Magnetic starter

Abstract

The invention relates to a magnetic starter which comprises an explosion-proof shell and a module body, the explosion-proof shell comprises a front door and a shell body, an explosion-proof quick plug is arranged on the side face of the shell body, and a quick socket used for being electrically connected with a power line entering the shell body through the explosion-proof quick plug is arranged in the shell body. A quick socket is arranged in the module body, a wiring terminal group matched with the quick socket is arranged on one surface, corresponding to the quick socket, of the module body, the module body is movably arranged in a shell, the module body is in plug-in connection with the quick socket, and a locking device used for limiting opening and closing of a front door is arranged on one side of the shell. According to the technical scheme, the explosion-proof quick plug is arranged, an explosion-proof wiring cavity is omitted, and the size of the magnetic starter is further reduced; the module body is electrically connected with the quick socket through the wiring terminal group to form a main loop, so that quick plugging is facilitated, and disassembly and assembly are convenient; the module body is integrated, so that miniaturization is facilitated; after being miniaturized, the magnetic starter can be taken and taken at any time and is convenient to use.

Description

Technical Field

[0001] The present invention belongs to the technical field of starters, and in particular relates to a magnetic starter. Background Art

[0002] Magnetic starters are widely used in coal mines and other environments where explosive gases (methane mixtures) are present. Their primary function is to remotely control motors, enabling them to stop, reverse, and perform other operations. Underground mine production typically requires a variety of electrical equipment. To prevent contact between these equipment and flammable and explosive gases, magnetic starters with air isolation are essential. A single switch typically weighs approximately 200 kilograms, making it difficult to transport. Multiple sub-switches or long-distance wiring are required. Due to the complex underground environment, the aforementioned methods are inconvenient and unsafe for circuit applications involving low-power electrical equipment. Therefore, the miniaturization of magnetic starters is an urgent problem to be solved, but there are the following problems in miniaturizing magnetic starters: 1. Safety. Existing magnetic starters require a flameproof wiring chamber for circuit connection. How to safely achieve circuit connection after miniaturization? 2. The voltage in mines is usually switched between 1140V and 660V. The existing technology requires switching the voltage through a manual switch, or changing the control transformer winding tap to switch the voltage, which is inconvenient to use and not conducive to miniaturization. 3. The structure of the existing magnetic starter is complex. How to modularize it and facilitate maintenance in a miniaturized space. Summary of the Invention

[0003] In summary, in order to overcome the deficiencies of the prior art, the present invention provides a magnetic starter.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a magnetic starter, comprising a flameproof enclosure and a module body, the flameproof enclosure comprising a front door and a shell, a flameproof quick plug being provided on the side of the shell, a quick socket being provided in the shell for electrically connecting to a power cord entering the shell through the flameproof quick plug, a terminal group being provided on a side of the module body corresponding to the quick socket, the module body being movably provided in the shell, the module body being plugged into the quick socket, and a locking device being provided on one side of the shell for limiting the opening and closing of the front door.

[0005] By adopting the above technical solution, an explosion-proof quick plug is provided and the explosion-proof wiring cavity is eliminated, thereby further reducing the size of the magnetic starter; the module body forms a main circuit electrical connection with the quick socket through the wiring terminal group, which is convenient for quick plugging and disassembly; the module body is integrated and convenient for miniaturization; after the magnetic starter is miniaturized, it can be taken away and used conveniently.

[0006] The present invention further provides: the module body includes a module frame, the module frame is provided with a protector, an isolating switch, a contactor and a mutual inductor, the terminal group includes an inner end and an outer end, the inner end is electrically connected to the isolating switch, the contactor, the mutual inductor and the outer end in sequence, and the outer end is adapted to the quick socket.

[0007] By adopting the above technical solution, the inner end is electrically connected to the disconnector, contactor, transformer and outer end in sequence to form a main circuit. The transformer can adopt a hanging wire type ring transformer, which further facilitates miniaturization. At the same time, the protector, disconnector, contactor and transformer are all set on the module rack and quickly electrically connected to the quick socket of the flameproof enclosure through the terminal group. The module body is integrated to facilitate quick disassembly and assembly.

[0008] The present invention further provides: the module body also includes a transformer and a circuit board, the circuit board includes a control circuit for controlling the transformer to automatically switch voltage, the control circuit includes a single-chip microcomputer, the transformer is electrically connected to the relay through the control circuit, and the relay is electrically connected to the protector and the contactor respectively.

[0009] By adopting the above technical solution, the circuit board is integrated. The existing underground voltage is usually switched between 1140V and 660V. The existing technology requires switching the voltage through a manual conversion switch or changing the line, which is inconvenient to use. In this technical solution, the circuit board control circuit adds an automatic voltage switching function. The control circuit uses the sampling voltage size (15v) to determine whether the input voltage is 1140V or 660V. The output control voltage (36v, the control voltage can be changed according to demand) is calculated by the single-chip microcomputer. It automatically switches according to the input voltage to control the voltage output. It is more convenient and labor-saving to use, does not require manual participation, does not require manual line change, is convenient for integration, and is conducive to the miniaturization of the shell space; an R-type transformer is used, which is small in size and high in power, which is conducive to the miniaturization of the magnetic starter.

[0010] The present invention further provides that: the circuit board also includes an auxiliary closing circuit for auxiliary closing during undervoltage, the auxiliary closing circuit includes a capacitor energy storage board, and the capacitor energy storage board is electrically connected to the control circuit and the contactor respectively.

[0011] By adopting the above technical solution, in the mine, it is necessary to be able to close and open the switch normally under the condition of 70% undervoltage. Due to the miniaturization of the transformer and the automatic voltage switching function, when the input voltage is 1140V, the output power is full power, and when the input voltage is 660V, the output power is only half of the design power. Once an undervoltage occurs, the switch cannot be closed normally. In this technical solution, the circuit board adds an auxiliary closing circuit. When an undervoltage occurs, the contactor cannot be closed due to insufficient output power. The capacitor energy storage board compensates the output power and assists the contactor in closing. Since circuit-assisted closing is adopted instead of mechanical-assisted closing and opening, the structure is simplified, which is conducive to miniaturization. At the same time, the technical solution can be used to adopt a miniaturized transformer, which further facilitates the miniaturization of the overall magnetic starter.

[0012] The present invention further provides that: the circuit board also includes a detection circuit and a leakage detection protection circuit for protecting the protector, the detection circuit is arranged between the protector and the contactor, the leakage detection protection circuit includes an inductor, and the leakage detection protection circuit is connected in series with the detection circuit.

[0013] By adopting the above technical solution, the detection circuit in the existing technology is electrically connected to the contactor and the protector in sequence. Under normal circumstances, when the switch is closed, the auxiliary contact is disconnected and there is no current. However, since 1140V is a high voltage, the auxiliary contact may not be able to disconnect or may be delayed in disconnecting. At this time, the high voltage is directly connected to the protector, which will cause damage to the protector. In this technical solution, the leakage detection protection circuit is connected in series with the detection circuit. Since the inductor passes DC and isolates AC, even if the auxiliary contact may not be able to disconnect or may be delayed in disconnecting, the high voltage is reduced by the inductor and then connected to the protector, thereby protecting the detection circuit. At the same time, since the capacitor is integrated on the circuit board, miniaturization is convenient.

[0014] The present invention further provides that: an emergency stop button is provided on one side of the module body corresponding to the locking device, the locking device includes an emergency stop operating mechanism for operating the emergency stop button and a switching switch for controlling the isolating switch, and a locking assembly is provided between the emergency stop operating mechanism and the switching switch.

[0015] By adopting the above technical solution, the emergency stop button is electrically connected to the common end, and the emergency stop operating mechanism and the transfer switch are linked through the locking component. The emergency stop operating mechanism must first contact the emergency stop button to cause an emergency stop and power outage in the module body, ensuring that the transfer switch is operated in a power-off state in the shell, which can effectively prevent the isolating switch from being operated under load and has high safety.

[0016] The present invention is further provided with: the emergency stop operating mechanism includes a button arranged outside the shell and an operating rod arranged inside the shell, a clamping portion is provided at the front end of the operating rod, the conversion switch includes a rotating handle arranged outside the shell and a linkage rod arranged inside the shell for driving the isolating switch to rotate, the locking assembly includes a rotating clamp connected to the linkage rod, and a plurality of clamping slots adapted to the clamping portion are provided at the lower end of the rotating clamp. When the button drives the operating rod to move forward and abut against the emergency stop button, the clamping portion disengages from the clamping slot to release the positioning state of the linkage rod.

[0017] By adopting the above technical solution, the existing locking assembly adopts a locking link outside the shell, which is large in size. The present technical solution adopts a built-in rotating clamp, which simplifies the structure, is small in size, is convenient for internal integration, and is conducive to miniaturization; the button drives the operating rod to move forward and counteract the emergency stop button, so that the power supply is in a tripped state. At this time, the clamp moves forward and counteracts the emergency stop button. The diameter of the operating rod is smaller than the diameter of the clamp, so that the rotating clamp can swing without being affected by the clamp, and the positioning state is released. At this time, the rotating handle can drive the linkage rod to rotate, thereby driving the isolating switch to rotate for forward and reverse switching. The operation is simple, convenient and safe.

[0018] The present invention is further provided with: a locking assembly is provided between the rotating handle and the front door, a groove is provided at one end of the rotating handle corresponding to the front door, the locking assembly includes a mounting piece and a movable rod, the mounting piece is connected to the shell, the mounting piece is provided with a mounting hole adapted to the movable rod, the movable rod passes through the mounting piece and moves back and forth along the mounting hole, the movable rod is provided with a connecting portion detachably connected to the front door at one end corresponding to the front door, and a positioning portion is provided at the other end, when the rotating handle is rotated to the position where the isolating switch stops working, the positioning portion is aligned with the groove, the movable rod moves toward the groove to disconnect it from the front door, and when the rotating handle is in other positions, the movable rod is connected to the front door, and the positioning portion is against the rotating handle.

[0019] By adopting the above technical solution, when the movable rod is in the connected state with the front door, whether the rotating handle is movable or not is only related to the locking assembly. When the locking assembly releases the positioning state of the linkage rod, the rotating handle needs to be rotated to the position where the isolating switch stops working, so that the positioning part is aligned with the groove, and then the movable rod is operated to move forward to make it disconnected from the front door (because the mounting part limits the moving path of the movable rod, the connection part and the front door can be connected by threaded connection or clamping, etc., and it is only necessary to limit the state of the front door, and it is not limited to the connection method mentioned above). That is, the premise for opening the front door is that the isolating switch is in the stopped state. At the same time, after the front door is closed, the movable rod is in the connected state with the front door. When the positioning part exits the groove, the rotating handle can be rotated to operate the isolating switch, that is, the front door is in the closed state and the conversion switch can be operated. It has three safety protections to fully ensure that the module body located in the explosion-proof enclosure can only open the front door when it is in the tripped state, avoiding the risk of electrical failure igniting mine methane, coal dust and other explosions, and providing safety protection for maintenance personnel.

[0020] The specific implementation of the present invention will be described below with reference to the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A perspective view of an embodiment of the present invention;

[0022] Figure 2 This is a diagram of the internal structure of the rear view angle of an embodiment of the present invention;

[0023] Figure 3 A three-dimensional diagram of a module body according to an embodiment of the present invention;

[0024] Figure 4 This is a diagram showing the internal structure of a flameproof enclosure according to an embodiment of the present invention;

[0025] Figure 5 This is a diagram showing the internal structure of a module body according to an embodiment of the present invention;

[0026] Figure 6 A circuit diagram of an embodiment of the present invention;

[0027] Figure numerals: 1. Flameproof enclosure, 11. Front door, 12. Shell, 2. Module body, 21. Module rack, 22. Protector, 23. Isolating switch, 24. Contactor, 26. Transformer, 27. Circuit board, 28. Emergency stop button, 3. Flameproof quick plug, 4. Quick socket, 5. Terminal block, 51. Inner end, 52. Outer end, 6. Locking device, 61. Emergency stop operating mechanism, 611. Button, 612. Operating lever, 6121. Card portion, 62. Transfer switch, 621. Rotating handle, 6211. Groove, 622. Linkage rod, 63. Locking assembly, 631. Rotating card, 6311. Card slot, 7. Locking assembly, 71. Mounting member, 711. Mounting hole, 72. Movable rod, 721. Connecting portion, 722. Positioning portion. DETAILED DESCRIPTION

[0028] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

[0029] See attached Figure 1-6 A magnetic starter disclosed in this embodiment includes a flameproof enclosure 1 and a module body 2. The flameproof enclosure 1 includes a front door 11 and a shell 12. A flameproof quick plug 3 is provided on the side of the shell 12. A quick socket 4 is provided in the shell 12 for electrically connecting to a power cord entering the shell 12 through the flameproof quick plug 3. A terminal group 5 compatible with the quick socket 4 is provided on a side of the module body 2 corresponding to the quick socket 4. The module body 2 is movably arranged in the shell 12, and the module body 2 is plugged into the quick socket 4. A locking device 6 for limiting the opening and closing of the front door 11 is provided on one side of the shell 12.

[0030] This embodiment further provides: the module body 2 includes a module frame 21, on which a protector 22, an isolating switch 23, a contactor 24 and a mutual inductor are provided; the terminal block 5 includes an inner end 51 and an outer end 52, the inner end 51 being electrically connected to the isolating switch 23, the contactor 24, the mutual inductor and the outer end 52 in sequence, and the outer end 52 being adapted to the quick socket 4.

[0031] Since a toroidal transformer is suspended on the electric wires in this embodiment, the transformer is not shown in the drawings. However, the transformer is not limited to a toroidal transformer and may also be installed on the module rack 21.

[0032] This embodiment further configures: the module body 2 also includes a transformer 26 and a circuit board 27, the circuit board 27 includes a control circuit for controlling the transformer 26 to automatically switch voltage, the control circuit includes a single-chip microcomputer, the transformer 26 is electrically connected to the relay through the control circuit, and the relay is electrically connected to the protector 22 and the contactor 24 respectively.

[0033] This embodiment further provides that: the circuit board 27 also includes an auxiliary closing circuit for assisting closing during undervoltage, and the auxiliary closing circuit includes a capacitor energy storage board, and the capacitor energy storage board is electrically connected to the control circuit and the contactor 24 respectively.

[0034] This embodiment further provides that: the circuit board 27 also includes a detection circuit and a leakage detection protection circuit for protecting the protector 22, the detection circuit is arranged between the protector 22 and the contactor 24, the leakage detection protection circuit includes an inductor, and the leakage detection protection circuit is connected in series with the detection circuit.

[0035] This embodiment is further configured as follows: an emergency stop button 28 is provided on one side of the module body 2 corresponding to the locking device 6; the locking device 6 includes an emergency stop operating mechanism 61 for operating the emergency stop button 28 and a transfer switch 62 for controlling the isolating switch 23; a locking assembly 63 is provided between the emergency stop operating mechanism 61 and the transfer switch.

[0036] This embodiment is further configured as follows: the emergency stop operating mechanism 61 includes a button 611 arranged outside the shell 12 and an operating rod 612 arranged inside the shell 12, a clamping portion 6121 is provided at the front end of the operating rod 612, the conversion switch 62 includes a rotating handle 621 arranged outside the shell 12 and a linkage rod 622 arranged inside the shell 12 to drive the isolation switch 23 to rotate, the locking assembly 63 includes a rotating clamping member 631 connected to the linkage rod 622, and a plurality of clamping slots 6311 adapted to the clamping portion 6121 are provided at the lower end of the rotating clamping member 631. When the button 611 drives the operating rod 612 to move forward and abut against the emergency stop button 28, the clamping portion 6121 disengages from the clamping slot 6311 to release the positioning state of the linkage rod 622.

[0037] This embodiment is further configured as follows: a locking assembly 7 is provided between the rotating handle 621 and the front door 11, and a groove 6211 is provided at one end of the rotating handle 621 corresponding to the front door 11, and the locking assembly 7 includes a mounting member 71 and a movable rod 72, the mounting member 71 is connected to the shell 12, the mounting member 71 is provided with a mounting hole 711 adapted to the movable rod 72, the movable rod 72 passes through the mounting member 71 and moves back and forth along the mounting hole 711, and the movable rod 72 is provided with a connecting portion 721 detachably connected to the front door 11 at one end corresponding to the front door 11, and a positioning portion 722 is provided at the other end. When the rotating handle 621 is rotated to the position where the isolating switch stops working, the positioning portion 722 is aligned with the groove 6211, and the movable rod 72 moves toward the groove 6211 to disconnect it from the front door 11. When the rotating handle 621 is in other positions, the movable rod 72 is connected to the front door 11, and the positioning portion 722 is against the rotating handle 621.

[0038] It should be noted that the terms "front," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. The term "between" mentioned above does not refer solely to orientations or positions but also encompasses the interactions between different components.

[0039] Although the present invention frequently uses terms such as the flameproof enclosure 1, front door 11, housing 12, module body 2, module frame 21, protector 22, disconnector 23, contactor 24, mutual inductor, transformer 26, circuit board 27, emergency stop button 28, flameproof quick plug 3, quick socket 4, terminal block 5, inner end 51, outer end 52, locking device 6, emergency stop operating mechanism 61, button 611, operating rod 612, latching portion 6121, transfer switch 62, rotating handle 621, linkage rod 622, locking assembly 63, rotating latch 631, latching slot 6311, locking assembly 7, mounting member 71, mounting hole 711, movable rod 72, connecting portion 721, and positioning portion 722, the use of other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitations is contrary to the spirit of the present invention.

Claims

1. A magnetic starter, characterized in that: It comprises a flameproof housing and a module body, wherein the flameproof housing comprises a front door and a shell, a flameproof quick plug is arranged on the side of the shell, a quick socket is arranged in the shell for electrically connecting with a power line entering the shell through the flameproof quick plug, a terminal group adapted to the quick socket is arranged on a side of the module body corresponding to the quick socket, the module body is movably arranged in the shell, the module body is plugged into the quick socket, and a locking device for limiting the opening and closing of the front door is arranged on one side of the shell.

2. A magnetic starter according to claim 1, characterized in that: The module body comprises a module frame, on which a protector, an isolating switch, a contactor and a mutual inductor are arranged, the terminal group comprises an inner end and an outer end, the inner end is electrically connected to the isolating switch, the contactor, the mutual inductor and the outer end in sequence, and the outer end is adapted to a quick socket.

3. A magnetic starter according to claim 1, characterized in that: The module body also includes a transformer and a circuit board. The circuit board includes a control circuit for controlling the transformer to automatically switch voltage. The control circuit includes a single-chip microcomputer. The transformer is electrically connected to a relay through the control circuit. The relay is electrically connected to a protector and a contactor respectively.

4. A magnetic starter according to claim 3, characterized in that: The circuit board also includes an auxiliary closing circuit for auxiliary closing during undervoltage, and the auxiliary closing circuit includes a capacitor energy storage board, and the capacitor energy storage board is electrically connected to the control circuit and the contactor respectively.

5. A magnetic starter according to claim 3, characterized in that: The circuit board also includes a detection circuit and a leakage detection protection circuit for protecting the protector. The detection circuit is arranged between the protector and the contactor. The leakage detection protection circuit includes an inductor. The leakage detection protection circuit is connected in series with the detection circuit.

6. A magnetic starter according to claim 1, characterized in that: An emergency stop button is arranged on one side of the module body corresponding to the locking device. The locking device comprises an emergency stop operating mechanism for operating the emergency stop button and a conversion switch for controlling the isolating switch. A locking assembly is arranged between the emergency stop operating mechanism and the conversion switch.

7. A magnetic starter according to claim 6, characterized in that: The emergency stop operating mechanism includes a button arranged outside the shell and an operating rod arranged inside the shell, a clamping portion is arranged at the front end of the operating rod, the conversion switch includes a rotating handle arranged outside the shell and a linkage rod arranged inside the shell for driving the isolating switch to rotate, the locking assembly includes a rotating clamp connected to the linkage rod, a plurality of clamping grooves adapted to the clamping portion are arranged at the lower end of the rotating clamp, and when the button drives the operating rod to move forward and abut against the emergency stop button, the clamping portion disengages from the clamping groove to release the positioning state of the linkage rod.

8. A magnetic starter according to claim 7, characterized in that: A locking assembly is arranged between the rotating handle and the front door, a groove is arranged at one end of the rotating handle corresponding to the front door, the locking assembly includes a mounting piece and a movable rod, the mounting piece is connected to the shell, the mounting piece is provided with a mounting hole adapted to the movable rod, the movable rod passes through the mounting piece and moves forward and backward along the mounting hole, a connecting portion detachably connected to the front door is arranged at one end of the movable rod corresponding to the front door, and a positioning portion is arranged at the other end, when the rotating handle is rotated to the position where the isolating switch stops working, the positioning portion is aligned with the groove, the movable rod moves toward the groove to disconnect it from the front door, when the rotating handle is in other positions, the movable rod is connected to the front door, and the positioning portion is against the rotating handle.

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