

[0024] Threaded connection means a detachable connection that connects the connected parts into one body with threaded parts (or the threaded parts of the connected parts).

[0025] Sliding connection means that two objects are in contact but not fixed, and they can slide relative to each other.

[0026] Rotational connection means that the connection between parts allows the parts to rotate relative to each other.

[0027] Advantages of the present disclosure:

[0028] For the "ia" and "ib" protection levels of coal mine products in the present disclosure, it effectively solves the protection of the circuit when components related to intrinsic safety performance work under conditions where the maximum current, voltage, and power ratings exceed two-thirds of the specified maximum current, voltage, and power ratings under the component installation conditions and temperature range during normal operation and fault conditions. The above maximum ratings should be the normal nominal ratings specified by the component manufacturer for mass production. Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0030] Figure 1It is the power protection circuit diagram of the embodiment of the present disclosure;

[0031] Figure 2 It is the 5V power protection circuit diagram of the embodiment of the present disclosure;

[0032] Figure 3 It is the 3V power protection circuit diagram of the embodiment of the present disclosure. Detailed implementation manners

[0033] Next, the technical solutions in the embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present disclosure.

[0034] In the description of the present disclosure, it should be understood that the terms "open hole", "upper", "lower", "thickness", "top", "middle", "length", "inner", "periphery", etc. indicating the orientation or positional relationship are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present disclosure.

[0035] As Figures 1-3 shown, an intrinsically safe operation box power protection circuit for a full-face roadheader includes:

[0036] The 5V power protection circuit 1 is used to supply power to the operation box display screen circuit and the operation box digital output button. Specifically, the working status and fault display of the full-face roadheader can be displayed through the display screen; the actions of the full-face roadheader can be controlled through the digital output buttons of the operation box.

[0037] The 3V power protection circuit 2 is used to supply power to the operation box CPU circuit. Specifically, the CPU circuit is used to process the programs and algorithms of the operation box.

[0038] The low-dropout linear regulator 3, the input terminal VIN and the ground terminal GND of the low-dropout linear regulator 3 are connected to one end of the 5V power protection circuit 1, and the output terminal OUT, the 4-terminal and the ground terminal GND of the low-dropout linear regulator 3 are connected to the 3V power protection circuit 2. The low-dropout linear regulator 3 is used to provide a stable and reliable 3V power supply for the operation console circuit. It precisely controls the output voltage through its internal circuit to meet the requirements under different load conditions and ensure the stable operation of electronic devices.

[0039] The terminal block 4 is connected to the other end of the 5V power protection circuit 1, and the terminal block 4 is used to connect the external intrinsically safe 5V power supply and the internal power supply circuit.

[0040] A terminal is a kind of accessory product used to achieve electrical connection and is classified as a connector in the industry. With the increasing level of industrial automation and the increasingly strict and precise requirements of industrial control, the usage of terminals is gradually increasing. With the development of the electronics industry, the application scope of terminals is becoming wider and wider, and the types are also increasing. Besides PCB board terminals, the most widely used ones also include hardware terminals, nut terminals, spring terminals, and so on.

[0041] A low dropout linear regulator is a new generation of integrated circuit voltage regulator. The biggest difference between it and the three-terminal voltage regulator is that the low dropout linear regulator (LDO) is a micro system-on-chip (SOC) with very low self-consumption. It can be used for current main channel control. The chip integrates hardware circuits such as MOSFET with extremely low on-resistance on the line, Schottky diodes, sampling resistors, and voltage-dividing resistors, and has functions such as overcurrent protection, over-temperature protection, precision reference source, differential amplifier, and delay device. PG is a new generation of LDO, with functions of self-checking the output state and delayed safe power supply, and can also be called power good, that is, "power is good or power is stable". The low dropout linear regulator usually has extremely low self-noise and a high power supply rejection ratio.

[0042] Preferably, the low dropout linear regulator 3 in this application selects the TLV117 low dropout linear regulator, and the terminal selects the terminal CON3.

[0043] As Figure 2 shown, the 5V power protection circuit 1 includes a first line and a second line. One end of the first line is adjacent to the input terminal VIN of the low dropout linear regulator 3, and the other end is adjacent to the 3-terminal of the terminal 4. One end of the second line is connected to the ground terminal GND of the low dropout linear regulator 3, and the other end is connected to the 2-terminal of the terminal 4.

[0044] On the first line, along the direction from the terminal 4 to the low dropout linear regulator 3, a fuse F1, a Schottky diode D39, and a Schottky diode D40 are connected in series in sequence.

[0045] Along the direction from the terminal 4 to the low dropout linear regulator 3, a varistor R330, a capacitor C174, a resistance wire R31, a zener diode D160, a zener diode D160, and a capacitor C187 are connected in parallel between the first line and the second line in sequence.

[0046] One end of the varistor R330, capacitor C174, and heating wire R31 is connected to the first line between the fuse F1 and the Schottky diode D39. One end of the zener diode D160, zener diode D160, and capacitor C187 is connected to the first line between the Schottky diode D40 and the input terminal VIN of the low dropout linear regulator 3.

[0047] A varistor FB36 is connected in series on the second line between the heating wire R31 and the zener diode D160.

[0048] A capacitor C172 is connected in parallel between the 2-terminal and the 1-terminal of the terminal block 4, and a capacitor C173 is connected in parallel between the 3-terminal of the terminal block 4 and the first line between the varistor R330 and the capacitor C174.

[0049] The input terminal VIN of the low dropout linear regulator 3 is connected to the power supply 5V.

[0050] As Figure 3 shown, the 3V power supply protection circuit 2 includes a third line. One end of the third line is connected to the output terminal OUT and the 4-terminal of the low dropout linear regulator 3, and the other end is connected to the power supply 3V.

[0051] A capacitor C183, capacitor C186, capacitor C184, zener diode D108, and zener diode D109 are connected in parallel between the ground terminal GND of the low dropout linear regulator 3 and the third line, and the ground terminal GND of the low dropout linear regulator 3 is connected to the ground wire.

[0052] Operating principle of the entire protection circuit: By selecting zener diodes, current-limiting resistors, and fuses that are much higher than the circuit protection parameters. When a fault occurs in the working circuit, a large current will be generated, resulting in excessive heat. Prolonged use of coal mine products under overheated conditions will affect the service life of the products. More seriously, overheating may generate sparks or combustion, which may mix with the gas in the coal mine and pose an explosion risk. Therefore, in the event of the above-mentioned faults, this protection circuit can effectively solve this problem: Select zener diodes, current-limiting resistors, and fuses that are much higher than the circuit protection parameters to cut off the circuit and play a protective role.

[0053] Functions and beneficial effects that the protection circuit can achieve: For the "i a" and "ib" protection levels of coal mine products in the present disclosure, it effectively solves the problem of protecting the circuit when components related to intrinsic safety performance operate under conditions where the maximum current, voltage, and power ratings exceed two-thirds of the specified maximum current, voltage, and power ratings within the component installation conditions and temperature range. The above maximum ratings should be the normal nominal ratings specified by the component manufacturer for mass production.

[0054] Next, verify the reliability of the 5V power supply protection circuit and the 3V power supply protection circuit:

[0055] (1) 5V Power Supply Protection Circuit:

[0056] 1) Protection Device Parameters:

[0057] Fuse F1: 250V, 50mA

[0058] Zener Diodes D160, D161: 5.1V ± 5%, 2W

[0059] 2) Protection Calculation:

[0060] Zener Diode Power:

[0061] Total Power 2W × 2 = 4W;

[0062] Power Considering One Faulty Zener Diode:

[0063] 2W * 1 = 2W

[0064] Zener Diode Power: (0.05 * 1.7)A × (5.1 * 1.05) 5.4V = 0.46W < 2W

[0065] Meets the requirements of reliable components.

[0066] (2) 3V Power Supply Protection Circuit:

[0067] 1) Protection Voltage

[0068] The protection voltage is determined by D108 (D109), and the trigger voltage is 3.6V

[0069] Table 1 Trigger Voltage and Ammeter

[0070]

[0071] 2) Zener Diodes D108, D109 Parameters: 3.6V ± 5% 5W

[0072] Fuse F1: 250V, 50mA

[0073] 3) Protection Current

[0074] The protection current is determined by fuse F1, and the nominal protection current is 0.05A

[0075] The power margin of the protection device is as follows:

[0076] According to the requirements of Ex ib protection for a single diode, the required power should be 0.05A x 3.6V x 1.5 (margin) x 1.7 (fuse melting margin) = 0.46W, and the actual power of a single zener diode is 5W, exceeding the protection requirement, for a reliable protection circuit.

[0077] In the description of this specification, the descriptions referring to the terms "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0078] The foregoing has shown and described the basic principles, main features and advantages of the present disclosure. Those skilled in the art should understand that the present disclosure is not limited by the above embodiments, and what is described in the above embodiments and the specification is only to illustrate the principles of the present disclosure. Without departing from the spirit and scope of the present disclosure, the present disclosure will have various changes and improvements, and these changes and improvements all fall within the scope of the present disclosure claimed.

Claims

1. A power protection circuit for an intrinsically safe operating box of a full-face tunnel boring machine, characterized in that: include: 5V power supply protection circuit (1), used for powering the operation box display screen circuit and the switch output button of the operation box; 3V power supply protection circuit (2), used for powering the CPU circuit of the operation box; A low voltage difference linear regulator (3), an input terminal VIN and a ground terminal GND of the low voltage difference linear regulator (3) are connected to one end of a 5V power supply protection circuit (1), an output terminal OUT, a terminal 4 and a ground terminal GND of the low voltage difference linear regulator (3) are connected to a 3V power supply protection circuit (2), and the low voltage difference linear regulator (3) is used to provide a stable and reliable 3V power supply for the operation table circuit; The wiring terminal (4) is connected to the other end of the 5V power supply protection circuit (1), and the wiring terminal (4) is used to connect the external intrinsically safe 5V power supply and the internal power supply circuit.

2. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 1 is characterized in that: The 5V power supply protection circuit (1) comprises a first circuit and a second circuit, one end of the first circuit being adjacent to an input terminal VIN of a low voltage difference linear regulator (3), and the other end being adjacent to a terminal 3 of a wiring terminal (4), and one end of the second circuit being connected to a ground terminal GND of the low voltage difference linear regulator (3), and the other end being connected to a terminal 2 of the wiring terminal (4).

3. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 2, characterized in that: A fuse F1, a Schottky diode D39 and a Schottky diode D40 are sequentially connected in series on the first line in a direction from the connection terminal (4) to the low voltage difference linear regulator (3).

4. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 3 is characterized in that: Along the direction from the connection terminal (4) to the low voltage difference linear regulator (3), a varistor R330, a capacitor C174, a resistor R31, a zener diode D160, a zener diode D160 and a capacitor C187 are sequentially connected in parallel between the first circuit and the second circuit.

5. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 4, characterized in that: The varistor R330, the capacitor C174 and one end of the resistor R31 are connected to a first circuit between the fuse F1 and the Schottky diode D39, and the voltage regulator diode D160, the voltage regulator diode D160 and one end of the capacitor C187 are connected to a first circuit between the Schottky diode D40 and the input terminal VIN of the low voltage difference linear regulator (3).

6. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 4, characterized in that: A varistor FB36 is connected in series on the second circuit between the resistor R31 and the voltage-stabilizing diode D160.

7. The intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 4, characterized in that: A capacitor C172 is connected in parallel between terminal 2 of the connection terminal (4) and terminal 1 thereof, and a capacitor C173 is connected in parallel between terminal 3 of the connection terminal (4) and the first line between the varistor R330 and the capacitor C174.

8. According to the intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 4, it is characterized in that: The input terminal VIN of the low voltage difference linear regulator (3) is connected to the power supply 5V.

9. According to the intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 1, it is characterized in that: The 3V power supply protection circuit (2) comprises a third circuit, one end of the third circuit is connected to the output end OUT and the end 4 of the low voltage difference linear regulator (3), and the other end is connected to the power supply 3V.

10. According to the intrinsically safe operating box power protection circuit for a full-face tunnel boring machine according to claim 9, it is characterized in that: A capacitor C183, a capacitor C186, a capacitor C184, a voltage regulator diode D108 and a voltage regulator diode D109 are connected in parallel between the ground terminal GND of the low voltage difference linear regulator (3) and the third line, and the ground terminal GND of the low voltage difference linear regulator (3) is connected to the ground line.

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