A vibration testing device and method for a tower crane boom

Abstract

The present invention discloses a vibration testing device and method for a tower crane boom, including a fixed disk and a bottom plate. Above the fixed disk, there is a rotating arm, and the rotating arm is movably installed in the middle of the fixed disk through a movable mechanism. At both ends near the bottom of the rotating arm, there is an electromagnetic block respectively, and a plurality of magnetic attraction blocks matching the electromagnetic blocks are evenly distributed on the upper end of the fixed disk. At the upper end of the rotating arm, there are three groups of acceleration sensors, and below the fixed disk, there is a rotating mechanism for driving the rotating arm to rotate. In the present invention, different vibration data can be received by the three acceleration sensors, and the data difference between two adjacent acceleration sensors can be obtained. By calculating multiple groups of data, the position of the vibration source can be obtained; the rotating arm is driven to rotate by the rotating mechanism, so that the three groups of acceleration sensors at the upper end of the rotating arm change the measurement position and angle, and the vibration measurement is carried out again through the three groups of acceleration sensors, making the vibration measurement more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration measurement, and particularly relates to a vibration testing device and method for a tower crane boom. Background Art

[0002] Tower cranes play a crucial role in modern construction. As a key load-bearing component, the boom of a tower crane bears various complex loads during the process of lifting heavy objects, such as its own gravity, the weight of the heavy object, wind force, inertial forces generated by hoisting and luffing motions, etc. This is very likely to cause serious problems such as fatigue damage of the boom and loosening of the connection parts. If the vibration amplitude of the boom is too large or the frequency is in the dangerous range, it may even cause the boom to break, thereby endangering the safe operation of the entire tower crane and the safety of construction site personnel and equipment.

[0003] Currently, there are many defects in the testing devices and methods for the vibration of tower crane booms. For example, sticking strain gauges on the surface of the boom and installing acceleration sensors. Although some vibration information can be obtained, due to the long size of the boom, it is very difficult to accurately obtain the position of the vibration source, resulting in deviations in the measurement results. Therefore, there is an urgent need to develop a vibration testing device and method for tower crane booms. Summary of the Invention

[0004] The purpose of the present invention is to provide a vibration testing device for a tower crane boom to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A vibration testing device for a tower crane boom, including a fixed disk and a bottom plate. The bottom plate is located below the fixed disk. The fixed disk is fixed to the upper end of the boom, and the bottom plate is fixed to the square tube in the middle of the boom. A rotating arm is provided above the fixed disk, and the rotating arm is movably installed in the middle of the fixed disk through a movable mechanism;

[0006] At both ends close to the bottom of the rotating arm, there is an electromagnetic block respectively. The electromagnetic block is controlled to be energized or de-energized through an electromagnetic control mechanism. A plurality of magnetic attraction blocks matching the electromagnetic blocks are evenly distributed on the upper end of the fixed disk, and after the electromagnetic block is energized, it magnetically attracts with the magnetic attraction block;

[0007] Three groups of acceleration sensors are provided at the upper end of the rotating arm, and the three groups of acceleration sensors are evenly distributed on the rotating arm in a line;

[0008] A rotating mechanism for driving the rotating arm to rotate is provided below the fixed disk, and the rotating mechanism is installed on the bottom plate.

[0009] Preferably, the movable mechanism includes a movable shaft. A plurality of balls are evenly distributed on the outer diameter of the movable shaft near the middle, and the balls are in rolling connection with the movable shaft;

[0010] A fixing ring is provided in the middle of the fixing plate, and the ball is also in rolling connection with the inner diameter of the fixing ring.

[0011] Preferably, the rotating mechanism includes a large gear rotatably installed at the upper end of the bottom plate. The large gear is meshed with a small gear, and the small gear is driven to rotate by a motor.

[0012] A fixing frame one is provided at the upper end of the large gear. A square shaft is slidably connected up and down at the upper end of the fixing frame one, and the square shaft is driven to lift by a telescopic rod.

[0013] A square block is fixedly connected to the lower end of the movable shaft. The square shaft is located below the square block, and there is a gap between the square shaft and the square block.

[0014] A square hole matching the square shaft is provided at the bottom of the square block. The square shaft is driven by a telescopic rod to insert into or leave the square hole.

[0015] Guide columns one for cooperating with the lifting of the square shaft are provided on both sides of the square shaft. The guide columns one are slidably connected up and down with the fixing frame one.

[0016] Preferably, the electromagnetic control mechanism includes a pressure sensor and a fixing frame two located on one side of the square block. The pressure sensor is located inside the fixing frame two. A guide column two is slidably connected to one side of the fixing frame two. A pressing block is provided at one end of the guide column two. The pressing block is located inside the fixing frame two and abuts against the pressure sensor. A bearing block is provided at the other end of the guide column two. The bearing block is located outside the fixing frame two. A return spring for resetting the pressing block is sleeved on the outside of the guide column two. The return spring is located between the fixing frame two and the bearing block.

[0017] An extrusion block for extruding the bearing block is provided at the upper end of the guide column one on the same side as the pressure sensor, and the side of the extrusion block close to the bearing block is triangular in shape.

[0018] After the pressure sensor is squeezed, the electromagnetic block is powered on or off.

[0019] Preferably, a cleaning mechanism for cleaning the magnetic attraction block is provided above the fixing plate. There are two groups of cleaning mechanisms, and the two groups of cleaning mechanisms are respectively located on different sides at both ends of the rotating arm.

[0020] Preferably, the cleaning mechanism includes a fixing plate located on one side of the electromagnetic block. The fixing plate forms an angle with the rotating arm, and one end of the fixing plate is fixedly connected to the middle of the rotating arm.

[0021] A cleaning roller is rotatably installed at the bottom of one end of the fixing plate, and the height of the cleaning roller is lower than that of the magnetic attraction block. Cleaning brushes are evenly distributed on the surface of the cleaning roller.

[0022] A plurality of friction tracks corresponding to the magnetic attraction blocks are provided at positions close to the edge of the fixed disk. One end of the cleaning roller is connected with a friction wheel matching the friction track through a rotating shaft. When the friction wheel passes through the friction track, the friction wheel rotates to clean the magnetic attraction blocks.

[0023] Preferably, the friction track is of an arc structure, and inclined surfaces are provided at both ends of the friction track.

[0024] Preferably, there are four groups of the electromagnetic blocks and the magnetic attraction blocks, and the number of each group is two.

[0025] Preferably, a plurality of through grooves penetrating through the fixed disk itself are provided on the fixed disk, and the through grooves and the magnetic attraction blocks are distributed at intervals.

[0026] A vibration test method for a tower crane boom, used in cooperation with a vibration test device for a tower crane boom, includes the following steps:

[0027] S1. Install at least three groups of this test device on the boom of the tower crane and arrange them evenly in a line, so that the fixed disk is installed at the upper end of the boom and the bottom plate is installed on the square tube in the middle of the boom;

[0028] S2. Electrify the two electromagnetic blocks at the bottom of the slewing arm to generate magnetism, and adsorb on the magnetic attraction blocks through magnetism to fix the slewing arm. When a large vibration occurs at a certain part of the boom, it will be sequentially conducted to the three acceleration sensors. Since the distances of the three acceleration sensors from the vibration source are different, the vibration data received are also different, and the data difference between two adjacent acceleration sensors can be obtained. Similarly, the three acceleration sensors on another group of this test device close to the vibration source will also receive vibration data and obtain the data difference between two adjacent acceleration sensors. By calculating the two groups of data, the position of the vibration source can be obtained;

[0029] S3. When it is detected that the vibration of the boom is abnormal, drive the square shaft to rise through the telescopic rod so that it is inserted into the square hole, and then drive the square shaft and the slewing arm to rotate a certain angle through the rotating mechanism, so that the electromagnetic block and the magnetic attraction blocks of another group adsorb each other, so that the three acceleration sensors at the upper end of the slewing arm change the measurement position and angle, and perform vibration measurement again through the three acceleration sensors. Four vibration measurements at different positions and angles can be carried out in sequence, and four groups of data can be obtained, making the vibration measurement more accurate;

[0030] S4. After the test is completed, turn off the motor, and the telescopic rod drives the square shaft to leave the square hole.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] In the present invention, three acceleration sensors are arranged in a line. Since the distances of the three acceleration sensors from the vibration source are different, the vibration data received by them are also different, and the data difference between two adjacent acceleration sensors can be obtained. Similarly, another set of three acceleration sensors on this test device close to the vibration source will also receive vibration data and obtain the data difference between two adjacent acceleration sensors. By calculating the two sets of data, the position of the vibration source can be obtained;

[0033] The rotating mechanism drives the rotating arm to rotate, so that the three groups of acceleration sensors at the upper end of the rotating arm change the measurement positions and angles, and the vibration measurement is carried out again by the three groups of acceleration sensors. The vibration measurement at four positions and angles can be carried out in sequence, four sets of data can be obtained, the vibration measurement is more accurate, and the position of the vibration source obtained is more accurate;

[0034] The electromagnetic control mechanism can energize and de-energize the electromagnetic block, which is convenient for controlling the electromagnetic block, so that the electromagnetic block and the magnetic absorption block are adsorbed or separated;

[0035] The cleaning mechanism can clean the dust on the upper end of the magnetic absorption block to prevent too much dust on the magnetic absorption block from affecting the adsorption effect between the electromagnetic block and the magnetic absorption block. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of the overall structure of the present invention Figure 1 ;

[0037] Figure 2 is a schematic diagram of the overall structure of the present invention Figure 2 ;

[0038] Figure 3 is a front view of the present invention;

[0039] Figure 4 is a front sectional view of the present invention;

[0040] Figure 5 is of the present invention Figure 4 detailed enlarged view at A;

[0041] Figure 6 is a schematic diagram of the vibration measurement principle of the present invention.

[0042] In the figure: 1. Fixed disk; 2. Base plate; 3. Rotating arm; 4. Moving mechanism; 41. Moving shaft; 42. Ball; 43. Fixed ring; 5. Electromagnetic block; 51. Magnetic attraction block; 6. Electromagnetic control mechanism; 61. Pressure sensor; 62. Second fixing bracket; 63. Second guide post; 64. Pressing block; 65. Bearing block; 66. Return spring; 67. Extrusion block; 7. Acceleration sensor; 8. Rotating mechanism; 81. Motor; 82. Small gear; 83. Large gear; 84. First fixing bracket; 85. Square shaft; 86. Telescopic rod; 87. Square block; 88. Square hole; 89. First guide post; 9. Cleaning mechanism; 91. Fixing plate; 92. Cleaning roller; 93. Friction track; 94. Friction wheel; 10. Through groove. Detailed implementation manners

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0044] Please refer to Figures 1-6 , the present invention provides a technical solution: a vibration testing device for a tower crane boom, including a fixed disk 1 and a base plate 2. The base plate 2 is located below the fixed disk 1. The fixed disk 1 is provided with a plurality of through grooves 10 penetrating through itself. The through grooves 10 and the magnetic attraction blocks 51 are distributed at intervals. The fixed disk 1 is fixed to the upper end of the boom, and the base plate 2 is fixed to the square tube in the middle of the boom. Above the fixed disk 1 is provided a rotating arm 3. The rotating arm 3 is movably installed in the middle of the fixed disk 1 through a moving mechanism 4. The moving mechanism 4 includes a moving shaft 41. A plurality of balls 42 are evenly distributed on the outer diameter of the moving shaft 41 near the middle. The balls 42 are in rolling connection with the moving shaft 41. A fixed ring 43 is provided in the middle of the fixed disk 1. The balls 42 are also in rolling connection with the inner diameter of the fixed ring 43.

[0045] Among them, the moving shaft 41 rolls in the fixed ring 43 in the middle of the fixed disk 1 through the balls 42, so that the rotating arm 3 can rotate and lift relative to the fixed disk 1.

[0046] At both ends near the bottom of the rotating arm 3, an electromagnetic block 5 is provided. The electromagnetic block 5 is controlled to be energized or de-energized through an electromagnetic control mechanism 6. A plurality of magnetic attraction blocks 51 matching the electromagnetic blocks 5 are evenly distributed on the upper end of the fixed disk 1. And after the electromagnetic block 5 is energized, it magnetically attracts the magnetic attraction block 51. There are four groups of electromagnetic blocks 5 and magnetic attraction blocks 51, and the number of each group is two. Three groups of acceleration sensors 7 are provided at the upper end of the rotating arm 3, and the three groups of acceleration sensors 7 are evenly distributed in a line on the rotating arm 3. Below the fixed disk 1 is provided a rotating mechanism 8 for driving the rotating arm 3 to rotate. The rotating mechanism 8 is installed on the base plate 2.

[0047] When conducting the test, at least three groups of this test device are installed on the boom of the tower crane and arranged evenly in a line, such that the fixed plate 1 is installed at the upper end of the boom, and the bottom plate 2 is installed on the square tube in the middle of the boom. The two electromagnetic blocks 5 at the bottom of the rotating arm 3 are electrified to generate magnetism, and are magnetically adsorbed on the magnetic absorption block 51, so that the rotating arm 3 is in a fixed state. When a large vibration occurs at a certain part of the boom, it will be transmitted to the three acceleration sensors 7 in sequence. Since the three acceleration sensors 7 are at different distances from the vibration source, the vibration data received are also different, and the data difference between two adjacent acceleration sensors 7 can be obtained. Similarly, the three acceleration sensors 7 on another group of this test device closer to the vibration source will also receive vibration data and obtain the data difference between two adjacent acceleration sensors 7. By calculating the two groups of data, the position of the vibration source can be obtained. For example, as Figure 6 , the three acceleration sensors 7 at A are closer to the vibration source, and the three acceleration sensors 7 at B are relatively farther from the vibration source. After A and B receive the vibration data of the vibration source, the vibration data differences of the three adjacent acceleration sensors 7 at A and B are calculated respectively. According to the data differences at A and B, the position of A1 can be calculated, that is, the distance from A1 to the vibration source is the same as the distance from A to the vibration source. Therefore, the approximate position of the vibration source can be obtained. Then, the rotating mechanism 8 drives the square shaft 85 and the rotating arm 3 to rotate a certain angle, so that the electromagnetic block 5 and the magnetic absorption block 51 of another group are mutually adsorbed, causing the three acceleration sensors 7 at the upper end of the rotating arm 3 to change the measurement position and angle, and the vibration measurement is carried out again through the three acceleration sensors 7. The vibration measurement at four positions and angles can be carried out in sequence, four groups of data can be obtained, the vibration measurement is more accurate, and the position of the vibration source obtained is more accurate;

[0048] The rotating mechanism 8 includes a large gear 83 rotatably installed at the upper end of the bottom plate 2. The large gear 83 is meshed and connected with a small gear 82. The small gear 82 is driven to rotate by a motor 81. A fixing frame one 84 is provided at the upper end of the large gear 83. A square shaft 85 is slidably connected up and down at the upper end of the fixing frame one 84. The square shaft 85 is driven to lift by a telescopic rod 86. A square block 87 is fixedly connected to the lower end of the movable shaft 41. The square shaft 85 is located below the square block 87, and there is a gap between the square shaft 85 and the square block 87. A square hole 88 matching the square shaft 85 is provided at the bottom of the square block 87. The square shaft 85 is driven by the telescopic rod 86 to insert into or leave the square hole 88. Guide columns one 89 for cooperating with the lifting of the square shaft 85 are provided on both sides of the square shaft 85. The guide columns one 89 are slidably connected up and down with the fixing frame one 84.

[0049] During operation, the telescopic rod 86 drives the square shaft 85 to rise, causing the square shaft 85 to insert into the square hole 88 at the bottom of the square block 87. Then, the electromagnetic control mechanism 6 cuts off the power supply to the electromagnetic block 5, so that the electromagnetic block 5 and the magnetic attraction block 51 no longer attract each other. At the same time, the square shaft 85 continues to rise, causing the rotating arm 3 to be lifted, so that the electromagnetic block 5 leaves the magnetic attraction block 51. Then, the motor 81 drives the small gear 82 to rotate, causing the large gear 83 to rotate. Through the fixed frame one 84, the square shaft 85, the square block 87 and the movable shaft 41, the rotating arm 3 rotates. Since the electromagnetic block 5 leaves the magnetic attraction block 51, there will be no friction between the two. When the two electromagnetic blocks 5 at the bottom of the rotating arm 3 correspond to the next group of magnetic attraction blocks 51, the motor 81 stops running. Then, the telescopic rod 86 drives the square shaft 85 to descend, causing the rotating arm 3 to descend. The electromagnetic control mechanism 6 supplies power to the electromagnetic block 5, so that the electromagnetic block 5 and the magnetic attraction block 51 attract each other again. The rotating arm 3 is fixed at the upper end of the fixed disk 1. Therefore, the three acceleration sensors 7 at the upper end of the rotating arm 3 change their positions and angles, and can perform vibration tests again. In this way, 8 groups of different vibration data can be tested.

[0050] The electromagnetic control mechanism 6 includes a pressure sensor 61 located on one side of the square block 87 and a fixed frame two 62. The pressure sensor 61 is located inside the fixed frame two 62. A guide post two 63 is slidably connected to one side of the fixed frame two 62. One end of the guide post two 63 is provided with a pressing block 64. The pressing block 64 is located inside the fixed frame two 62 and abuts against the pressure sensor 61. The other end of the guide post two 63 is provided with a bearing block 65. The bearing block 65 is located outside the fixed frame two 62. A return spring 66 for resetting the pressing block 64 is sleeved on the outside of the guide post two 63. The return spring 66 is located between the fixed frame two 62 and the bearing block 65. The upper end of the guide post one 89 on the same side as the pressure sensor 61 is provided with a pressing block 67 for pressing the bearing block 65. The side of the pressing block 67 close to the bearing block 65 is triangular in shape. After the pressure sensor 61 is pressed, the electromagnetic block 5 is powered on or off.

[0051] During operation, the telescopic rod 86 drives the square shaft 85 to rise, causing the guide posts 89 on both sides of the square shaft 85 to rise, and then the extrusion block 67 to rise. After the square shaft 85 is inserted into the square hole 88, the extrusion block 67 squeezes the bearing block 65 upward, causing the bearing block 65 to approach the pressure sensor 61. Through the guide post 63, the pressing block 64 squeezes the pressure sensor 61. After being squeezed, the pressure sensor 61 transmits a signal to the controller of the electromagnetic block 5, and then the power supply of the electromagnetic block 5 is cut off, so that the electromagnetic block 5 and the magnetic attraction block 51 no longer attract each other, enabling the electromagnetic block 5 to leave the magnetic attraction block 51, allowing the rotating arm 3 to rise and rotate. When the extrusion block 67 leaves the bearing block 65, the pressing block 64 returns to its original position under the action of the return spring 66 and no longer squeezes the pressure sensor 61. When the rotating arm 3 rotates to the specified position, when the telescopic rod 86 drives the square shaft 85 to descend, the extrusion block 67 squeezes the bearing block 65 downward, causing the pressing block 64 to squeeze the pressure sensor 61 again. At this time, after receiving the signal, the electromagnetic block 5 is powered on, enabling the electromagnetic block 5 and the magnetic attraction block 51 to attract each other, thereby fixing the rotating arm 3 again.

[0052] Above the fixed disk 1, there is a cleaning mechanism 9 for cleaning the magnetic attraction block 51. There are two groups of cleaning mechanisms 9, and the two groups of cleaning mechanisms 9 are respectively located on different sides at both ends of the rotating arm 3. The cleaning mechanism 9 includes a fixing plate 91 on one side of the electromagnetic block 5. The fixing plate 91 forms an angle with the rotating arm 3, and one end of the fixing plate 91 is fixedly connected to the middle of the rotating arm 3. At the bottom of one end of the fixing plate 91, a cleaning roller 92 is rotatably installed, and the height of the cleaning roller 92 is lower than that of the magnetic attraction block 51. Cleaning brushes are evenly distributed on the surface of the cleaning roller 92. Near the edge of the fixed disk 1, there are a plurality of friction tracks 93 corresponding to the magnetic attraction blocks 51. The friction tracks 93 are arc-shaped structures, and inclined surfaces are provided at both ends of the friction tracks 93. One end of the cleaning roller 92 is connected by a rotating shaft to a friction wheel 94 that matches the friction track 93. When the friction wheel 94 passes through the friction track 93, the friction wheel 94 rotates to clean the magnetic attraction block 51.

[0053] Among them, since the tower crane is used on the construction site, dust will be generated on the upper end of the magnetic attraction block 51. If there is too much dust, it will affect the adsorption effect between the electromagnetic block 5 and the magnetic attraction block 51. Therefore, the cleaning mechanism 9 can clean the dust on the upper end of the magnetic attraction block 51. When the rotating arm 3 rotates, the fixing plate 91 will move accordingly, causing the cleaning roller 92 to move with the fixing plate 91. When the cleaning roller 92 approaches the magnetic attraction block 51, the outer diameter of the friction wheel 94 will contact the friction track 93. Due to the frictional force, the friction wheel 94 rolls on the friction track 93, causing the cleaning roller 92 to rotate, so that the cleaning brushes on the cleaning roller 92 can clean the dust on the magnetic attraction block 51.

[0054] A vibration testing method for a tower crane boom, which is used in conjunction with a vibration testing device for a tower crane boom, includes the following steps:

[0055] S1. Install at least three groups of this test device on the boom of the tower crane and arrange them evenly in a line, so that the fixed disk 1 is installed at the upper end of the boom, and the bottom plate 2 is installed on the square tube in the middle of the boom;

[0056] S2. Energize the two electromagnetic blocks 5 at the bottom of the rotating arm 3 to generate magnetism, and adsorb them on the magnetic absorption block 51 through magnetism, so that the rotating arm 3 is in a fixed state. When a large vibration occurs at a certain part of the boom, it will be sequentially transmitted to the three acceleration sensors 7. Since the three acceleration sensors 7 are at different distances from the vibration source, the vibration data received are also different, and the data difference between two adjacent acceleration sensors 7 can be obtained. Similarly, the three acceleration sensors 7 on another group of this test device close to the vibration source will also receive vibration data and obtain the data difference between two adjacent acceleration sensors 7. The position of the vibration source can be obtained by calculating the two groups of data;

[0057] S3. When the abnormal vibration of the boom is detected, drive the square shaft 85 to rise through the telescopic rod 86 so that it is inserted into the square hole 88, and then drive the square shaft 85 and the rotating arm 3 to rotate a certain angle through the rotating mechanism 8, so that the electromagnetic block 5 and the magnetic absorption block 51 of another group are adsorbed to each other, so that the three acceleration sensors 7 at the upper end of the rotating arm 3 change the measurement position and angle, and the vibration measurement is carried out again through the three acceleration sensors 7. The vibration measurement can be carried out at four positions and angles in sequence, and four groups of data can be obtained, making the vibration measurement more accurate;

[0058] S4. After the test is completed, turn off the motor 81, and the telescopic rod 86 drives the square shaft 85 to leave the square hole 88.

[0059] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A vibration test device for a tower crane boom, comprising a fixed disk (1) and a bottom plate (2), the bottom plate (2) is located below the fixed disk (1), the fixed disk (1) is fixed to the upper end of the boom, and the bottom plate (2) is fixed to the square tube in the middle of the boom, characterized in that: Above the fixed disk (1), there is a rotating arm (3), and the rotating arm (3) is movably installed in the middle of the fixed disk (1) through a moving mechanism (4); At both ends close to the bottom of the rotating arm (3), there is an electromagnet block (5) respectively. The electromagnet block (5) is controlled to be energized or de-energized through an electromagnetic control mechanism (6). A plurality of magnetic attraction blocks (51) matching the electromagnet block (5) are evenly distributed on the upper end of the fixed disk (1). After the electromagnet block (5) is energized, it magnetically attracts with the magnetic attraction block (51); At the upper end of the rotating arm (3), there are three groups of acceleration sensors (7), and the three groups of acceleration sensors (7) are evenly distributed on the rotating arm (3) in a line; Below the fixed disk (1), there is a rotating mechanism (8) for driving the rotation of the rotating arm (3), and the rotating mechanism (8) is installed on the bottom plate (2); Among them, the rotating mechanism (8) includes a large gear (83) rotatably installed on the upper end of the bottom plate (2). The large gear (83) is meshed with a small gear (82). The small gear (82) is driven to rotate by a motor (81). At the upper end of the large gear (83), there is a fixing bracket one (84). The upper end of the fixing bracket one (84) is slidably connected with a square shaft (85) up and down. The square shaft (85) is driven to lift by a telescopic rod (86). The bottom of the moving mechanism (4) is fixedly connected with a square block (87). The square shaft (85) is located below the square block (87), and there is a gap between the square shaft (85) and the square block (87). A square hole (88) matching the square shaft (85) is provided at the bottom of the square block (87). The square shaft (85) is driven by the telescopic rod (86) to insert into or leave the square hole (88). On both sides of the square shaft (85), there are guide columns one (89) for cooperating with the lifting of the square shaft (85). The guide columns one (89) are slidably connected with the fixing bracket one (84) up and down; Among them, the electromagnetic control mechanism (6) includes a pressure sensor (61) and a fixing bracket two (62) located on one side of the square block (87). The pressure sensor (61) is located inside the fixing bracket two (62). One side of the fixing bracket two (62) is slidably connected with a guide column two (63). One end of the guide column two (63) is provided with a pressing block (64). The pressing block (64) is located inside the fixing bracket two (62) and abuts against the pressure sensor (61). The other end of the guide column two (63) is provided with a bearing block (65). The bearing block (65) is located outside the fixing bracket two (62). A return spring (66) for resetting the pressing block (64) is sleeved outside the guide column two (63). The return spring (66) is located between the fixing bracket two (62) and the bearing block (65). At the upper end of the guide column one (89) on the same side as the pressure sensor (61), there is an extrusion block (67) for extruding the bearing block (65). The side of the extrusion block (67) close to the bearing block (65) is triangular. After the pressure sensor (61) is extruded, the electromagnet block (5) is energized or de-energized.

2. The vibration test device for a tower crane boom according to claim 1, characterized in that: The movable mechanism (4) includes a movable shaft (41). A plurality of balls (42) are evenly distributed on the outer diameter of the movable shaft (41) near the middle. The balls (42) are in rolling connection with the movable shaft (41). A fixed ring (43) is provided in the middle of the fixed disk (1). The balls (42) are also in rolling connection with the inner diameter of the fixed ring (43).

3. The vibration test device for a tower crane boom according to claim 1, characterized in that: A cleaning mechanism (9) for cleaning the magnetic attraction blocks (51) is provided above the fixed disk (1). There are two groups of the cleaning mechanisms (9), and the two groups of cleaning mechanisms (9) are respectively located on different sides at both ends of the rotating arm (3).

4. A vibration test device for a tower crane boom according to claim 3, characterized in that: The cleaning mechanism (9) includes a fixing plate (91) on one side of the electromagnetic block (5). The fixing plate (91) forms an angle with the rotating arm (3), and one end of the fixing plate (91) is fixedly connected to the middle of the rotating arm (3). A cleaning roller (92) is rotatably installed at the bottom of one end of the fixing plate (91), and the height of the cleaning roller (92) is lower than that of the magnetic attraction block (51). Cleaning brushes are evenly distributed on the surface of the cleaning roller (92). A plurality of friction tracks (93) corresponding to the magnetic attraction blocks (51) are provided near the edge of the fixed disk (1). One end of the cleaning roller (92) is connected by a rotating shaft to a friction wheel (94) matching the friction track (93). When the friction wheel (94) passes through the friction track (93), the friction wheel (94) rotates to clean the magnetic attraction block (51).

5. The vibration test device for a tower crane boom according to claim 4, characterized in that: The friction track (93) is of an arc structure, and inclined surfaces are provided at both ends of the friction track (93).

6. The vibration testing device for a tower crane boom according to claim 1, wherein: There are four groups of the electromagnetic blocks (5) and the magnetic attraction blocks (51), and the number of each group is two.

7. The vibration test device for a tower crane boom according to claim 1, characterized in that: A plurality of through grooves (10) penetrating through itself are provided on the fixed disk (1), and the through grooves (10) and the magnetic attraction blocks (51) are distributed at intervals.

8. A vibration test method for a tower crane boom, which is used in conjunction with the vibration test device for a tower crane boom according to any one of claims 1-7, characterized in that, It includes the following steps: S1. Install at least three groups of this test device on the boom of the tower crane and arrange them evenly in a line, so that the fixed disk (1) is installed at the upper end of the boom, and the bottom plate (2) is installed on the square pipe in the middle of the boom. S2. Energize the two electromagnetic blocks (5) at the bottom of the rotating arm (3) to generate magnetism, and magnetically adsorb on the magnetic attraction blocks (51) to fix the rotating arm (3). When a large vibration occurs at a certain part of the boom, it will be transmitted to the three acceleration sensors (7) in sequence. Since the three acceleration sensors (7) are at different distances from the vibration source, the vibration data received are different, and the data difference between two adjacent acceleration sensors (7) can be obtained. Similarly, the three acceleration sensors (7) on another group of this test device close to the vibration source will also receive vibration data and obtain the data difference between two adjacent acceleration sensors (7). The position of the vibration source can be obtained by calculating the two groups of data. S3. When abnormal vibration of the boom is detected, the telescopic rod (86) drives the square shaft (85) to rise and insert into the square hole (88). Then, the rotation mechanism (8) drives the square shaft (85) and the rotating arm (3) to rotate by a certain angle, so that the electromagnetic block (5) and the magnetic attraction blocks (51) of the other group are mutually attracted, causing the three acceleration sensors (7) at the upper end of the rotating arm (3) to change the measurement positions and angles, and the vibration is measured again through the three acceleration sensors (7). In this way, the vibration can be measured at four positions and angles in sequence, and four groups of data can be obtained, making the vibration measurement more accurate; S4. After the test is completed, the motor (81) is turned off, and the telescopic rod (86) drives the square shaft (85) to leave the square hole (88).

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