Heat preservation device applied to frequency conversion cabinet on gantry crane

Abstract

The utility model discloses a heat preservation device applied to a frequency conversion cabinet on a gantry crane, and relates to the field of frequency conversion cabinet heat preservation. Gantry supporting legs are symmetrically and fixedly installed at the bottom of a main beam, a control cabin is arranged on one side of the bottom of the main beam and located on one sides of the gantry supporting legs, and a walking board fixedly connected with the gantry supporting legs is arranged at the bottom of the control cabin; a hole plate is arranged at the bottom of the side, away from the control cabin, of the walking board, and the heat preservation cabin is arranged at the top of the walking board and located at the bottom of the top of the gantry; according to the heat preservation device applied to the frequency conversion cabinet on the gantry crane, the heat preservation cabin is arranged at the bottom of the top of the gantry, the gantry prevents accumulated snow from falling on the top of the heat preservation cabin, the temperature of an inner cavity of the cabin wall is increased through the heating assembly, electrical elements in the cabinet body reach the proper working temperature, and the influence of cold weather on use of the gantry crane is reduced.

Description

Technical Field

[0001] This utility model relates to frequency converter cabinet insulation technology, specifically to an insulation device applied to frequency converter cabinets on gantry cranes. Background Technology

[0002] A frequency converter cabinet is a control cabinet that uses a frequency converter to drive a power unit. It controls the motor speed by changing the power supply frequency through a built-in frequency converter, thereby achieving energy saving and efficient operation of the equipment. The frequency converter cabinet also contains components such as a PLC, a digital-to-analog converter module, and various electrical components including AC input reactors, output reactors, and DC reactors, used for circuit protection, monitoring motor operating status, and can be equipped with various control buttons and indicator lights according to system operating conditions. Due to its excellent starting performance, speed regulation performance, and significant energy-saving effect, frequency converter cabinets are widely used in many fields such as metallurgy, chemical industry, petroleum, and water supply.

[0003] The gantry crane frequency converter cabinet is an electrical control device specifically designed for gantry cranes. It integrates core components such as frequency converters and PLCs, controlling the speed of the gantry crane motor by changing the power supply frequency, thus achieving stepless speed regulation and precise control of the crane. This type of frequency converter cabinet not only improves the operational stability and positioning accuracy of the gantry crane but also significantly reduces energy consumption and noise, extending the equipment's service life. It is widely used in various fields such as construction, bridge construction, power, and shipbuilding, and is an indispensable piece of equipment in modern lifting operations.

[0004] However, the electrical components inside the frequency converter cabinet have certain temperature requirements. When the ambient temperature is too low, the performance of these components will be affected, causing them to fail to work properly. In particular, the microprocessor and other electronic components of the frequency converter may fail to start or run unstablely at low temperatures. Therefore, the frequency converter cabinet needs to be preheated before the gantry crane is used in order to ensure the normal operation of the electrical components inside the frequency converter cabinet. Utility Model Content

[0005] The purpose of this invention is to provide a heat preservation device for frequency converter cabinets on gantry cranes, so as to solve the shortcomings of the prior art where electrical components in the frequency converter cabinet cannot start or operate stably due to excessively low ambient temperature.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a heat preservation device for a frequency converter cabinet on a gantry crane, the gantry crane including a main beam, gantry legs symmetrically fixedly installed at the bottom of the main beam, an control cabin located on one side of the bottom of the main beam, the control cabin being located on one side of the gantry legs, a ladder connecting to the control cabin being provided at the bottom of the gantry legs, the ladder being fixedly connected to the gantry legs, a walkway fixedly connected to the gantry legs being provided at the bottom of the control cabin, and a perforated plate being provided at the bottom of the walkway on the side away from the control cabin, characterized in that a heat preservation device is provided on the side of the walkway away from the control cabin, the heat preservation device including a heat preservation chamber, a temperature control component, a one-way vent valve, and a heating component:

[0007] The insulated chamber is located on the top of the walkway and at the bottom of the main beam. The insulated chamber includes a chamber wall and a thermometer. The chamber wall is a cuboid structure. The top of the chamber wall is fixedly installed at the bottom of the gantry, and the bottom of the chamber wall is fixedly connected to the top of the walkway. The bottom of the chamber wall has a through hole that communicates with the perforated plate. The thermometer is located at the top of the inner cavity of the chamber wall.

[0008] The temperature control component is located at the bottom of the inner cavity of the bulkhead and at the top of the through hole opened at the bottom of the bulkhead. The temperature control component includes a support frame, a drive source, a transmission shaft, blades, a protective cylinder, a spline, slide rods, and an inner shaft. The bottom of the support frame is located at the bottom of the inner cavity of the bulkhead and above the through hole opened in the bulkhead. The drive source is fixedly installed on the top of the support frame. The transmission shaft is fixedly installed at the output end of the bottom of the drive source through a coupling. The upper ends of several slide rods are arranged in a circumferential array and fixedly installed at the bottom of the transmission shaft. The upper end of the inner shaft is rotatably installed at the middle position of the bottom of the transmission shaft and the inner shaft is located inside several slide rods. The spline is sleeved on the outer side of the lower end of the inner shaft. The lower end of the slide rod passes through the spline and is slidably connected to the spline. The spline is engaged with the inner shaft. The protective cylinder is fixedly installed at the bottom of the inner shaft. Several blades are arranged in a circumferential array on the outer side of the protective cylinder.

[0009] The one-way ventilation valve is located inside the through-hole at the bottom of the bulkhead and on the upper part of the perforated plate; the heating assembly is located on one side of the support frame.

[0010] Preferably, the insulated chamber further includes a door located on one side of the chamber wall, the door being hinged to the chamber wall, an observation window being provided on the outer side of the chamber wall, the observation window being located on the side near the walkway, and a cabinet being provided inside the chamber wall, the number of which is not less than one.

[0011] Preferably, the heating assembly includes a heat-conducting plate located on a horizontal plane between the driving source and several blades, and a resistance wire is disposed on the inner side of the heat-conducting plate.

[0012] Preferably, the one-way ventilation valve includes a mounting ring, a baffle plate, a limiting plate, a connecting rod, and a spring. The mounting ring is fixedly installed on the inner wall of a through hole in the bulkhead. The tops of several connecting rods are arranged in a circumferential array and fixedly installed on the bottom of the mounting ring. The bottoms of several connecting rods are fixedly installed on the top of the limiting plate. The spring is sleeved on the outside of the connecting rod. The connecting rod passes through the baffle plate, causing the baffle plate to slide up and down along the connecting rod. The spring is located between the baffle plate and the limiting plate.

[0013] Preferably, the temperature control assembly further includes a driven bevel gear, an outer shaft, a limiting spring, and a driving bevel gear;

[0014] An outer shaft is sleeved on the outside of the inner shaft at the lower part of the spline. The outer shaft extends through the inner cavity of the protective cylinder and is rotatably connected to the protective cylinder. The top of the outer shaft is fixedly connected to the drive shaft via a slide rod. A limiting spring is sleeved on the outside of the slide rod and is located between the spline and the drive shaft. A driving bevel gear is fixedly installed at the bottom of the outer shaft and is rotatably connected to the inner shaft. The outer shaft and the inner shaft are rotatably connected. Several driven bevel gears are distributed in a circumferential array on the circumferential side of the inner wall of the protective cylinder. Several driven bevel gears penetrate the protective cylinder and are rotatably connected to the protective cylinder. Several driven bevel gears are meshed with the driving bevel gear. One end of several driven bevel gears located on the outside of the protective cylinder is fixedly connected to several blades one by one.

[0015] Preferably, the drive shaft has a built-in electromagnetic coil.

[0016] Compared with the prior art, the present invention provides a heat preservation device for frequency converter cabinets on gantry cranes. By setting the heat preservation chamber at the bottom of the top of the gantry, the snow accumulated by the gantry falls on the top of the heat preservation chamber. The heating component is energized and heated to heat the inner cavity of the chamber, so that the electrical components inside the cabinet reach a suitable working temperature, reducing the impact of cold weather on the use of the gantry crane. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 A schematic diagram of the overall structure provided for an embodiment of this utility model;

[0019] Figure 2 A schematic diagram of the insulated chamber and part of the walkway structure provided in an embodiment of this utility model;

[0020] Figure 3A cross-sectional view of the insulated chamber and part of the walkway provided in an embodiment of this utility model;

[0021] Figure 4 A schematic diagram of the bulkhead portion, temperature control assembly, and heating assembly provided for an embodiment of this utility model;

[0022] Figure 5 Partial cross-sectional views of the bulkhead and walkway, and schematic diagram of the overall structure of the perforated plate, temperature control component and heating component provided for embodiments of this utility model;

[0023] Figure 6 This is a cross-sectional schematic diagram of the heating assembly provided in an embodiment of the present utility model;

[0024] Figure 7 A schematic diagram of the one-way vent valve structure provided in this embodiment of the utility model;

[0025] Figure 8 This is a schematic diagram of the temperature control component structure provided in an embodiment of the present utility model;

[0026] Figure 9 Provided for the embodiments of this utility model Figure 8 Enlarged view of A in the middle;

[0027] Figure 10 This is a partial structural diagram of the temperature control component provided in an embodiment of the present utility model;

[0028] Figure 11 This is a partial cross-sectional view of the temperature control component provided in an embodiment of the present utility model;

[0029] Figure 12 This is a schematic diagram showing a partial separation of the temperature control component provided in an embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Gantry; 2. Control Cabin; 3. Insulated Cabin; 4. Ladder; 5. Walkway; 51. Perforated Plate; 6. One-way Vent Valve; 7. Temperature Control Component; 8. Cabinet; 9. Heating Component; 31. Bulkhead; 32. Observation Window; 33. Door; 34. Thermometer; 61. Mounting Ring; 62. Barrier Plate; 63. Limiting Plate; 64. Connecting Rod; 65. Spring; 71. Support Frame; 72. Drive Source; 73. Drive Shaft; 74. Blade; 75. Driven Bevel Gear; 76. Protective Cylinder; 77. Outer Shaft; 78. Spline; 79. Limiting Spring; 710. Slide Rod; 711. Inner Shaft; 712. Driving Bevel Gear; 91. Heat Conducting Plate; 92. Resistance Wire. Detailed Implementation

[0032] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0033] Example 1:

[0034] Please see Figures 1-5 and Figures 8-12 A thermal insulation device for a frequency converter cabinet on a gantry crane includes a gantry 1, an control cabin 2 on one side of the gantry 1, a ladder 4 on one side of the gantry 1 connecting the bottom of the gantry 1 to the control cabin 2, a walkway 5 fixedly connected to the gantry 1 at the bottom of the control cabin 2, and a perforated plate 51 on the side of the walkway 5 away from the control cabin 2. The device also includes a thermal insulation chamber 3, a temperature control component 7, a one-way vent valve 6, and a heating component 9.

[0035] The insulated chamber 3 is located on top of the walkway 5 and at the bottom of the top of the gantry 1;

[0036] Insulated compartment 3 includes:

[0037] The bulkhead 31 is fixedly installed at the bottom of the top of the gantry 1. The bottom of the bulkhead 31 is fixedly connected to the top of the walkway 5. A through hole communicating with the perforated plate 51 is opened through the bottom of the bulkhead 31.

[0038] Thermometer 34 is installed at the top of the inner cavity of bulkhead 31 and is used to monitor the temperature inside the inner cavity of bulkhead 31.

[0039] Temperature control component 7 is located at the bottom of the inner cavity of bulkhead 31 and at the top of the through hole opened in bulkhead 31;

[0040] Temperature control component 7 includes:

[0041] The support frame 71 is located at the bottom of the inner cavity of the bulkhead 31 and above the through hole opened in the bulkhead 31;

[0042] The drive source 72 is fixedly mounted on the top of the support frame 71;

[0043] The drive shaft 73 is fixedly mounted to the output end of the drive source 72 via a coupling;

[0044] Several slide rods 710 are fixedly installed on the end of the drive shaft 73 away from the drive source 72 in a circumferential array.

[0045] An inner shaft 711 is rotatably mounted at the middle of the end of the transmission shaft 73 away from the drive source 72, and the inner shaft 711 is located inside a plurality of slide rods 710;

[0046] Spline 78 is sleeved on the outside of inner shaft 711. Slide rods 710 all pass through spline 78 and are slidably connected to spline 78. Spline 78 can be engaged with inner shaft 711.

[0047] The protective sleeve 76 is fixedly installed at the end of the inner shaft 711 away from the drive source 72;

[0048] Several blades 74 are arranged in a circumferential array on the outside of the protective cylinder 76;

[0049] One-way vent valve 6 is located between orifice plate 51 and protective cylinder 76. One-way vent valve 6 is also located inside the through hole opened at the bottom of bulkhead 31, and is used to control the communication between the inside of bulkhead 31 and the outside.

[0050] Heating assembly 9 is located at the bottom of the inner cavity of bulkhead 31 and above blade 74.

[0051] The specific implementation is as follows: The drive source 72 includes, but is not limited to, a drive motor. The motor is electrically connected to an external power supply and is also controlled by an external PLC programming program. The bulkhead 31 is fixedly connected to the bottom of the top of the gantry 1 by bolts or welding. The gantry 1 partially shelters the bulkhead 31, preventing snow accumulation on the top of the bulkhead 31 in cold, rainy, or snowy weather. The bulkhead 31 is made of thermal insulation material. The bottom of the bulkhead 31 is fixedly installed on the top of the walkway 51. The perforated plate 51 is fixedly installed inside the walkway 51. The perforated plate 51 has several through holes for heat exchange between the inner cavity of the bulkhead 31 and the outside. The thermometer 34 is used to monitor the temperature inside the bulkhead 31. The support frame 71 is open. The support frame 71 is fixed to the bottom of the inner cavity of the bulkhead 31 by bolts or welding. The support frame 71 is located above the perforated plate 51. The top of the support frame 71 is fixedly connected to the drive source 72. The drive source 72 drives the transmission shaft 73 to rotate. The inner shaft 711 is connected to the transmission shaft 73 through the spline 78. When the spline 78 engages with the inner shaft 711, the transmission shaft 73 rotates, causing the inner shaft 711 to rotate. The inner shaft 711 drives the blades 74 on the outside of the protective cylinder 76 to rotate, quickly dispersing the heat generated by the heating component 9 to the inner cavity of the bulkhead 31. When the temperature inside the bulkhead 31 rises and the gas pressure increases, the one-way vent valve 6 opens, connecting the inner cavity of the bulkhead 31 to the outside, releasing the pressure inside the bulkhead 31.

[0052] The insulated chamber 3 also includes a door 33 located on one side of the bulkhead 31. The door 33 is hinged to the bulkhead 31. An observation window 32 is provided on the outer side of the bulkhead 31. The observation window 32 is located on the side close to the walkway 5. A cabinet 81 is provided inside the bulkhead 31. The number of cabinets 81 is not less than one.

[0053] The specific implementation is as follows: the hatch 33 can be manually opened for personnel to enter the inner cavity of the bulkhead 31, the observation window 32 is made of transparent material, the observation window 32 is fixedly installed on the side wall of the bulkhead 31, and the temperature value displayed by the thermometer 34 can be seen through the observation window 32.

[0054] Temperature control component 7 also includes:

[0055] The outer shaft 77 is sleeved on the outside of the inner shaft 711. The outer shaft 77 extends through the inner cavity of the protective cylinder 76. The outer shaft 77 is rotatably connected to the protective cylinder 76. The outer shaft 77 is fixedly connected to the transmission shaft 73 through several slide rods 710.

[0056] A limiting spring 79 is sleeved on the outside of the inner shaft 711 and located on the outside of several slide rods 710. The limiting spring 79 is also located between the spline 78 and the drive shaft 73.

[0057] The driving bevel gear 712 is fixedly installed on the end of the outer shaft 77 away from the transmission shaft 73, and the driving bevel gear 712 is rotatably connected to the inner shaft 711.

[0058] A number of driven bevel gears 75 are arranged in a circumferential array on the circumferential side of the protective cylinder 76. The driven bevel gears 75 all penetrate the protective cylinder 76 and are rotatably connected to the protective cylinder 76. The driven bevel gears 75 are meshed with the driving bevel gear 712. One end of the driven bevel gears 75 located on the outside of the protective cylinder 76 is fixedly connected to a number of blades 74 in a one-to-one correspondence.

[0059] The drive shaft 73 has a built-in electromagnetic coil.

[0060] The specific implementation method is as follows: the limiting spring 79 is an elastic spring, the spline 78 is made of a material that can be attracted by electromagnetic force, the outer shaft 77 can rotate under the drive of the transmission shaft 73, the electromagnetic coil of the transmission shaft 73 is energized, the spline 78 overcomes the elastic force of the limiting spring 79 on the spline 78 under the magnetic attraction, the spline 78 is no longer engaged with the inner shaft 711, the transmission shaft 73 drives the active bevel gear 712 at the end of the outer shaft 77 to rotate, driving the driven bevel gear 75 to rotate, thereby adjusting the angle of the blade 74, after the electromagnetic coil of the transmission shaft 73 is de-energized, the limiting spring 79 pushes the spline 78 to engage with the inner shaft 711, the transmission shaft 73 drives the inner shaft 711 and the protective cylinder 76 to drive the blade 74 to rotate, thereby driving the air flow inside the bulkhead 31.

[0061] Example 2:

[0062] Please see Figures 5-7 This embodiment provides a technical solution based on embodiment one: the heating component 9 includes a heat-conducting plate 91, which is located between the driving source 72 and several blades 74, and a resistance wire 92 is provided on the inner side of the heat-conducting plate 91.

[0063] One-way vent valve 6 includes:

[0064] Mounting ring 61 is fixedly installed on the inner wall of the through hole opened in the bulkhead 31;

[0065] Several connecting rods 64 are fixedly installed at the bottom of the mounting ring 61 in a circular array.

[0066] A limiting plate 63 is fixedly installed at the other end of several connecting rods 64;

[0067] A barrier plate 62 is slidably mounted on the outside of several connecting rods 64;

[0068] Several springs 65 are respectively sleeved on the outside of several connecting rods 64, and the several springs 65 are all located between the barrier plate 62 and the limiting plate 63.

[0069] The specific implementation method is as follows: The resistance wire 92 is an electrothermal resistor. After the resistance wire 92 is energized, it heats up and transfers the heat to the heat-conducting plate 91. The blades 74 rotate and blow air upwards. The heat in the airflow first heats the drive source 72, allowing the drive source 72 to reach the working temperature more quickly. After the resistance wire 92 is energized, it heats up and transfers the heat to the air inside the cavity of the bulkhead 31 through the heat-conducting plate 91. The rotation of the blades 74 generates airflow, which helps to evenly distribute the heat and heat the cavity inside the bulkhead 31. When the temperature inside the cavity of the bulkhead 31 rises to a suitable temperature for the electrical components inside the cabinet 8 to operate, the resistance wire 92 stops working. When the temperature inside the cavity of the bulkhead 31 is higher than the suitable working temperature for the electrical components inside the cabinet 8, and the temperature inside the cavity of the bulkhead 31... As the air expands due to the upward movement, and the inner cavity of the bulkhead 31 is closed, the gas pressure increases. When the gas pressure exceeds the elastic force of the spring 65 on the baffle plate 62, the baffle plate 62 moves downward and separates from the mounting ring 61, allowing outside air to communicate with the inner cavity of the bulkhead 31. When the gas pressure inside the bulkhead 31 exceeds the elastic force of the spring 65 on the baffle plate 62, the baffle plate 62 moves downward and separates from the mounting ring 61, allowing the high-temperature air inside the bulkhead 31 to be discharged through the one-way vent valve 6 under the action of the pressure difference. At the same time, the tilt angle adjustment of the blade 74 can affect the flow direction and speed of the airflow inside the bulkhead 31, which helps to dissipate heat and regulate the temperature inside the bulkhead 31, thereby maintaining and regulating the temperature inside the bulkhead 31.

[0070] Working principle: When in use, in cold weather, the heating component 9 starts to work, the resistance wire 92 is energized and heats up, and the heat is transferred to the air inside the cavity of the bulkhead 31 and the drive source 72 through the heat conduction plate 91.

[0071] The temperature control component 7 adjusts the angle and rotation speed of the blade 74 based on the monitoring results of the thermometer 34 (this part belongs to the prior art and is not described in detail) to achieve uniform heat distribution and stable temperature control.

[0072] When the temperature inside the bulkhead 31 rises to a suitable operating temperature for the electrical components inside the cabinet 8, the resistance wire 92 stops working. If the temperature inside the bulkhead 31 continues to rise and exceeds the suitable operating temperature, the one-way vent valve 6 will automatically open to release internal pressure and expel high-temperature air.

[0073] The bulkhead 31, hatch 33, and observation window 32 of the insulated chamber 3 work together to maintain a constant temperature environment inside the bulkhead 31, ensuring the normal operation of electrical components under extreme climatic conditions.

[0074] The bulkhead 31 and hatch 33 of the insulated chamber 3 work together to maintain a constant temperature environment inside the bulkhead 31.

[0075] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A heat preservation device for a frequency converter cabinet on a gantry crane, the gantry crane including a main beam (1), gantry legs symmetrically fixedly installed at the bottom of the main beam (1), an control cabin (2) provided on one side of the bottom of the main beam (1), the control cabin (2) being located on one side of the gantry legs, a ladder (4) connected to the control cabin (2) being provided at the bottom of the gantry legs, the ladder (4) being fixedly connected to the gantry legs, a walkway (5) fixedly connected to the gantry legs being provided at the bottom of the control cabin (2), and a perforated plate (51) being provided at the bottom of the side of the walkway (5) away from the control cabin (2), characterized in that, A heat preservation device is installed on the side of the walkway (5) away from the control cabin (2). The heat preservation device includes a heat preservation chamber (3), a temperature control component (7), a one-way vent valve (6), and a heating component (9). The insulated chamber (3) is set on the top of the walkway (5) and located at the bottom of the main beam (1). The insulated chamber (3) includes a chamber wall (31) and a thermometer (34). The chamber wall (31) is a cuboid structure. The top of the chamber wall (31) is fixedly installed at the bottom of the main beam (1). The bottom of the chamber wall (31) is fixedly connected to the top of the walkway (5). The bottom of the chamber wall (31) has a through hole that communicates with the perforated plate (51). The thermometer (34) is set on the top of the inner cavity of the chamber wall (31). The temperature control component (7) is located at the bottom of the inner cavity of the bulkhead (31) and above the through hole at the bottom of the bulkhead (31). The temperature control component (7) includes a support frame (71), a drive source (72), a transmission shaft (73), blades (74), a protective cylinder (76), a spline (78), a slide rod (710), and an inner shaft (711). The bottom of the support frame (71) is located at the bottom of the inner cavity of the bulkhead (31) and above the through hole at the bottom of the bulkhead (31). The drive source (72) is fixedly installed on the top of the support frame (71). The transmission shaft (73) is fixedly installed at the output end of the bottom of the drive source (72) through a coupling. Several slide rods are also included. The upper end of the rod (710) is fixedly installed at the bottom of the transmission shaft (73) in a circumferential array. The upper end of the inner shaft (711) is rotatably installed at the middle position of the bottom of the transmission shaft (73) and the inner shaft (711) is located inside the several sliding rods (710). The spline (78) is sleeved on the outer side of the lower end of the inner shaft (711). The lower end of the sliding rod (710) passes through the spline (78) and is slidably connected with the spline (78). The spline (78) is snapped into the inner shaft (711). The protective cylinder (76) is fixedly installed at the bottom of the inner shaft (711). Several blades (74) are arranged in a circumferential array on the outer side of the protective cylinder (76). The one-way ventilation valve (6) is located inside the through hole opened at the bottom of the bulkhead (31) and at the top of the perforated plate (51); The heating component (9) is located on one side of the support frame (71).

2. The heat preservation device applied to the variable frequency cabinet on the gantry crane according to claim 1, characterized in that, The insulated chamber (3) also includes a door (33) located on one side of the bulkhead (31), the door (33) being hinged to the bulkhead (31), an observation window (32) being provided on the outer side of the bulkhead (31), the observation window (32) being located on the side near the walkway (5), and a cabinet (81) being provided in the inner cavity of the bulkhead (31), the number of cabinets (81) being not less than one.

3. The heat preservation device applied to the variable frequency cabinet on the gantry crane according to claim 1, characterized in that, The heating assembly (9) includes a heat-conducting plate (91), which is located on a horizontal plane between the driving source (72) and a plurality of blades (74), and a resistance wire (92) is provided on the inner side of the heat-conducting plate (91).

4. The heat preservation device applied to the variable frequency cabinet on the gantry crane according to claim 1, characterized in that, The one-way ventilation valve (6) includes an installation ring (61), a baffle plate (62), a limiting plate (63), a connecting rod (64), and a spring (65). The installation ring (61) is fixedly installed on the inner wall of the through hole opened in the bulkhead (31). The tops of several connecting rods (64) are arranged in a circular array and fixedly installed on the bottom of the installation ring (61). The bottoms of several connecting rods (64) are fixedly installed on the top of the limiting plate (63). The spring (65) is sleeved on the outside of the connecting rod (64). The connecting rod (64) passes through the baffle plate (62) so that the baffle plate (62) slides up and down along the connecting rod (64). The spring (65) is located between the baffle plate (62) and the limiting plate (63).

5. The heat preservation device applied to the variable frequency cabinet on the gantry crane according to claim 1, characterized in that, The temperature control assembly (7) also includes a driven bevel gear (75), an outer shaft (77), a limiting spring (79), and a driving bevel gear (712); An outer shaft (77) is sleeved on the outside of the inner shaft (711) at the lower part of the spline (78). The outer shaft (77) extends through the inner cavity of the protective cylinder (76). The outer shaft (77) is rotatably connected to the protective cylinder (76). The top of the outer shaft (77) is fixedly connected to the drive shaft (73) via a slide rod (710). A limiting spring (79) is sleeved on the outside of the slide rod (710) and is located between the spline (78) and the drive shaft (73). A driving bevel gear (712) is fixedly installed at the bottom of the outer shaft (77). 712) is rotatably connected to the inner shaft (711), and the outer shaft (77) is rotatably connected to the inner shaft (711); a plurality of driven bevel gears (75) are distributed in a circumferential array on the circumferential side of the inner wall of the protective cylinder (76), a plurality of driven bevel gears (75) penetrate the protective cylinder (76) and are rotatably connected to the protective cylinder (76), a plurality of driven bevel gears (75) are meshed with the driving bevel gear (712), and one end of a plurality of driven bevel gears (75) located outside the protective cylinder (76) is fixedly connected to a plurality of blades (74) one by one.

6. The heat preservation device applied to the variable frequency cabinet on the gantry crane according to claim 1, characterized in that, The drive shaft (73) has a built-in electromagnetic coil.

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