Wind driven generator blade detection device

Abstract

The invention discloses a wind driven generator blade detection device, and relates to the technical field of wind driven generator blade detection, the wind driven generator blade detection device comprises a mounting rack, the upper surface of the mounting rack is fixedly connected with an electronic level meter, the other side of the upper surface of the mounting rack is fixedly connected with a control module, and the middle part of the mounting rack is provided with a detection probe; the lower end of the detection probe extends to the lower side of the mounting frame, a fixing mechanism is arranged on the upper side of the mounting frame, a heat dissipation mechanism is arranged on the lower side of the mounting frame, motors are fixedly connected to the two sides of the front side of the mounting frame, and balancing weights are fixedly connected to the output ends of the motors; by arranging the mounting rack, the detection probe, the suction cup and other structures, the detection probe is stably arranged on the surface of the fan blade, the device can continuously monitor the fan blade along with deflection of the fan blade, and the device has the advantages of being high in practicability and capable of reducing errors caused by inertia during detection.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine blade detection, and in particular to a wind turbine blade detection device. Background Art

[0002] A wind turbine is an electrical device that converts wind energy into mechanical work, which drives the rotor to rotate and finally outputs alternating current. A wind turbine generally consists of a wind rotor, a generator (including a device), a stabiliser (tail), a tower, a speed limit safety mechanism and an energy storage device. The working principle of a wind turbine is relatively simple. The wind rotor rotates under the action of wind force, which converts the kinetic energy of the wind into the mechanical energy of the wind rotor shaft. The generator rotates and generates electricity under the drive of the wind rotor shaft. The design of the blades in a wind turbine directly affects the conversion efficiency of wind energy and its annual power generation, and is an important part of wind energy utilization. Since the blades of wind turbines are large, they need to undergo strict quality inspections before leaving the factory for assembly; When conducting quality inspection on the blades of a wind turbine, the blades are generally shaken to induce deformation, and then stress inspection is performed on various parts of the blades. Existing inspection devices generally build a bracket on the surface of the blades, and then the bracket fixes the inspection device so that the inspection device can smoothly follow the blades for mobile inspection. However, after building a large bracket, due to the heavy weight and large volume of the bracket, it not only puts a burden on the site area, but also affects the load-bearing capacity when the blades shake, thereby affecting the stress change. If the bracket is not built, the inspection device will cause errors in the inspection data due to inertia when following the reciprocating movement of the blades. Therefore, it is necessary to design a wind turbine blade detection device that is highly practical and can reduce the error caused by inertia during detection. Summary of the invention

[0003] The object of the present invention is to provide a wind turbine blade detection device to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a wind turbine blade detection device, comprising a mounting frame, an electronic level is fixedly connected to the upper surface of the mounting frame, a control module is fixedly connected to the other side of the upper surface of the mounting frame, a detection probe is arranged in the middle of the mounting frame, the lower end of the detection probe extends to the lower side of the mounting frame, a fixing mechanism is arranged on the upper side of the mounting frame, a heat dissipation mechanism is arranged on the lower side of the mounting frame, both sides of the front side of the mounting frame are fixedly connected to motors, and a counterweight is fixedly connected to the output end of the motor; The electronic level is electrically connected to the control module, and the control module is electrically connected to the motor.

[0005] According to the above technical solution, the fixing mechanism includes a bracket, the lower side of the bracket is fixedly connected to the upper surface of the mounting frame, the upper inner wall of the bracket is rotatably connected to a threaded rod through a bearing, the outer wall of the threaded rod is threadedly connected to a threaded sleeve, both sides of the outer wall of the threaded sleeve are hinged with rocker arms, the lower end outer wall of the rocker arm is fixedly connected to an insertion rod, the outer wall of the insertion rod is sleeved with a rotating rod, the outer wall of the insertion rod contacts the inner wall of the rotating rod, and the lower end diameter of the insertion rod is larger than the middle diameter of the insertion rod, the outer wall of the rotating rod is rotatably connected to a fixed arm through a bearing, one end of the fixed arm is hinged to the upper surface of the mounting frame, the other end of the fixed arm is fixedly connected to an air cylinder, and the lower end of the air cylinder is fixedly connected to a suction cup.

[0006] According to the above technical solution, the lower surface of the suction cup and the lower surface of the detection probe are located at the same height, and the air cylinder is in a vertical state when the lower surface of the suction cup and the lower surface of the detection probe are located at the same height.

[0007] According to the above technical solution, the air cylinder is a hollow structure that runs through up and down, and a lower limit ring is fixedly connected to the lower part of the inner wall of the air cylinder, and an upper limit ring is fixedly connected to the upper part of the inner wall of the air cylinder, and an air pumping block is placed on the upper side of the lower limit ring. The air pumping block is a hollow structure that runs through up and down, and a one-way valve is provided in the middle part of the inner wall of the air pumping block, and the input side of the one-way valve is the lower side. An insert tube is provided on the side wall of the air cylinder, and the interior of the insert tube is connected to the interior of the air cylinder. A socket is provided on the upper side of the insert tube, and a plug plate is provided inside the socket. The outer wall of the plug plate is slidably connected to the inner wall of the socket, and a pull rope is fixedly connected to the upper surface of the plug plate, and the other end of the pull rope is fixedly connected to the lower surface of the plug rod, and a circular hole is provided in the middle part of the plug plate, and the insert tube is located at the lower side of the lower limit ring.

[0008] According to the above technical solution, the heat dissipation mechanism includes an air cavity box, the air cavity box is located in the middle of the mounting frame, the inner wall of the air cavity box is fixedly connected to the middle of the outer wall of the detection probe, a lifting hole is opened in the middle of the mounting frame, the middle outer wall of the air cavity box contacts the inner wall of the lifting hole, the diameter of the lower outer wall of the air cavity box is larger than the middle diameter of the air cavity box, and the lower inner diameter of the lifting hole is larger than the lower inner diameter of the air cavity box, and the lower outer wall of the air cavity box contacts the lower inner wall of the lifting hole. An electric telescopic rod is hinged on the upper surface of the lower side of the air cavity box, and the upper end of the electric telescopic rod is hinged to the upper side of the inner wall of the lifting hole. A fixing hole is provided on the air cavity box, and an exhaust pipe is fixedly connected to the inner wall of the fixing hole. The exhaust pipe is a tubular structure with an opening on the lower side, and the lower end of the exhaust pipe faces the lower side of the detection probe. The upper end of the exhaust pipe passes through the mounting frame and is fixedly connected to the upper outer wall of the air cavity box. An air inlet is provided on the side wall of the exhaust pipe between the air cavity box and the mounting frame.

[0009] According to the above technical solution, the electric telescopic rod is electrically connected to the control module, and the electronic level can transmit the state of the mounting frame to the control module, the control module can control the speed of the motor, and the control module can control the telescopic state of the electric telescopic rod.

[0010] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention provides a mounting frame, a detection probe, a suction cup and other structures so that the detection probe is stably assumed on the surface of the fan blade, so that the device can continuously monitor the fan blade as the fan blade deflects; By providing structures such as an electronic level, a control module, a motor, and a counterweight, the device can follow the deflection direction of the fan blade to reduce the influence on the suction cup, thereby increasing the stability of the device; By providing a movable vacuum block and other structures, the device can continuously extract the gas between the suction cup and the vacuum block during use, thereby avoiding the suction cup from loosening due to gas expansion during use; By providing an air cavity box and a detection probe that can move up and down, the device can quickly spray air to dissipate heat between the detection probe and the fan blade when the fan blade is deflected and restored to a horizontal state, thereby avoiding stress changes caused by local high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 It is a three-dimensional structural schematic diagram of the present invention; Figure 2 It is a schematic diagram of the fixing mechanism structure of the present invention; Figure 3 It is a schematic diagram of the split structure of the fixing mechanism of the present invention; Figure 4 It is a schematic diagram of the internal structure of the gas cylinder of the present invention; Figure 5 It is a schematic diagram of the structure of the mounting frame of the present invention; Figure 6 It is a schematic diagram of the internal structure of the air cavity box of the present invention; In the figure: 1. mounting bracket; 2. electronic level; 3. control module; 4. detection probe; 5. fixing mechanism; 6. heat dissipation mechanism; 7. motor; 8. counterweight; 501. bracket; 502. threaded rod; 503. threaded sleeve; 504. rocker arm; 505. plug rod; 506. rotating rod; 507. fixed arm; 508. air cylinder; 509. suction cup; 510. lower limit ring; 511. upper limit ring; 512. vacuum block; 513. plug tube; 514. plug plate; 515. pull rope; 601. air cavity box; 602. electric telescopic rod; 603. exhaust pipe; 604. air inlet. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] See also Figure 1-6 The present invention provides a technical solution: a wind turbine blade detection device, comprising a mounting frame 1, an electronic level 2 is fixedly connected to the upper surface of the mounting frame 1, a control module 3 is fixedly connected to the other side of the upper surface of the mounting frame 1, a detection probe 4 is arranged in the middle of the mounting frame 1, the lower end of the detection probe 4 extends to the lower side of the mounting frame 1, a fixing mechanism 5 is arranged on the upper side of the mounting frame 1, a heat dissipation mechanism 6 is arranged on the lower side of the mounting frame 1, both sides of the front side of the mounting frame 1 are fixedly connected to a motor 7, a counterweight block 8 is fixedly connected to the output end of the motor 7, the electronic level 2 and the control module 3 are electrically connected, and the control module 3 and the motor 7 are electrically connected; The fixing mechanism 5 includes a bracket 501, the lower side of the bracket 501 is fixedly connected to the upper surface of the mounting frame 1, the upper inner wall of the bracket 501 is rotatably connected to a threaded rod 502 through a bearing, the outer wall of the threaded rod 502 is threadedly connected to a threaded sleeve 503, both sides of the outer wall of the threaded sleeve 503 are hinged with rocker arms 504, the lower outer wall of the rocker arm 504 is fixedly connected to an insertion rod 505, the outer wall of the insertion rod 505 is sleeved with a rotating rod 506, the outer wall of the insertion rod 505 is in contact with the inner wall of the rotating rod 506, and the insertion rod 505 The diameter of the lower end is larger than the middle diameter of the insertion rod 505, the outer wall of the rotating rod 506 is rotatably connected to a fixed arm 507 through a bearing, one end of the fixed arm 507 is hinged to the upper surface of the mounting frame 1, the other end of the fixed arm 507 is fixedly connected to an air cylinder 508, the lower end of the air cylinder 508 is fixedly connected to a suction cup 509, the lower surface of the suction cup 509 is at the same height as the lower surface of the detection probe 4, and when the lower surface of the suction cup 509 is at the same height as the lower surface of the detection probe 4, the air cylinder 508 is in a vertical state; When in use, the detection probe 4 is connected to the power supply, and the lower side of the detection probe 4 is in contact with the surface of the fan blade, and then the threaded rod 502 is rotated. Since the outer wall of the threaded rod 502 is threadedly connected to the inner wall of the threaded sleeve 503, and the threaded sleeve 503 cannot rotate due to the limit of the rocker arm 504 and the fixed arm 507, the threaded sleeve 503 will move downward when the threaded rod 502 is rotated, so that the threaded sleeve 503 pushes the upper end of the rocker arm 504 downward, so that the rocker arm 504 pushes the fixed arm 507 downward, and the fixed arm 507 drives the air cylinder 5 08 moves downward, so that the suction cup 509 fits tightly on the surface of the fan blade, and then after the suction cup 509 is adsorbed and fits with the fan blade, a triangular support structure is formed through the air cylinder 508, the fixed arm 507, the rocker arm 504, the electronic level 2, and the threaded rod 502, so that the mounting frame 1 is stably assumed on the surface of the fan blade, and the lower side of the detection probe 4 fits with the surface of the fan blade, so that the fan blade can be stably assumed on the surface of the fan blade during the test process, so that the detection probe 4 continues to detect the quality of the fan blade, and the weight of the device is relatively low, and it will not cause excessive load impact on the fan blade; In the process of the device moving up and down following the shaking of the fan blades, the state of the mounting frame 1 is sensed by the electronic level 2, and the speed of the motor 7 is controlled by the control module 3, so that the motor 7 drives the counterweight 8 to rotate in the shaking direction of the fan blades. When the fan blades shake downward, the heavier end of the counterweight 8 deflects downward, thereby causing the device to generate a downward force, thereby making the device fit the surface of the fan blades. When the fan blades shake upward, the heavier end of the counterweight 8 rotates upward, so that the device will not be overly squeezed by the fan blades due to inertia, thereby reducing the pressure change between the lower end of the detection probe 4 and the surface of the fan blade, thereby reducing the detection error and reducing the influence of inertia on the adsorption of the lower side of the suction cup 509; The air cylinder 508 is a hollow structure that runs through from top to bottom, and a lower limit ring 510 is fixedly connected to the lower part of the inner wall of the air cylinder 508, and an upper limit ring 511 is fixedly connected to the upper part of the inner wall of the air cylinder 508. A vacuum block 512 is placed on the upper side of the lower limit ring 510. The vacuum block 512 is a hollow structure that runs through from top to bottom, and a one-way valve is arranged in the middle of the inner wall of the vacuum block 512, and the input side of the one-way valve is the lower side. The side wall of the air cylinder 508 is provided with an insert 51 3. The interior of the insert tube 513 is connected to the interior of the gas cylinder 508. A socket is provided on the upper side of the insert tube 513. A plug plate 514 is provided inside the socket. The outer wall of the plug plate 514 is slidably connected to the inner wall of the socket. A pull rope 515 is fixedly connected to the upper surface of the plug plate 514. The other end of the pull rope 515 is fixedly connected to the lower surface of the plug rod 505. A round hole is provided in the middle of the plug plate 514. The insert tube 513 is located at the lower side of the lower limit ring 510. When the fan blades are shaking up and down, the air pumping block 512 is only in contact with the inner wall of the air cylinder 508, so it is not fixed during the shaking process. When the fan blades deflect upward and then turn downward, the air pumping block 512 will be driven to move upward due to inertia. If the gas between the lower side of the air pumping block 512 and the lower side of the suction cup 509 expands or excess gas is retained, the air pumping block 512 will rise accordingly, so that the space between the suction cup 509 and the air pumping block 512 is increased, thereby causing the suction cup 509 to move upward. 9 is more closely attached to the surface of the fan blade. When the fan blade deflects downward and then turns upward, the air pumping block 512 will move downward due to inertia. Since the input side of the one-way valve in the middle is the lower side, when the air pumping block 512 moves downward, the gas on the lower side will be discharged into the upper side through the one-way valve, so that the excess gas between the air pumping block 512 and the suction cup 509 is discharged, so that the suction cup 509 always maintains a firm adsorption, avoiding the expansion of gas caused by heat generated when the fan blade deflects, thereby ensuring the stability of the device; The heat dissipation mechanism 6 includes an air cavity box 601, which is located in the middle of the mounting frame 1. The inner wall of the air cavity box 601 is fixedly connected to the middle of the outer wall of the detection probe 4. A lifting hole is opened in the middle of the mounting frame 1. The middle outer wall of the air cavity box 601 contacts the inner wall of the lifting hole. The diameter of the lower outer wall of the air cavity box 601 is larger than the middle diameter of the air cavity box 601, and the lower inner diameter of the lifting hole is larger than the lower inner diameter of the air cavity box 601. The lower outer wall of the air cavity box 601 contacts the lower inner wall of the lifting hole. The lower upper surface of the air cavity box 601 is hinged with an electric telescopic rod 602. The upper end of the electric telescopic rod 602 is hinged to the upper side of the inner wall of the lifting hole. The air cavity box 6 01 is provided with a fixing hole, the inner wall of the fixing hole is fixedly connected with an exhaust pipe 603, the exhaust pipe 603 is a tubular structure with an opening on the lower side, the lower end of the exhaust pipe 603 faces the lower side of the detection probe 4, the upper end of the exhaust pipe 603 passes through the mounting frame 1 and is fixedly connected with the upper outer wall of the air cavity box 601, the side wall of the exhaust pipe 603 is located between the air cavity box 601 and the mounting frame 1 and is provided with an air inlet 604, the electric telescopic rod 602 is electrically connected to the control module 3, and the electronic level 2 can transmit the state of the mounting frame 1 to the control module 3, the control module 3 can control the rotation speed of the motor 7, and the control module 3 can control the telescopic state of the electric telescopic rod 602; When the fan blades swing to a horizontal state, the fan blades are minimally affected by the outside world. At this time, after the electronic level 2 senses that the detection probe 4 is in a horizontal state, the control module 3 starts the electric telescopic rod 602 to perform a telescopic movement, so that when the electric telescopic rod 602 contracts, the air cavity box 601 is pulled upward, so that the air cavity box 601 drives the detection probe 4 to move upward, so that the lower side of the detection probe 4 is separated from the surface of the fan blade, thereby facilitating the separation of oxides and debris on the surface of the fan blade from between the detection probe 4 and the fan blade; In addition, during the upward movement of the air cavity box 601, the space between the air cavity box 601 and the mounting frame 1 is reduced, so that the gas between the air cavity box 601 and the mounting frame 1 is quickly discharged through the air inlet 604 and the exhaust pipe 603, so that the air flow quickly blows between the lower side of the detection probe 4 and the surface of the fan blade, thereby quickly dissipating the heat at the contact point between the detection probe 4 and the surface of the fan blade, avoiding the influence caused by the inability to quickly diffuse the heat at the contact point due to the long-term contact between the detection probe 4 and the fan blade; When removing the fan blade from the device, it is only necessary to rotate the threaded rod 502 in the opposite direction so that the threaded rod 502 can pull the insertion rod 505 through the rocker arm 504, which will cause the insertion rod 505 to move upward and pull the pull rope 515, so that a part of the insertion plate 514 can be moved out of the interior of the insertion tube 513, and then the lower side of the interior of the air cylinder 508 can be connected with the outside world through the insertion tube 513, and then the suction cup 509 will be loosened from the fan blade. When the rocker arm 504 continues to deflect upward, the lower end of the insertion rod 505 will be stuck on the rotating rod 506, so that the fixed arm 507 can be driven to deflect upward, thereby causing the device to detach from the surface of the fan blade.

[0014] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0015] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wind turbine blade detection device, comprising a mounting frame (1), characterized in that: The upper surface of the mounting frame (1) is fixedly connected to an electronic level (2), the other side of the upper surface of the mounting frame (1) is fixedly connected to a control module (3), a detection probe (4) is provided in the middle of the mounting frame (1), the lower end of the detection probe (4) extends to the lower side of the mounting frame (1), a fixing mechanism (5) is provided on the upper side of the mounting frame (1), a heat dissipation mechanism (6) is provided on the lower side of the mounting frame (1), both sides of the front side of the mounting frame (1) are fixedly connected to a motor (7), and a counterweight (8) is fixedly connected to the output end of the motor (7); The electronic level (2) and the control module (3) are electrically connected, and the control module (3) and the motor (7) are electrically connected.

2. A wind turbine blade detection device according to claim 1, characterized in that: The fixing mechanism (5) comprises a bracket (501), the lower side of the bracket (501) is fixedly connected to the upper surface of the mounting frame (1), the upper inner wall of the bracket (501) is rotatably connected to a threaded rod (502) via a bearing, the outer wall of the threaded rod (502) is threadedly connected to a threaded sleeve (503), the outer wall of the threaded sleeve (503) is hinged with a rocker arm (504) on both sides, the lower outer wall of the rocker arm (504) is fixedly connected to an insertion rod (505), and the outer wall of the insertion rod (505) is sleeved with a threaded sleeve (503). A rotating rod (506) is provided, the outer wall of the insertion rod (505) contacts the inner wall of the rotating rod (506), and the diameter of the lower end of the insertion rod (505) is larger than the middle diameter of the insertion rod (505), the outer wall of the rotating rod (506) is rotatably connected to a fixed arm (507) via a bearing, one end of the fixed arm (507) is hinged to the upper surface of the mounting frame (1), the other end of the fixed arm (507) is fixedly connected to an air cylinder (508), and the lower end of the air cylinder (508) is fixedly connected to a suction cup (509).

3. A wind turbine blade detection device according to claim 2, characterized in that: The lower surface of the suction cup (509) and the lower surface of the detection probe (4) are located at the same height, and when the lower surface of the suction cup (509) and the lower surface of the detection probe (4) are located at the same height, the gas cylinder (508) is in a vertical state.

4. A wind turbine blade detection device according to claim 3, characterized in that: The gas cylinder (508) is a hollow structure that runs through from top to bottom, and a lower limit ring (510) is fixedly connected to the lower portion of the inner wall of the gas cylinder (508), and an upper limit ring (511) is fixedly connected to the upper portion of the inner wall of the gas cylinder (508). An air pumping block (512) is placed on the upper side of the lower limit ring (510). The air pumping block (512) is a hollow structure that runs through from top to bottom, and a one-way valve is arranged in the middle of the inner wall of the air pumping block (512), the input side of the one-way valve is the lower side, and an insert (513) is arranged on the side wall of the gas cylinder (508). The interior of the insert tube (513) is connected to the interior of the gas cylinder (508), a socket is provided on the upper side of the insert tube (513), a plug plate (514) is provided inside the socket, the outer wall of the plug plate (514) is slidably connected to the inner wall of the socket, a pull rope (515) is fixedly connected to the upper surface of the plug plate (514), the other end of the pull rope (515) is fixedly connected to the lower surface of the plug rod (505), a round hole is provided in the middle of the plug plate (514), and the insert tube (513) is located at the lower side of the lower limit ring (510).

5. A wind turbine blade detection device according to claim 4, characterized in that: The heat dissipation mechanism (6) comprises an air cavity box (601), the air cavity box (601) being located in the middle of the mounting frame (1), the inner wall of the air cavity box (601) being fixedly connected to the middle of the outer wall of the detection probe (4), a lifting hole being provided in the middle of the mounting frame (1), the middle outer wall of the air cavity box (601) being in contact with the inner wall of the lifting hole, the diameter of the lower outer wall of the air cavity box (601) being larger than the middle diameter of the air cavity box (601), and the lower inner diameter of the lifting hole being larger than the lower inner diameter of the air cavity box (601), the lower outer wall of the air cavity box (601) being in contact with the lower inner wall of the lifting hole, and the lower side of the air cavity box (601) being An electric telescopic rod (602) is hingedly connected to the upper surface, the upper end of the electric telescopic rod (602) is hingedly connected to the upper side of the inner wall of the lifting hole, a fixing hole is provided on the air cavity box (601), an exhaust pipe (603) is fixedly connected to the inner wall of the fixing hole, the exhaust pipe (603) is a tubular structure with an opening at the lower side, the lower end of the exhaust pipe (603) faces the lower side of the detection probe (4), the upper end of the exhaust pipe (603) passes through the mounting frame (1) and is fixedly connected to the upper outer wall of the air cavity box (601), and an air inlet (604) is provided on the side wall of the exhaust pipe (603) between the air cavity box (601) and the mounting frame (1).

6. A wind turbine blade detection device according to claim 5, characterized in that: The electric telescopic rod (602) is electrically connected to the control module (3), and the electronic level (2) can transmit the state of the mounting frame (1) to the control module (3), the control module (3) can control the rotation speed of the motor (7), and the control module (3) can control the telescopic state of the electric telescopic rod (602).

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