PLC comprehensive practical training platform
By integrating multiple module simulation operations on the PLC comprehensive training platform, the problem of single functions of the existing platform is solved, a more comprehensive industrial control technology education experience is achieved, and a diverse needs of modern industrial control technology education is met.
Patent Information
- Application Number
- CN202420842471.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-19
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2034-04-19
AI Technical Summary
The existing PLC comprehensive training platform has relatively single functions and cannot meet the diversified needs of modern industrial control technology education.
Designed a type including anti-static desktop, load-bearing skeleton, pneumatic module, stepper motor module, PLC module, elevator module, power module, indicator light module, touch module, traffic light module and frequency conversion module are The comprehensive training platform of modules provides a more comprehensive training experience through these modules.
It realizes simulated operations of pneumatic handling, stepper motor control, elevator operation, traffic signal control and frequency conversion control, meets the needs of modern industrial control technology education, and makes the learning process more intuitive and easy to operate.
Smart Images

Figure CN222190102U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a training platform, in particular to a PLC comprehensive training platform, and belongs to the technical field of industrial control teaching. Background Art
[0002] The PLC comprehensive training platform is a teaching device designed for education and training in the field of industrial automation control. It simulates the actual industrial environment, allowing students to learn the working principle, programming, debugging and maintenance skills of PLC in a close-to-real situation; the PLC comprehensive training platform can not only improve students' professional skills, but also help schools connect with enterprises and improve students' employment rate. Through this training platform, students can get training that is seamlessly connected to actual work, laying a solid foundation for their future work in the design, debugging and maintenance of automation equipment.
[0003] China's public authorized invention: CN214624049U discloses a PLC training platform, including a test bench, a PLC module installed on the test bench, a touch screen, a leakage circuit breaker switch, a power module, a relay, a contactor, a forward and reverse motor, and line ports corresponding to the PLC module, the touch screen and the forward and reverse motor, respectively. The test bench is provided with a programming module electrically connected to the PLC module and the touch screen, and the test bench is provided with a button and a traffic light demonstration module that can be used for answering programming. During learning, students write relevant programs by themselves according to the training content, import them into the PLC module or the touch screen, and realize motion control. The whole process is fully automated, efficient and fast. Students conduct single or multiple combined training through multidisciplinary knowledge such as electrical components, mechanical components, electrical principles and use, so as to continuously improve students' understanding and application of products, with rich and diverse functions to meet high-quality teaching needs.
[0004] Although this training platform can intuitively carry out basic PLC instruction exercises, simulation experiments and physical experiments of multiple PLC applications, providing good conditions for high-level design and development experiments; however, its functions are relatively single and can no longer meet the needs of modern industrial control technology education. Therefore, designing a comprehensive PLC training teaching platform has become an urgent need. Utility Model Content
[0005] In view of this, the utility model provides a PLC comprehensive training platform to solve or alleviate the technical problems existing in the prior art, and at least provide a beneficial choice.
[0006] The technical solution of the embodiment of the utility model is implemented as follows: a PLC comprehensive training platform includes an anti-static desktop, the bottom of the anti-static desktop is fixedly connected to a cabinet, one side of the upper surface of the anti-static desktop is fixedly connected to a load-bearing frame, one side of the load-bearing frame is installed with a pneumatic module, a stepper motor module, a PLC module, an elevator module, a power module, an indicator light module, a touch module, a traffic light module and a frequency conversion module, a load-breaking switch is installed on the top of one side of the cabinet, and a heavy-duty connector is installed on the bottom of one side of the cabinet;
[0007] Wherein, the pneumatic module is used to simulate pneumatic handling operations, and the pneumatic module includes a pneumatic die base, a magnetically coupled rodless cylinder, a double-bar cylinder and an air claw;
[0008] Wherein, the pneumatic die base is installed on the top of one side of the supporting frame, the magnetically coupled rodless cylinder is installed on the top of one side of the pneumatic die base, the double-bar cylinder is installed on the bottom of the output block of the magnetically coupled rodless cylinder, and the air claw is installed on the bottom of the double-bar cylinder;
[0009] Wherein, the stepper motor module is used to simulate the control operation of the stepper motor;
[0010] The PLC module is the core of the training platform, which is used to receive external signals and perform logical operations according to preset programs;
[0011] Wherein, the elevator module is used to simulate the elevator operation process;
[0012] The power supply module is used to provide a stable working power supply to the platform to ensure the normal operation of each module.
[0013] Wherein, the indicator light module is used to provide various input buttons and provide light indication;
[0014] The touch module is used to provide a human-computer interaction interface to facilitate students to operate and program;
[0015] Wherein, the traffic light module is used for traffic signal control operation;
[0016] Wherein, the frequency conversion module is used to simulate the frequency conversion control operation.
[0017] Further preferably, the stepper motor module comprises a motor die base, a stepper motor module and a motor driver;
[0018] The motor mold base is installed on the top of one side of the supporting frame, the stepper motor module is installed on the top of one side of the motor mold base, and the motor driver is installed on the bottom of one side of the motor mold base.
[0019] Further preferably, the elevator module includes an elevator module base, an adjustable display screen module, an elevator drive module and a bridge box;
[0020] The elevator mold base is installed on the top of one side of the load-bearing frame, the elevator drive module is installed on the other side of the elevator mold base, and the bridge box is installed on one side of the elevator drive module.
[0021] Further preferably, the power module includes a power module base, an emergency stop button, a circuit breaker and a power indicator light;
[0022] Among them, the power supply mold base is installed at the bottom of one side of the supporting frame, the emergency stop button is installed at the bottom of one side of the power supply mold base, the circuit breaker is installed in the middle of one side of the power supply mold base, and the power indicator light is installed at the top of one side of the power supply mold base.
[0023] Further preferably, the indicator light module includes an indicator mold base and a plurality of button indicator lights;
[0024] Wherein, the indicator mold base is installed at the bottom of one side of the bearing frame, and the plurality of button indicator lights are installed at one side of the indicator mold base;
[0025] The touch module includes a touch module base and a touch screen;
[0026] Wherein, the touch mold base is installed in the middle of one side of the supporting frame, and the touch screen is installed on one side of the touch mold base.
[0027] Further preferably, the traffic light module includes a traffic module base and a plurality of traffic lights;
[0028] Wherein, the traffic mold base is installed in the middle of one side of the bearing frame, and a plurality of traffic lights are installed in the middle of one side of the traffic mold base;
[0029] The frequency conversion module includes a frequency conversion module base, a frequency converter and a dial;
[0030] The frequency conversion mold base is installed at the bottom of one side of the supporting frame, the frequency converter is installed at one side of the frequency conversion mold base, and the dial is installed at the other side of the dial.
[0031] Further preferably, the PLC module includes a PLC module base, a PLC module and a plurality of wiring ports;
[0032] Among them, the PLC mold base is installed on the top of one side of the supporting frame, the PLC module is installed in the middle of one side of the PLC mold base, and several wiring ports are respectively installed on one side of the pneumatic mold base, motor mold base, PLC mold base, elevator mold base, power mold base, indicator mold base, touch mold base, traffic mold base and frequency conversion mold base.
[0033] Further preferably, the front surface of the cabinet is hinged with a left-opening door, a right-opening door and a single-opening door through hinges, and hidden handles are installed on one side of the inner side walls of the left-opening door, the right-opening door and the single-opening door, and four casters are symmetrically installed on the bottom of the cabinet.
[0034] Since the embodiment of the utility model adopts the above technical scheme, it has the following advantages: the utility model provides a human-computer interaction interface by utilizing a touch module to facilitate programming and control operations, and then sends a control signal to each module through the PLC module, so that each module performs a corresponding operation according to the control signal, so that the training platform can simulate pneumatic handling, stepper motor control, elevator operation, traffic signal control and simulated frequency conversion control operations, making the functions of the training platform more comprehensive and meeting the needs of modern industrial control technology education, and each module is reasonably laid out and configured on the load-bearing frame, making the learning process more intuitive and easy to operate.
[0035] The above summary is for the purpose of description only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the utility model will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0037] Figure 1 It is a structural diagram of the utility model;
[0038] Figure 2 It is an axonometric view of the utility model.
[0039] Figure numerals: 1, pneumatic module; 2, stepper motor module; 3, PLC module; 4, elevator module; 5, power module; 6, indicator light module; 7, touch module; 8, traffic light module; 9, frequency conversion module; 10, load-bearing frame; 11, anti-static desktop; 12, cabinet; 13, left-opening door; 14, right-opening door; 15, single-opening door; 16, load-breaking switch; 17, heavy-duty connector; 18, hinge; 19, concealed buckle; 20, caster; 101, pneumatic mold base; 102, magnetically coupled rodless cylinder; 103, double-bar cylinder; 104, air claw; 201, motor mold base ; 202, stepper motor module; 203, motor driver; 301, PLC mold base; 302, PLC module; 303, wiring port; 401, elevator mold base; 402, adjustable display module; 403, elevator drive module; 404, bridge box; 501, power mold base; 502, emergency stop button; 503, circuit breaker; 504, power indicator light; 601, indication mold base; 602, button indicator light; 701, touch mold base; 702, touch screen; 801, traffic mold base; 802, traffic light; 901, frequency conversion mold base; 902, frequency converter; 903, dial. DETAILED DESCRIPTION
[0040] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.
[0041] It should be noted that the terms "first", "second", "symmetrical", "array", etc. are only used to distinguish between description and position description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the definition of "first", "symmetrical", etc. can explicitly or implicitly include one or more of these features; similarly, when the number of certain features is not limited in the form of words such as "two" or "three", it should be noted that this feature also explicitly or implicitly includes one or more feature quantities.
[0042] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.
[0043] like Figure 1-2As shown, the embodiment of the utility model provides a PLC comprehensive training platform, including an anti-static desktop 11, the bottom of the anti-static desktop 11 is fixedly connected to a cabinet 12, one side of the upper surface of the anti-static desktop 11 is fixedly connected to a load-bearing frame 10, one side of the load-bearing frame 10 is installed with a pneumatic module 1, a stepper motor module 2, a PLC module 3, an elevator module 4, a power module 5, an indicator light module 6, a touch module 7, a traffic light module 8 and a frequency conversion module 9, a load-breaking switch 16 is installed on the top of one side of the cabinet 12, and a heavy-duty connector 17 is installed on the bottom of one side of the cabinet 12;
[0044] The pneumatic module 1 is used to simulate pneumatic handling operations, and the pneumatic module 1 includes a pneumatic die base 101, a magnetically coupled rodless cylinder 102, a double-bar cylinder 103 and an air claw 104;
[0045] Among them, the pneumatic mold base 101 is installed on the top of one side of the supporting frame 10, the magnetically coupled rodless cylinder 102 is installed on the top of one side of the pneumatic mold base 101, the double-bar cylinder 103 is installed on the bottom of the output block of the magnetically coupled rodless cylinder 102, and the air claw 104 is installed on the bottom of the double-bar cylinder 103;
[0046] Wherein, the stepper motor module 2 is used to simulate the control operation of the stepper motor;
[0047] Among them, PLC module 3 is the core of the training platform, which is used to receive external signals and perform logical operations according to preset programs;
[0048] Among them, the elevator module 4 is used to simulate the elevator operation process;
[0049] Among them, the power module 5 is used to provide a stable working power supply for the platform to ensure the normal operation of each module;
[0050] Among them, the indicator light module 6 is used to provide various input buttons and provide light indication;
[0051] Among them, the touch module 7 is used to provide a human-computer interaction interface to facilitate students to operate and program;
[0052] Among them, the traffic light module 8 is used for traffic signal control operation;
[0053] The frequency conversion module 9 is used to simulate the frequency conversion control operation.
[0054] In one embodiment, the stepper motor module 2 includes a motor mold base 201, a stepper motor module 202 and a motor driver 203;
[0055] The motor mold base 201 is installed on the top of one side of the supporting frame 10, the stepper motor module 202 is installed on the top of one side of the motor mold base 201, and the motor driver 203 is installed on the bottom of one side of the motor mold base 201;
[0056] The stepper motor module 202 is controlled by the motor driver 203 to rotate according to a specific number of steps, thereby achieving precise position control, so that learners can learn the control principle and application of stepper motors through this module.
[0057] In one embodiment, the elevator module 4 includes an elevator module base 401, an adjustable display screen module 402, an elevator drive module 403 and a bridge box 404;
[0058] The elevator mold base 401 is installed on the top of one side of the load-bearing frame 10, the elevator drive module 403 is installed on the other side of the elevator mold base 401, and the bridge box 404 is installed on one side of the elevator drive module 403;
[0059] By simulating the operation process of a real elevator, including lifting and floor selection, learners can learn the principles and techniques of elevator control through this module.
[0060] In one embodiment, the power module 5 includes a power module base 501, an emergency stop button 502, a circuit breaker 503 and a power indicator light 504;
[0061] The power module 501 is installed at the bottom of one side of the load-bearing frame 10, the emergency stop button 502 is installed at the bottom of one side of the power module 501, the circuit breaker 503 is installed at the middle of one side of the power module 501, and the power indicator light 504 is installed at the top of one side of the power module 501; the power module 5 provides a stable working power supply for the entire platform to ensure the normal operation of each module. The power module 5 has an overload protection function to prevent excessive current from damaging the equipment.
[0062] In one embodiment, the indicator light module 6 includes an indicator mold base 601 and a plurality of button indicator lights 602;
[0063] The indicator mold base 601 is installed at the bottom of one side of the supporting frame 10, and a plurality of button indicator lights 602 are installed at one side of the indicator mold base 601;
[0064] The indicator module 6 provides various input buttons for learners to practice programming and improve programming skills
[0065] The touch module 7 includes a touch module base 701 and a touch screen 702;
[0066] The touch mold base 701 is installed in the middle of one side of the supporting frame 10, and the touch screen 702 is installed on one side of the touch mold base 701;
[0067] The touch screen 702 provides a human-computer interaction interface for the trainees, so that the trainees can directly operate and program on the touch screen 702 .
[0068] In one embodiment, the traffic light module 8 includes a traffic module base 801 and a plurality of traffic lights 802;
[0069] The traffic mold base 801 is installed in the middle of one side of the load-bearing frame 10, and a plurality of traffic lights 802 are installed in the middle of one side of the traffic mold base 801;
[0070] Through the simulation of traffic signal control, learners can understand and master the principles and techniques of traffic signal control through this module.
[0071] The frequency conversion module 9 includes a frequency conversion module base 901, a frequency converter 902 and a dial 903;
[0072] Among them, the frequency conversion mold base 901 is installed at the bottom of one side of the supporting frame 10, the frequency converter 902 is installed on one side of the frequency conversion mold base 901, and the dial 903 is installed on the other side of the dial 903; the frequency converter 902 is used for motor speed control, so that learners can understand the working principle and control technology of the frequency converter 902 through this module.
[0073] In one embodiment, the PLC module 3 includes a PLC module base 301, a PLC module 302 and a plurality of connection ports 303;
[0074] Among them, the PLC mold base 301 is installed on the top of one side of the supporting frame 10, the PLC module 302 is installed in the middle of one side of the PLC mold base 301, and a number of wiring ports 303 are respectively installed on one side of the pneumatic mold base 101, the motor mold base 201, the PLC mold base 301, the elevator mold base 401, the power mold base 501, the indicator mold base 601, the touch mold base 701, the traffic mold base 801 and the frequency conversion mold base 901; the modules are connected by quick-connect wires through the wiring ports 303, and the entered program is logically operated according to the preset program through the PLC module 302.
[0075] In one embodiment, the front surface of the cabinet 12 is hinged with a left door 13, a right door 14 and a single door 15 through hinges 18, and the inner side walls of the left door 13, the right door 14 and the single door 15 are all installed with concealed handles 19, and four casters 20 are symmetrically installed at the bottom of the cabinet 12; the casters 20 make it easy to move the training platform over short distances, and the left door 13, the right door 14 and the single door 15 are used to control the opening and closing of the cabinet 12.
[0076] When the utility model is working: the heavy-duty connector 17 is used to power the entire training platform, and then a human-computer interaction interface is provided for trainees through the touch screen 702, so that trainees can directly operate and program on the touch screen 702, and can view the control logic of the PLC module 302 and the working status of each module in real time through the touch screen 702, and then use quick-connect patch cords through the wiring port 303 to connect the modules according to teaching needs.
[0077] When pneumatic handling simulation operation is required, the teaching program is entered into the PLC module 302, and the PLC module 302 performs logical operations according to the preset program, and the magnetically coupled rodless cylinder 102, the double-bar cylinder 103 and the air claw 104 are controlled by the relay according to the operation result. The working magnetically coupled rodless cylinder 102 drives the double-bar cylinder 103 and the air claw 104 to move horizontally, the working double-bar cylinder 103 drives the air claw 104 to move up and down, and the working air claw 104 performs a grasping operation to complete the pneumatic handling simulation.
[0078] When a stepper motor control simulation operation is required, the corresponding program is entered into the PLC module 302, and the PLC module 302 performs logical operations according to the preset program, and generates control instructions according to the operation results, and then the motor driver 203 drives the stepper motor module 202 to perform simulation operations according to the control instructions.
[0079] When it is necessary to simulate the operation of the elevator, the corresponding program is entered into the PLC module 302, and the PLC module 302 performs logical operations according to the preset program, and then generates control feedback by pressing the button on the indicator mold base 601. Then, the PLC module 302 uses the relay to control the elevator drive module 403 according to the control feedback, so that the elevator drive module 403 can drive the bridge box 404 to move up and down to simulate the elevator operation.
[0080] When it is necessary to perform traffic signal control and simulated frequency conversion control simulation operations, the above operations can be repeated as needed to complete the corresponding simulation control, so that the training platform can simulate pneumatic handling, stepper motor control, elevator operation, traffic signal control and simulated frequency conversion control operations, making the training platform more comprehensive and meeting the needs of modern industrial control technology education. In addition, each module is reasonably arranged and configured on the load-bearing frame 10, making the learning process more intuitive and easy to operate.
[0081] The load circuit breaker 16 is used to protect the circuit and load of the training platform. When the circuit fails or exceeds the load capacity, the circuit can be cut off in time to prevent the spread of the fault. At the same time, the load in the circuit can be controlled to achieve the switch, adjustment and control of the load. The left door 13, the right door 14 and the single door 15 are used to control the opening and closing of the cabinet 12. The cabinet 12 and the load-bearing frame 10 are made of aluminum alloy and sheet metal structure, which ensures the strength and stability of the training platform and has excellent heat dissipation performance.
[0082] The above are only specific implementations of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A PLC comprehensive training platform, comprising an anti-static desktop (11), characterized in that: The bottom of the antistatic desktop (11) is fixedly connected to a cabinet (12); one side of the upper surface of the antistatic desktop (11) is fixedly connected to a load-bearing frame (10); one side of the load-bearing frame (10) is installed with a pneumatic module (1), a stepper motor module (2), a PLC module (3), an elevator module (4), a power module (5), an indicator light module (6), a touch module (7), a traffic light module (8) and a frequency conversion module (9); a load-breaking switch (16) is installed on the top of one side of the cabinet (12); and a heavy-duty connector (17) is installed on the bottom of one side of the cabinet (12); The pneumatic module (1) is used to simulate pneumatic handling operations, and the pneumatic module (1) comprises a pneumatic die base (101), a magnetically coupled rodless cylinder (102), a double-bar cylinder (103) and an air claw (104); The pneumatic mold base (101) is installed on the top of one side of the supporting frame (10), the magnetically coupled rodless cylinder (102) is installed on the top of one side of the pneumatic mold base (101), the double-bar cylinder (103) is installed on the bottom of the output block of the magnetically coupled rodless cylinder (102), and the air claw (104) is installed on the bottom of the double-bar cylinder (103); Wherein, the stepper motor module (2) is used to simulate the control operation of the stepper motor; The PLC module (3) is the core of the training platform and is used to receive external signals and perform logic operations according to a preset program; Wherein, the elevator module (4) is used to simulate the elevator operation process; The power supply module (5) is used to provide a stable working power supply to the platform to ensure the normal operation of each module; Wherein, the indicator light module (6) is used to provide various input buttons and provide light indication; The touch module (7) is used to provide a human-computer interaction interface to facilitate the trainees to operate and program; Wherein, the traffic light module (8) is used for traffic signal control operation; Wherein, the frequency conversion module (9) is used to simulate frequency conversion control operation.
2. The PLC comprehensive training platform according to claim 1 is characterized in that: The stepper motor module (2) comprises a motor mold base (201), a stepper motor module (202) and a motor driver (203); The motor mold base (201) is installed on the top of one side of the supporting frame (10), the stepper motor module (202) is installed on the top of one side of the motor mold base (201), and the motor driver (203) is installed on the bottom of one side of the motor mold base (201).
3. The PLC comprehensive training platform according to claim 2 is characterized in that: The elevator module (4) comprises an elevator module base (401), an adjustable display screen module (402), an elevator drive module (403) and a bridge box (404); The elevator mold base (401) is installed on the top of one side of the supporting frame (10), the elevator drive module (403) is installed on the other side of the elevator mold base (401), and the bridge box (404) is installed on one side of the elevator drive module (403).
4. The PLC comprehensive training platform according to claim 3 is characterized in that: The power module (5) comprises a power module base (501), an emergency stop button (502), a circuit breaker (503) and a power indicator light (504); The power mold base (501) is installed at the bottom of one side of the supporting frame (10), the emergency stop button (502) is installed at the bottom of one side of the power mold base (501), the circuit breaker (503) is installed at the middle of one side of the power mold base (501), and the power indicator light (504) is installed at the top of one side of the power mold base (501).
5. The PLC comprehensive training platform according to claim 4 is characterized in that: The indicator light module (6) comprises an indicator mold base (601) and a plurality of button indicator lights (602); The indicating mold base (601) is installed at the bottom of one side of the supporting frame (10), and the plurality of button indicator lights (602) are installed at one side of the indicating mold base (601); The touch module (7) comprises a touch module base (701) and a touch screen (702); The touch mold base (701) is installed at the middle of one side of the supporting frame (10), and the touch screen (702) is installed at one side of the touch mold base (701).
6. The PLC comprehensive training platform according to claim 5 is characterized in that: The traffic light module (8) comprises a traffic module base (801) and a plurality of traffic lights (802); The traffic mold base (801) is installed in the middle of one side of the supporting frame (10), and the plurality of traffic lights (802) are installed in the middle of one side of the traffic mold base (801); The frequency conversion module (9) comprises a frequency conversion module base (901), a frequency converter (902) and a dial (903); The frequency conversion mold base (901) is installed at the bottom of one side of the supporting frame (10), the frequency converter (902) is installed at one side of the frequency conversion mold base (901), and the dial (903) is installed at the other side of the dial (903).
7. The PLC comprehensive training platform according to claim 6 is characterized in that: The PLC module (3) comprises a PLC module base (301), a PLC module (302) and a plurality of connection ports (303); The PLC mold base (301) is installed on the top of one side of the supporting frame (10), the PLC module (302) is installed in the middle of one side of the PLC mold base (301), and the plurality of wiring ports (303) are respectively installed on one side of the pneumatic mold base (101), the motor mold base (201), the PLC mold base (301), the elevator mold base (401), the power mold base (501), the indicator mold base (601), the touch mold base (701), the traffic mold base (801) and the frequency conversion mold base (901).
8. The PLC comprehensive training platform according to claim 1 is characterized in that: The front surface of the cabinet (12) is hinged with a left-opening door (13), a right-opening door (14) and a single-opening door (15) via hinges (18); a concealed handle (19) is installed on one side of the inner side wall of the left-opening door (13), the right-opening door (14) and the single-opening door (15); and four casters (20) are symmetrically installed at the bottom of the cabinet (12).
