Rail and heaped cone matching data detection method based on power fixed pulley wire falling device

Abstract

This invention discloses a method for detecting the matching data of a guide rail and a pile cone based on a dynamic fixed pulley plumb bob device, comprising the following steps: S1, installing the dynamic fixed pulley plumb bob device; S2, measuring the matching data of the plumb bob's pointing point and intersection point 5.1; S21, attaching the two adjacent surfaces on both sides of the guide rail angle steel in step S1; S22, using the handheld remote control from step S1 to control the motor to drive the plumb bob downwards via the speed and direction control component; S23, after the plumb bob is stable, checking the matching data of the plumb bob's pointing point and intersection point 5.1; S24, after the measurement data is completed, repairing the guide rail that exceeds the design tolerance range or correcting the pile cone position line based on the measurement data. This invention, by using a dynamic fixed pulley plumb bob device to detect the matching data of the guide rail and pile cone, can identify out-of-tolerance parts of the matching data and repair them in a timely manner, thus advancing the process and improving measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of container system multi-platform cargo hold guide rail and stacking cone matching degree detection technology, and more specifically, to a method for detecting guide rail and stacking cone matching data based on a dynamic fixed pulley plumb bob device. Background Technology

[0002] After the multi-platform cargo hold of a container ship is completed, the position lines of the stacking cones in the entire hold need to be drawn. After the position lines of the stacking cones are drawn, the data matching between the guide rails and the stacking cones needs to be checked. The test data is used as the container trial data to determine whether there are any deviations in the front-to-back and inside-outside distances after the container is lowered. The guide rails or stacking cones can be repaired as early as possible to meet the accuracy requirements during the actual container lifting and trial. Currently on container ships, during the container testing and acceptance process in the hold, shipowners require that the lateral clearance between the four corner fittings of the container and the guide rail angle steel of the first connecting plate at the bottom of the guide rail after the container is lowered should be 5-10mm, and the longitudinal clearance should be 10-18mm. In the past, when testing the data matching between the guide rail and the stacking cone in multi-platform cargo holds, scaffolding was erected at the bottom of the guide rail of each platform in the hold. Surveyors had to climb up the scaffolding with a simple plumb bob to test the data matching between the guide rail and the stacking cone. Two people were required to work together, and the personnel on the top and bottom had to measure the distance between the plumb bob and the guide rail surface and the stacking cone position line, and then perform a secondary calculation.

[0003] Currently, scaffolding is no longer erected inside container ships for assistance during construction. This makes it difficult to measure the guide rails of multi-platform cargo holds. In addition, even slight hand tremors during hand-held plumb line testing can affect the accuracy of distance measurement data and make it easier for data errors to occur during secondary data verification. Summary of the Invention

[0004] This invention aims to enable the detection of data consistency between the cabin guide rails and the platform pad cone without scaffolding, thereby ensuring and improving the accuracy of the measurement data.

[0005] To achieve the above objectives, the present invention provides a method for detecting the matching data between the guide rail and the pile cone based on a dynamic fixed pulley plumb bob device, comprising the following steps:

[0006] S1. Install a powered fixed pulley plumb line device;

[0007] The power fixed pulley plumb bob device is attached to the guide rail;

[0008] The structure of the power fixed pulley plumb bob device includes a rectangular shell, one corner of which is concave to form a chamfered surface;

[0009] The rectangular shell has several magnets spaced apart on two adjacent faces of its chamfered surface, and symmetrical wire holes are opened on two side plates of the rectangular shell perpendicular to the chamfered surface and the two adjacent faces.

[0010] The rectangular housing has a reel driven by a motor inside. The line on the reel passes around a limiting roller at the front end of the reel, exits the line hole, and connects to the plumb bob.

[0011] The rectangular housing also houses a motor speed and steering control component, as well as a battery connecting the motor speed and steering control component and the motor; the motor speed and steering control component is connected to a handheld remote control.

[0012] S2. Measure the matching data of the pointing point and the intersection point of the plumb line, and check whether the deviation value between the pointing point and the intersection point meets the tolerance requirements; wherein, the intersection point refers to the intersection point of the front and rear position lines and the left and right position lines of the pile cone on the pad;

[0013] S21. Let the two adjacent surfaces on both sides in step S1 adhere to the angle steel of the guide rail.

[0014] S22. Using the handheld remote control described in step S1, control the motor to drive the plumb line to fall through the speed and direction control component, so that there is a gap of 3mm to 5mm between the plumb line and the pad.

[0015] S23. After the plumb line is stabilized, check the matching data between the plumb line pointing point and the intersection point mentioned in step S2, that is, detect the deviation data corresponding to the plumb line pointing point and the intersection point, and determine the offset of the guide rail. If the spacing data between the guide rails meets the requirements, the position of the cone is corrected; otherwise, the actual position of the guide rail is adjusted.

[0016] Preferably, the magnet is a flat plate magnet.

[0017] Preferably, an antenna is provided on any one of the side plates of the rectangular housing.

[0018] Preferably, the side plate is provided with a tapered retaining sleeve on the wire outlet side of the wire hole.

[0019] Preferably, the conical retaining sleeve has a through hole in the middle for threading the wire, and a rotating fastening bolt is provided laterally on the outer side of the conical retaining sleeve. The screw-in end of the rotating fastening bolt extends into the through hole and engages with the inner wall of the through hole to clamp and fix the wire.

[0020] Preferably, the motor is a single-phase dual-speed motor, and the battery is a 12V storage battery.

[0021] Preferably, the control circuit principle of the power fixed pulley plumb bob device is as follows: the battery is connected to a DC12V / AC220V inverter through a wire, and the DC12V / AC220V inverter is connected to a first miniature circuit breaker and a second miniature circuit breaker through a wire. A power indicator light and a power indicator light fuse are connected in series between the first miniature circuit breaker and the second miniature circuit breaker.

[0022] Furthermore, a motor speed and direction adjustment circuit is provided between the first miniature circuit breaker QF1 and the second miniature circuit breaker QF2; the second miniature circuit breaker QF2 is connected to the motor speed and direction control circuit via a wire.

[0023] The motor speed and direction adjustment circuit includes a first contactor KM1 and a second contactor KM2. The contactor KM1 is connected to the motor and then connected to a first capacitor C1 and a third contactor KM3 in sequence via wires to form a closed circuit. The second contactor KM2 is connected to the motor 1.16 and then connected to a second capacitor C2 and a fourth contactor KM4 in sequence via wires to form a closed circuit.

[0024] The motor speed and direction control circuit includes a wireless transmission module and a control module. The control module includes a high-speed operation button S1, a low-speed operation button S2, and an up-down adjustment button SA.

[0025] The high-speed operation button S1 controls the opening and closing of the second contactor KM2, the third contactor KM3 and the fourth contactor KM4 through a signal connection, and is used to drive the motor 1.16 to run at high speed.

[0026] The low-speed operation button S2 controls the opening and closing of the first contactor KM1, the third contactor KM3, and the fourth contactor KM4 via a signal connection, and is used to drive the motor 1.16 to run at low speed.

[0027] The up / down adjustment button SA includes an upper limit switch SQ1 and a lower limit switch SQ2. The upper limit switch SQ1 is connected to the first intermediate relay KA1 and the second intermediate relay KA2 via a signal connection. The lower limit switch SQ2 is connected to the third contactor KM3 and the fourth contactor KM4 via a signal connection.

[0028] This invention uses a dynamic fixed pulley plumb bob device to detect the misalignment data between the guide rail and the stack cone, which can identify out-of-tolerance areas of the misalignment data and make timely repairs, thereby moving the process forward and improving measurement accuracy. Attached Figure Description

[0029] Figure 1This is a schematic diagram of the rectangular housing of the power fixed pulley plumb bob device described in this invention.

[0030] Figure 2 A schematic diagram of the rectangular housing with reinforcing plates of the power fixed pulley plumb bob device of the present invention.

[0031] Figure 3 This is a top view of the powered fixed pulley plumb bob device described in this invention.

[0032] Figure 4 This is a schematic diagram of the measurement process of the present invention.

[0033] Figure 5 This is a circuit diagram of the powered fixed pulley plumb bob device described in this invention.

[0034] Figure 6 This is a schematic diagram showing the arrangement of the pads on the inner bottom of the cabin.

[0035] Figure 7 This is a side view of the powered fixed pulley plumb bob device described in this invention.

[0036] The components include: 1. Powered fixed pulley and plumb bob device; 1.1. Rectangular housing; 1.2. Chamfered surface; 1.3. Magnet; 1.4. Adjacent surfaces; 1.5. Side plate; 1.6. Wire hole; 1.7. Antenna; 1.8. Reinforcing plate; 1.9. Wire wheel; 1.10. Wire; 1.11. Plumb bob; 1.12. Conical stabilizing sleeve; 1.121. Through hole; 1.122. Rotary fastening bolt; 1.13. Motor speed and direction control assembly; 1.14. Battery; 1.15. Handheld remote control; 1.16. Motor; 1.17. Limiting roller; 2. Guide rail; 3. Motor support base; 4. Battery slot; 5. Platform pad. 5.1. Intersection point; 5.2. Fore-and-aft position lines of the stacked cone; 5.3. Left-and-right position lines of the stacked cone; 6. Inner bottom of the compartment; 7. Centerline of the hull; QF1. First miniature circuit breaker; QF2. Second miniature circuit breaker; TB. DC12V / AC220V inverter; KM1~KM4. First contactor~Fourth contactor; S1. High-speed operation button; S2. Low-speed operation button; SA. Changeover switch; HL. Power indicator light; FU. Power indicator light fuse; KA1~KA2. First intermediate relay~Second intermediate relay; SQ1. Upper limit switch; SQ2. Lower limit switch. Detailed Implementation

[0037] Example:

[0038] A method for detecting the matching data between the guide rail and the pile cone based on a dynamic fixed pulley plumb bob device, such as... Figure 4 As shown, it includes the following steps:

[0039] S1. Install the power-driven fixed pulley plumb bob device 1;

[0040] The power fixed pulley plumb bob device 1 is attached to the guide rail 2;

[0041] like Figure 1 As shown, the structure of the power fixed pulley plumb bob device 1 includes a rectangular shell 1.1, and one corner of the rectangular shell 1.1 is concave to form a chamfered surface 1.2.

[0042] The rectangular shell 1.1 has several magnets 1.3 spaced apart on two adjacent faces 1.4 of its chamfered surface 1.2. The magnets 1.3 are flat plate magnets. Symmetrical wire holes 1.6 are formed on two side plates 1.5 perpendicular to the chamfered surface 1.2 and the two adjacent faces of the rectangular shell 1.1. Figure 2 As shown, a reinforcing plate 1.8 is also provided inside the rectangular housing 1.1. An antenna 1.7 is provided on any one of the side plates 1.5 of the rectangular housing 1.1 for use in conjunction with remote control. The reinforcing plate 1.8 is used to install and stabilize the reel 1.9.

[0043] like Figure 3 and Figure 7 As shown, the rectangular housing 1.1 has a reel 1.9 driven by a motor 1.16 inside. The line 1.10 on the reel 1.9 passes over a limiting roller 1.17 located at the front end of the reel 1.9, exits through the line hole 1.6, and connects to the plumb bob 1.11. The motor 1.16 is a single-phase dual-speed motor, and the battery 1.14 is a 12V storage battery. The battery 1.14 is preferably installed in the battery compartment 4.

[0044] The rectangular housing 1.1 also includes a motor speed and direction control assembly 1.13 and a battery 1.14 connecting the motor speed and direction control assembly 1.13 and the motor 1.16; the motor speed and direction control assembly 1.13 is connected to a handheld remote control 1.15. The motor 1.16 is mounted on a motor support 3. The side plate 1.5 has a tapered retaining sleeve 1.12 on the wire exit side of the wire hole 1.6. The tapered retaining sleeve 1.12 has a through hole 1.121 in the middle for the wire 1.10 to pass through, and a rotating fastening bolt 1.122 is provided laterally on the outer side of the tapered retaining sleeve 1.12. The screw-in end of the rotating fastening bolt 1.122 extends into the through hole 1.121 and clamps and fixes the wire 1.10 with the inner wall of the through hole 1.121.

[0045] S2. Measure the alignment data between the pointing point of the plumb bob 1.11 and the intersection point 5.1, and check whether the deviation between the pointing point and the intersection point 5.1 meets the tolerance requirements; where, if Figure 6As shown, the intersection point 5.1 refers to the intersection of the front and rear position lines 5.2 and the left and right position lines 5.3 of the stacked cone on the pad plate 5; the pad plate 5 is installed on the inner bottom 6 of the cabin, and the middle position of the inner bottom 6 of the cabin is the center line 7 of the hull.

[0046] S21. Let the two adjacent surfaces 1.4 on both sides in step S1 be attached to the angle steel of the guide rail 2;

[0047] S22. Using the handheld remote control 1.15 described in step S1, the motor 1.16 is controlled by the speed and direction control component 1.13 to drive the plumb bob 1.11 to fall, so that the plumb bob 1.11 has a gap of 3mm to 5mm with the pad 5;

[0048] S23. After the plumb bob 1.11 is stable, check the matching data between the pointing point of the plumb bob 1.11 and the intersection point 5.1 mentioned in step S2. That is, check the deviation data corresponding to the pointing point of the plumb bob and the intersection point 5.1, and determine the offset of the guide rail 2. If the spacing data between the guide rails 2 meets the requirements, the position of the cone is corrected; otherwise, the actual position of the guide rail 2 is adjusted.

[0049] like Figure 5 As shown, the control circuit principle of the power fixed pulley plumb bob device 1 is as follows: the battery 1.14 is connected to the DC12V / AC220V inverter TB through a wire, and the DC12V / AC220V inverter TB is connected to the first miniature circuit breaker QF1 and the second miniature circuit breaker QF2 through a wire. A power indicator light HL and a power indicator light fuse FU are connected in series between the first miniature circuit breaker QF1 and the second miniature circuit breaker QF2.

[0050] Furthermore, a motor speed and direction adjustment circuit is provided between the first miniature circuit breaker QF1 and the second miniature circuit breaker QF2; the second miniature circuit breaker QF2 is connected to the motor speed and direction control circuit via a wire.

[0051] The motor speed and direction adjustment circuit includes a first contactor KM1 and a second contactor KM2. The contactor KM1 is connected to the motor 1.16 and then connected to the first capacitor C1 and the third contactor KM3 in sequence through wires to form a closed circuit. The second contactor KM2 is connected to the motor 1.16 and then connected to the second capacitor C2 and the fourth contactor KM4 in sequence through wires to form a closed circuit.

[0052] The motor speed and direction control circuit includes a wireless transmission module and a control module. The control module includes a high-speed operation button S1, a low-speed operation button S2, and an up-down adjustment button SA.

[0053] The high-speed operation button S1 controls the opening and closing of the second contactor KM2, the third contactor KM3 and the fourth contactor KM4 through a signal connection, and is used to drive the motor 1.16 to run at high speed.

[0054] The low-speed operation button S2 controls the opening and closing of the first contactor KM1, the third contactor KM3, and the fourth contactor KM4 via a signal connection, and is used to drive the motor 1.16 to run at low speed.

[0055] The up / down adjustment button SA includes an upward limit switch SQ1 and a downward limit switch SQ2. The upward limit switch SQ1 is connected to the first intermediate relay KA1 and the second intermediate relay KA2 via a signal connection. The downward limit switch SQ2 is connected to the third contactor KM3 and the fourth contactor KM4 via a signal connection. When the up direction is selected on the handheld remote control 1.15, SQ1 closes, KA1 is energized, and KM3 closes. Simultaneously, pressing the high-speed button closes KM2, achieving the high-speed up function. When the down direction is selected on the remote control, SQ2 closes, KA2 is energized, and KM4 closes. Simultaneously, pressing the low-speed button closes KM1, achieving the low-speed down function. Similarly, both the low-speed up and high-speed down functions can be achieved simultaneously.

[0056] During operation, the power fixed pulley plumb bob device 1 of the present invention is placed on the guide rail 2, and the two adjacent surfaces 1.4 are respectively in close contact with the right angle surfaces of the angle steel of the guide rail 2. The stable assembly at the opening on the lower end face of the device is adjusted to a tight state. The handheld remote control 1.15 is used to control the falling and rising movements of the plumb bob 1.11. During the falling process, the plumb bob 1.11 is stopped remotely when it is about 5mm away from the pad 5. After the plumb bob 1.11 is in a stable state, the matching data of the measurement part is measured to determine whether the matching state of the data between the guide rail and the stacking cone meets the requirements of the test chamber.

[0057] The chamfered surface 1.2 of the rectangular shell 1.1 is an arc-shaped structure to avoid the weld at the joint of the guide rail angle steel. The distance from the wire hole 1.6 to the right-angled sides of the two rectangular shells 1.1 is equal, both being 100mm. The upper end of the wire hole 1.6 is equipped with a limit roller 1.17 and a reinforcing plate 1.8 to ensure the stability of the plumb bob 1.10; the lower end of the wire hole 1.6 is equipped with a conical stabilizing sleeve 1.12 to ensure that the downward movement of the plumb bob 1.11 remains relatively stable and will not cause free fall due to the weight of the plumb bob 1.11. The conical stabilizing sleeve 1.12 is a solid structure with a through hole 1.121 in the middle, and a rotating fastening bolt 1.122 is provided on its side to ensure that it can still secure the plumb bob after long-term wear of the internal fine holes. The rolling spool inside the device is controlled by a remote control to adjust the up and down direction of the plumb bob 1.11, and the operator is located at the lower end of the device to perform the final stable point measurement of the plumb bob.

[0058] The device has an R50 chamfer at the right-angled corner to prevent it from touching the welded position of the guide rail angle steel; a Φ2mm opening is made on the lower end face of the device, and the distance between the opening and the right-angled side plate of the device is 100mm to ensure the consistency of subsequent data measurement; a right-angled spool stabilizing reinforcing plate 1.9 is installed inside the device, and a limit roller is installed on the reinforcing plate 1.9; the structure contains a motor, spool, and motor speed and direction control components, and a support base is set at the motor location, and a battery slot 4 for placing battery 1.14 is measured.

[0059] This invention utilizes the magnetic attraction of magnets to steel guide rails. Four magnets are installed on the two right-angled sides of the device, keeping them close to the angle steel surface of the guide rail, ensuring the relative positional stability of the device and the guide rail surface, and providing stable working conditions for the electric plumb bob. It also utilizes the rotation principle of an electric rolling bob, with a motor-driven reel inside the device and a remote control spare part, allowing the plumb bob's descent and ascent to be controlled remotely during operation. A stabilization device is installed at the lower end of the plumb bob to ensure stability during its descent, enabling the electric rolling bob inside the device to overcome mechanical principles and maintain mechanical balance. This doubles the detection efficiency. Measurements of the guide rail and cone data matching can be performed without personnel climbing bulkheads or scaffolding; the measurement process can be completed remotely by one person. A single-phase dual-speed motor is selected. Since this device is a low-power load, a 12V battery pack is used for power supply, which is converted to 220V AC by an inverter. When the remote control is set to "Up", SQ1 closes, KA1 is energized, and KM3 closes. Simultaneously, pressing the high-speed button closes KM2, enabling the high-speed up function. When the remote control is set to "Down", SQ2 closes, KA2 is energized, and KM4 closes. Simultaneously, pressing the low-speed button closes KM1, enabling the low-speed down function. Similarly, both low-speed up and high-speed down functions can be achieved simultaneously.

[0060] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for detecting the matching data of a guide rail and a pile cone based on a power trolley block device, characterized in that, Includes the following steps: S1. Install the power fixed pulley plumb bob device (1); The power fixed pulley plumb bob device (1) is attached to the guide rail (2); The structure of the power fixed pulley plumb bob device (1) includes a rectangular shell (1.1), one corner of which is concave to form a chamfered surface (1.2); The rectangular shell (1.1) has several magnets (1.3) spaced apart on two adjacent faces (1.4) of its chamfered surface (1.2). The rectangular shell (1.1) has symmetrical wire holes (1.6) on two side plates (1.5) perpendicular to the chamfered surface (1.2) and the two adjacent faces. The rectangular housing (1.1) is equipped with a reel (1.9) driven by a motor (1.16). The line (1.10) on the reel (1.9) passes around the limiting roller (1.17) at the front end of the reel (1.9), exits the line hole (1.6), and connects to the plumb bob (1.11). The rectangular housing (1.1) also includes a motor speed and steering control assembly (1.13) and a battery (1.14) connecting the motor speed and steering control assembly (1.13) and the motor (1.16); the motor speed and steering control assembly (1.13) is connected to a handheld remote control (1.15); S2. Measure the matching data of the pointing point and the intersection point (5.1) of the plumb line (1.11), and check whether the deviation value between the pointing point and the intersection point (5.1) meets the tolerance requirements; wherein, the intersection point (5.1) refers to the intersection of the front and rear position lines (5.2) and the left and right position lines (5.3) of the pile cone on the pad (5); S21. Let the two adjacent surfaces (1.4) on both sides in step S1 adhere to the angle steel of the guide rail (2); S22. Using the handheld remote control (1.15) described in step S1, control the motor (1.16) through the speed steering control component (1.13) to drive the plumb bob (1.11) to fall, so that the plumb bob (1.11) and the pad (5) have a gap of 3mm to 5mm. S23. After the plumb bob (1.11) is stabilized, check the matching data between the pointing point of the plumb bob (1.11) and the intersection point (5.1) mentioned in step S2. That is, check the deviation data corresponding to the pointing point of the plumb bob and the intersection point (5.1) to determine the offset of the guide rail (2). If the spacing data between the guide rails (2) meets the requirements, the position of the pile cone is corrected; otherwise, the actual position of the guide rail (2) is adjusted.

2. The method of claim 1, wherein the matching data of the guide rail and the pile cone based on the power trolley block device is detected. The magnet (1.3) is a flat magnet.

3. The method of claim 1, wherein the matching data of the guide rail and the pile cone based on the power trolley block device is characterized by, An antenna (1.7) is provided on any one of the side plates (1.5) of the rectangular housing (1.1).

4. The method for detecting the matching data of the guide rail and the pile cone based on the dynamic fixed pulley plumb bob device according to claim 1, characterized in that, The side plate (1.5) is provided with a tapered retaining sleeve (1.12) on the wire exit side of the wire hole (1.6).

5. The method for detecting the matching data of the guide rail and the pile cone based on the dynamic fixed pulley plumb bob device according to claim 4, characterized in that, The conical stabilizing sleeve (1.12) has a through hole (1.121) in the middle for threading the wire (1.10). The outer side of the conical stabilizing sleeve (1.12) is provided with a rotating fastening bolt (1.122). The screw-in end of the rotating fastening bolt (1.122) extends into the through hole (1.121) and cooperates with the inner wall of the through hole (1.121) to clamp and fix the wire (1.10).

6. The method for detecting the matching data of the guide rail and the pile cone based on the dynamic fixed pulley plumb bob device according to claim 1, characterized in that, The motor (1.16) is a single-phase dual-speed motor, and the battery (1.14) is a 12V storage battery.

7. The method for detecting the matching data of the guide rail and the pile cone based on the dynamic fixed pulley plumb bob device according to claim 1, characterized in that, The control circuit principle of the power fixed pulley plumb bob device (1) is as follows: the battery (1.14) is connected to the DC12V / AC220V inverter (TB) through a wire, and the DC12V / AC220V inverter (TB) is connected to the first miniature circuit breaker (QF1) and the second miniature circuit breaker (QF2) through a wire. A power indicator light (HL) and a power indicator light fuse (FU) are connected in series between the first miniature circuit breaker (QF1) and the second miniature circuit breaker (QF2). Furthermore, a motor speed and direction adjustment circuit is provided between the first miniature circuit breaker (QF1) and the second miniature circuit breaker (QF2); the second miniature circuit breaker (QF2) is connected to the motor speed and direction control circuit via a wire. The motor speed and direction adjustment circuit includes a first contactor (KM1) and a second contactor (KM2). The contactor (KM1) is connected to the motor (1.16) and then connected to a first capacitor (C1) and a third contactor (KM3) in sequence via wires to form a closed loop. The second contactor (KM2) is connected to the motor (1.16) and then connected to a second capacitor (C2) and a fourth contactor (KM4) in sequence via wires to form a closed loop. The motor speed and direction control circuit includes a wireless transmission module and a control module. The control module includes a high-speed operation button (S1), a low-speed operation button (S2), and an up-down adjustment button (SA). The high-speed operation button (S1) controls the opening and closing of the second contactor (KM2), the third contactor (KM3), and the fourth contactor (KM4) through a signal connection, thereby driving the motor (1.16) to run at high speed. The low-speed operation button (S2) controls the opening and closing of the first contactor (KM1), the third contactor (KM3), and the fourth contactor (KM4) via a signal connection, thereby driving the motor (1.16) to run at low speed. The up / down adjustment button (SA) includes an upper limit switch (SQ1) and a lower limit switch (SQ2). The upper limit switch (SQ1) is connected to the first intermediate relay (KA1) and the second intermediate relay (KA2) via a signal connection. The lower limit switch (SQ2) is connected to the third contactor (KM3) and the fourth contactor (KM4) via a signal connection.

Images