Control device for unloading machine, unloading machine, and control method for unloading machine

Abstract

To provide a control device or the like of an unloading machine capable of properly adjusting a load of a screw conveyor even when unloading a cargo with a small angle of repose.SOLUTION: A control device 300 for an unloading machine including a rotation take-in unit 11 configured to take in cargo along a circumferential direction thereof while rotating about a take-in rotation axis, and a screw conveyor 90 configured to convey the cargo taken in by the rotation take-in unit 11 along an axial direction thereof while rotating about a screw rotation axis includes a screw conveyor load detection unit 310 configured to detect a load on the screw conveyor 90, and a take-in rotation speed adjustment unit 400 configured to adjust a rotation speed of the rotation take-in unit 11 according to the load detected by the screw conveyor load detection unit 310.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a control device for a lifting machine. [Background technology]

[0002] Ship unloaders, which unload bulk cargo or bulk materials such as coal and iron ore from a ship's hold onto land, are known as unloading machines. Patent Document 1 discloses an unloader equipped with a vertical screw conveyor as a ship unloader. A vertical screw conveyor is also called a vertical screw conveyor, and is also referred to as a VSC (Vertical Screw Conveyor) in this disclosure. While the application of this disclosure is not limited to VSCs, this specification describes VSCs as a representative example of the unloading machine according to this disclosure. The VSC may refer to a portion of the ship unloader, including the rotary intake section and screw conveyor described below, or may refer to the entire ship unloader.

[0003] Patent Document 1 discloses that the rotational speed of the motor that drives the entire unloader is adjusted according to the power supplied to the motor that drives the screw conveyor. The power supplied to the motor that drives the screw conveyor represents the load on the screw conveyor. Therefore, for example, if the supplied power is large, the unloader's traveling speed is reduced to reduce the amount of bulk material taken in from the intake port at the bottom of the screw conveyor so that the screw conveyor does not become overloaded. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 3-26614 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, growing environmental awareness has led to increased attention being paid to biofuels (sometimes called biomass fuels), which have a lower environmental impact than conventional fuels such as coal. When such biofuels are unloaded by a VSC, their tendency to collapse (in other words, their small angle of repose) can be a problem. Conventional coals generally have a large angle of repose, so the "cliffs" formed by "excavation" by a VSC are less likely to collapse. On the other hand, the "cliffs" of biofuels, which have a small angle of repose, easily collapse. In such cases, even if the unloader's traveling speed is reduced to prevent overloading of the screw conveyor as in Patent Document 1, the collapse of the "cliffs" could result in a large amount of biofuel flowing into the intake, potentially causing the screw conveyor to become overloaded.

[0006] The present disclosure has been made in consideration of these circumstances, and aims to provide a control device for a lifting machine that can appropriately adjust the load on a screw conveyor even when unloading cargo with a small angle of repose. [Means for solving the problem]

[0007] In order to solve the above problems, a control device for a hoisting machine in one embodiment of the present disclosure is a control device for a hoisting machine that includes a rotating intake section that rotates around an intake rotation axis and takes in cargo along its circumferential direction, and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotating intake section along its axial direction, and that includes a screw conveyor load detection section that detects the load on the screw conveyor, and an intake rotation speed adjustment section that adjusts the rotation speed of the rotating intake section in accordance with the load detected by the screw conveyor load detection section.

[0008] In this embodiment, the rotation speed of the rotary intake section is adjusted according to the detected load on the screw conveyor. The rotation speed of the rotary intake section determines the maximum amount of cargo that can be delivered to the downstream screw conveyor, so adjusting this speed directly adjusts the load on the screw conveyor. Note that while this disclosure is suitable for unloading cargo with a small angle of repose (i.e., cargo that is easily crumbled) (e.g., biofuel, grain), it is also applicable to unloading cargo with a large angle of repose (i.e., cargo that is not easily crumbled) (e.g., coal, iron ore).

[0009] Another aspect of the present disclosure is a lifting machine including a rotary intake section that rotates around an intake rotation axis and takes in cargo along the circumferential direction of the intake rotation axis, and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotary intake section along the axial direction of the screw rotation axis, the lifting machine also including a screw conveyor load detection section that detects a load on the screw conveyor, and an intake rotation speed adjustment section that adjusts the rotation speed of the rotary intake section in accordance with the load detected by the screw conveyor load detection section.

[0010] Yet another aspect of the present disclosure is a control method for a lifting machine including a rotary intake section that rotates around an intake rotation axis and takes in cargo along the circumferential direction of the intake section, and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotary intake section along the axial direction of the screw rotation axis, the control method comprising detecting a load on the screw conveyor and adjusting the rotation speed of the rotary intake section in response to the detected load.

[0011] Any combination of the above components, or any conversion of these expressions into methods, devices, systems, recording media, computer programs, etc., are also encompassed within the present disclosure. [Effects of the Invention]

[0012] According to the present disclosure, the load on the screw conveyor can be appropriately adjusted even when unloading cargo with a small angle of repose. [Brief explanation of the drawings]

[0013] [Figure 1] 1 shows the overall configuration of the lifting machine. [Figure 2] 2 is a schematic diagram of the rotary intake section as viewed from below in FIG. 1; [Figure 3] FIG. 2 is a schematic functional block diagram of a control device of a VSC. [Figure 4] This section shows a schematic and simple way of thinking about how to calculate the load on a screw conveyor from the current of an induction motor. [Figure 5] This section shows a schematic and simple way of thinking about how to calculate the load on a screw conveyor from the current of an induction motor. [Figure 6] An example of conversion from load / torque to rotational speed in the conversion unit is shown. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments for carrying out the present disclosure (hereinafter also referred to as embodiments) will be described in detail with reference to the drawings. In the description and / or drawings, identical or equivalent components, members, processes, etc. are designated by the same reference numerals, and redundant description will be omitted. The scale and shape of each part shown in the drawings are set for convenience to simplify the description and should not be construed as limiting unless otherwise specified. The embodiments are merely examples and do not limit the scope of the present disclosure in any way. Not all features and combinations thereof presented in the embodiments are necessarily essential to the present disclosure. For convenience, the embodiments are presented broken down into components for each function and / or functional group that realizes the features. However, one component in an embodiment may actually be realized by a combination of multiple separate components, or multiple components in an embodiment may actually be realized by a single integrated component. Furthermore, although multiple embodiments and variants may be disclosed in parallel, any components of each embodiment and / or each variant may be combined in any manner as long as they do not interfere with each other's functions.

[0015] 1 shows the overall configuration of a lifting machine 1 according to an embodiment of the present disclosure. The lifting machine 1 is a ship unloader that unloads bulk goods M loaded on a ship 200 or as cargo onto land. The lifting machine 1 according to this embodiment is equipped with a VSC, and therefore will also be referred to as a VSC1 below. The VSC1 continuously carries out onto land bulk goods M stored in a hold 201 of a ship 200 that has come alongside a quay 101 of a wharf 102 of a port or the like.

[0016] Typical examples of bulk material M include coal, coke, ore, etc. In this embodiment, bulk material M with a small angle of repose (i.e., easily crumbled), such as biofuel or grain, is described as an example. In particular, the bulk material M in this embodiment is wood pellets (or white pellets or wood pellets, which are a type of wood pellets), which are a typical biofuel. Note that the biofuel may also be other wood biofuels such as wood chips or sawdust. Furthermore, the bulk material M is not limited to biofuel, and may also be grains such as wheat or soybeans.

[0017] The VSC1 may be operated by an operator in a main operation room (not shown) provided on the main body or the like of the VSC1. Alternatively, the VSC1 may be operated remotely by an operator located anywhere inside or outside the VSC1 via a remote controller or the like. The VSC1 may also be automatically operated according to a predetermined program or algorithm, or by artificial intelligence with machine learning capabilities.

[0018] The wharf 102 where the ship 200 docks constitutes land where bulk cargo M is unloaded, and is made of high-strength materials such as reinforced concrete. The wharf 102 is provided with a pair of parallel rails 3 as tracks that run along the longitudinal direction (perpendicular to the plane of the paper in FIG. 1 ) of the ship 200 docked at the quay 101 and anchored there. The rails 3 form a track along which the traveling section 2, which serves as the mobile section of the VSC 1, can move or run. The rails 3 enable the VSC 1 to move relative to the anchored ship 200. The installation direction of the rails 3 preferably coincides with the longitudinal direction of the anchored ship 200 or the quay 101, but may be any other direction. The rails 3 may also include curved or bent sections. When unloading cargo from the ship 200, the VSC 1 moves on the rails 3 and approaches a hatch 21, which serves as an upper opening of the hold 201 from which cargo is to be unloaded. Thereafter, the traveling section 2, the swivel frame 5, the lifting section 9, etc. are driven, and the bulk goods M are lifted from the hold 201. Note that, although the example in which the traveling section 2 moves along the rails 3 has been shown in this embodiment, the rails 3 may be omitted by configuring the traveling section 2 with rubber tires or the like that can move on the ground.

[0019] At the wharf 102, a belt conveyor 45 is provided between the pair of rails 3 as a conveyor for transporting the unloaded bulk goods M in a certain direction. The installation direction of the belt conveyor 45, i.e., the transport direction, preferably coincides with the installation direction of the rails 3, but may be any other direction. The belt conveyor 45 may also include curved or bent portions. The belt conveyor 45 needs to be provided between the pair of rails 3 at the location where the bulk goods M unloaded from the VSC 1 are received, but may be provided outside the pair of rails 3 at other locations.

[0020] The VSC 1 comprises a traveling section 2 as a moving section that can move relative to the ship 200, a swivel frame 5 as a swivel section that can swivel relative to the traveling section 2, and a lifting section 9 as a cargo handling or lifting device that is provided at the tip of the swivel frame 5 and transports bulk cargo M. The swivel frame 5 is supported on the traveling section 2 so as to be rotatable about a rotation axis in the vertical direction (the up and down direction in FIG. 1). The swivel frame 5 is provided with a boom 7 that extends laterally and intersects with the rotation axis, and a transport section or screw conveyor 90 that constitutes the main part of the lifting section 9 is supported at the tip of the boom 7.

[0021] The lifting unit 9 is raised and lowered by a hoisting mechanism consisting of the revolving frame 5 and the boom 7, and a hydraulic cylinder (not shown) installed between the boom 7 and the lifting unit 9 keeps the lifting unit 9 in a vertical position regardless of the boom 7's hoisting angle (the angle of rotation around the hoisting axis perpendicular to the plane of the page in FIG. 1). A counterweight 13 is installed at the rear end of the revolving frame 5 opposite the tip of the boom 7. The counterweight 13 is connected to the tip of the boom 7 via a balancing lever 12. The action of this counterweight 13 keeps the lifting unit 9 substantially unloaded, achieving a stable load balance. The main components of the revolving unit, such as the revolving frame 5, boom 7, balancing lever 12, and counterweight 13, are hereinafter collectively referred to as the main body.

[0022] A cylinder (not shown) is provided to adjust the hoisting angle of the boom 7. When the cylinder is at its standard length, the hoisting angle is 0 degrees, i.e., the boom 7 is parallel or horizontal to the ground (left and right in Figure 1). When the cylinder is extended beyond the standard length, the tip of the boom 7 rises, resulting in a positive hoisting angle. When the cylinder is retracted beyond the standard length, the tip of the boom 7 descends, resulting in a negative hoisting angle.

[0023] A main control room (not shown) for operating the VSC 1 may be provided in the main body of the VSC 1 or the slewing unit. The operator in the main control room can safely operate the VSC 1 while visually checking the unloading unit 9. The operator in the main control room may also operate the VSC 1 while visually checking on a monitor an image or video of the inside of the hold 201 captured by a camera or other imaging device. Parameters related to the position, attitude, operation, etc. of the VSC 1, such as the position of the traveling unit 2, the rotation angle of the revolving frame 5, and the hoisting angle of the boom 7 (hereinafter collectively referred to as the VSC state), are controlled in accordance with the operation of the VSC 1 through the main control room or the like. The unloading operation of the unloading unit 9 to carry out the bulk load M can also be controlled through the main control room or the like. The VSC 1 may be configured so that an operator outside the main control room can operate it from outside the VSC 1 via a wireless remote control.

[0024] The unloading section 9 includes a rotary intake section 11 that rotates to take in bulk goods M in the hold 201, and a screw conveyor 90 that transports the bulk goods M taken in by the rotary intake section 11 upward out of the hold 201 by the rotation of a screw (not shown). The rotary intake section 11 is provided below the unloading section 9 or the screw conveyor 90. The rotary intake section 11 is also called an excavation blade, etc., because it takes in the bulk goods M while excavating it as it rotates.

[0025] FIG. 2 is a schematic diagram of the rotary intake section 11 as viewed from below in FIG. 1. As shown in this figure, the rotary intake section 11 has a substantially circular cross section in plan view or bottom view, and includes a substantially cylindrical main body 111 extending in the up-down direction (typically the vertical direction) in FIG. 1. One or more intake ports 112 for taking in bulk goods M into the main body 111 are provided on the outer periphery of the substantially circular main body 111 in FIG. 2. When multiple intake ports 112 are provided, they are preferably provided at substantially equal intervals along the circumferential direction of the main body 111. In the example of FIG. 2, where three intake ports 112 are provided at equal intervals along the circumferential direction of the main body 111, the central angle formed between adjacent two intake ports 112 and the center O of the main body 111 is 120 degrees.

[0026] The rotary intake section 11 is driven to rotate in a counterclockwise direction (hereinafter also referred to as the rotation direction) around an intake rotation axis passing through the center O in FIG. 2. Each intake opening 112 has an extension plate 113 extending in the rotation direction along a tangent direction of the approximately circular cross section of the main body 111. The tip of the extension plate 113 forms a bent portion 114 that is slightly bent toward the main body 111. When such an extension plate 113 is driven to rotate integrally with the main body 111, it is mainly the bent portion 114 that effectively excavates the surrounding bulk material M (not shown) and takes it into the main body 111 through the intake opening 112, which is an opening between the extension plate 113 and the outer periphery of the main body 111. The bulk material M taken into the main body 111 from each intake opening 112 is transported upward in FIG. 1 (a direction perpendicular to the plane of the paper in FIG. 2, hereinafter also referred to as the axial direction) by a screw conveyor 90, which is schematically shown in the center of FIG. 2.

[0027] The screw conveyor 90 includes a screw (not shown) that extends from the rotary intake section 11 at the lower end in Fig. 1 to the boom 7 at the upper end. The screw is driven to rotate around the screw rotation axis, which is also its central axis, and transports the bulk goods M taken in by the rotary intake section 11 along the axial direction to the boom 7.

[0028] As described above, the VSC1 as a lifting machine according to this embodiment comprises a rotary intake section 11 that rotates around an intake rotation axis (an axis perpendicular to the plane of the drawing that passes through the center O) as shown in Fig. 2, and takes in bulk goods M along its circumferential direction, and a screw conveyor 90 that rotates around a screw rotation axis in the extension direction of the screw conveyor 90 in Fig. 1, and transports the bulk goods M taken in by the rotary intake section 11 along its axial direction. In the preferred example shown in the figure, the intake rotation axis, which is the rotation axis of the rotary intake section 11, and the screw rotation axis, which is the rotation axis and extension axis of the screw conveyor 90, are substantially parallel or on a straight line, but the intake rotation axis and the screw rotation axis may intersect at any angle.

[0029] 1, bulk goods M taken in by rotary take-in section 11 and transported to boom 7 by screw conveyor 90 are then transported to the vicinity of the rotation axis of rotating frame 5 by a boom conveyor (not shown) within boom 7. These bulk goods M descend along the rotation axis through chute 16 and are temporarily stored in hopper 43. When there is a belt conveyor 45 or a container (not shown) below hopper 43 that can receive bulk goods M, the gate of hopper 43 is opened and the bulk goods M temporarily stored in hopper 43 are transferred to the belt conveyor 45 or the container.

[0030] FIG. 3 is a schematic functional block diagram of a control device 300 of a VSC 1 according to this embodiment. The control device 300 includes a screw conveyor load detection unit 310, a division unit 320, a conversion unit 330, a multiplication unit 340, and a rotational speed command unit 350. Some of these functional blocks may be omitted as long as the control device 300 can achieve at least some of the functions and / or effects described below. These functional blocks may be implemented by the cooperation of hardware resources, such as a central processing unit (CPU), memory, input devices, output devices, and peripheral devices connected to the computer, and software executed using these hardware resources. Regardless of the type or location of the computer, each of the above functional blocks may be implemented by the hardware resources of a single computer or by combining hardware resources distributed across multiple computers.

[0031] The screw conveyor load detection unit 310 detects the load on the screw conveyor 90 (or its screw, not shown). The screw conveyor load detection unit 310 may detect the load directly from the torque or rotation speed of the screw conveyor 90, or may detect the load indirectly from the motor 60 that rotates and drives the screw conveyor 90, or may detect the load indirectly from the inverter 61 that serves as a power supply unit that supplies power to the motor 60. The load on the motor 60 detected by the screw conveyor load detection unit 310 may be interpreted as the torque generated by the motor 60.

[0032] In this embodiment, the motor 60 is an AC motor that drives the screws in the screw conveyor 90 to rotate based on AC power such as three-phase AC, and the inverter 61 supplies the AC power to the motor 60. However, the motor 60 may be a DC motor that drives the screws in the screw conveyor 90 to rotate based on DC power, in which case a DC power supply unit capable of supplying the DC power is provided instead of the inverter 61.

[0033] The screw conveyor load detection unit 310 preferably detects the load of the screw conveyor 90 based on the current of the motor 60 that rotates and drives the screw conveyor 90. The current of the motor 60 may be obtained directly from the motor 60, or may be obtained indirectly from the inverter 61 that supplies the current to the motor 60.

[0034] 4 and 5 show a schematic and simplified approach to determining the load of the screw conveyor 90 from the current of the motor 60, when the motor 60 is an induction motor. FIG. 4 shows a simplified equivalent circuit of the motor 60, which is an induction motor. In this diagram, V is the terminal voltage, g0 is the excitation conductance, r2' is the secondary winding resistance converted to the primary side, s is the slip, I0 is the excitation current, I1 is the motor current, and I2 is the load current. For simplicity, the primary winding resistance and winding leakage reactance are omitted from the equivalent circuit shown in FIG. 4. As shown schematically in FIG. 5, in a two-dimensional plane, the excitation current I0 and the load current I2 are orthogonal vectors, and their sum is the motor current I1. Therefore, I0 2 +I2 2 =I1 2 , is generally true.

[0035] Here, the motor current I1 can be acquired or measured by the screw conveyor load detection unit 310 from the motor 60 and / or inverter 61. Also, the excitation current I0 is generally given as basic data in the specifications of the motor 60. Therefore, I2 = √(I1 2 -I0 2) to determine the load current I2. The load on the motor 60 and / or the screw conveyor 90 is approximately equal to the load current I2 multiplied by the resistance r2' and divided by the slippage s. Both the resistance r2' and the slippage s are known as so-called motor constants, so the load on the motor 60 and / or the screw conveyor 90 can be determined from the load current I2 determined according to FIG. 5.

[0036] If a rotary encoder or the like is provided to measure the number of rotations or rotation speed of the motor 60, the screw conveyor load detection unit 310 may detect the load of the screw conveyor 90 based on the measured number of rotations. Specifically, the relational expression P=N×T holds between the power P supplied by the inverter 61 to the motor 60 (which can be obtained from the inverter 61 and / or the motor 60), the number of rotations N of the motor 60 (which can be obtained from a rotary encoder or the like), and the torque T of the motor 60, so the torque T as the load on the motor 60 can be found as T=P / N.

[0037] 3, a division unit 320 divides the load of the screw conveyor 90 or the torque of the motor 60 detected by the screw conveyor load detection unit 310 by a predetermined reference value 321. This reference value 321 is used to convert (or normalize) the load / torque detected by the screw conveyor load detection unit 310 into a dimensionless quantity for the convenience of converting the load / torque into the rotational speed of the rotation take-in unit 11 in a conversion unit 330 at a subsequent stage, which will be described later.

[0038] The reference value 321 can be set arbitrarily, but for example, the load / torque value when the motor 60 is operating at its rated capacity is used. In this case, the output of the divider 320 when the motor 60 is actually operating at its rated capacity is "1.00." When the motor 60 is operating at or below its rated capacity, the output of the divider 320 is "1.00" or less, and when the motor 60 is operating at or above its rated capacity, the output of the divider 320 is "1.00" or more.

[0039] The conversion unit 330 converts the load of the screw conveyor 90 or the torque of the motor 60, which is detected by the screw conveyor load detection unit 310 and normalized through the division unit 320, into the desired rotational speed of the rotation intake unit 11 (strictly speaking, the underlying dimensionless quantity).

[0040] 6 shows an example of the conversion from load / torque to rotational speed in the conversion unit 330. In this figure, the horizontal axis represents the normalized load / torque from the division unit 320 as the input to the conversion unit 330, and the vertical axis represents the desired rotational speed of the rotation capture unit 11 as the output of the conversion unit 330.

[0041] The conversion unit 330 converts the load / torque input from the division unit 320 into a value between the minimum value "0" and the upper limit value T max (greater than the load / torque during rated operation (e.g., "1.00")), the rotation speed of the rotation intake portion 11 is adjusted accordingly.

[0042] The load / torque input from the division unit 320 is adjusted to the adjustment-free threshold T th (less than the load / torque during rated operation (e.g., "1.00")) and the upper limit T max 6, the conversion unit 330 decreases the rotation speed of the rotation take-in unit 11 (downward change in FIG. 6) in response to an increase in load / torque (change to the right in FIG. 6).

[0043] For example, if a large amount of highly fluid bulk material M, such as white pellets, flows in through the rotary intake section 11, the load on the screw conveyor 90 may increase suddenly. In such a case, as shown in Figure 6, the conversion section 330 reduces the rotational speed of the rotary intake section 11, thereby reducing the amount of bulk material M taken into the screw conveyor 90 through the rotary intake section 11, and the high load state of the screw conveyor 90 is effectively eliminated.

[0044] In the example shown, T th ~T maxIn the section, the rotation speed decreases linearly (i.e., in a straight line) with respect to the load / torque, but the rotation speed may decrease nonlinearly (i.e., in a curved line) with respect to the load / torque.

[0045] The load / torque input from the division unit 320 is the upper limit load T max When the rotation speed reaches the upper limit load T, the conversion unit 330 forcibly sets the rotation speed to "0" to stop the rotation of the rotation take-in unit 11. In this way, according to the control device 300 of this embodiment, when the screw conveyor 90 is in an overload state (when the load of the screw conveyor 90 reaches the upper limit load T), max In the event of a situation where the rotational intake section 11 is in an emergency (a situation where the rotational intake section 11 is in an emergency state), the control device 300 can quickly and safely bring the rotational intake section 11 to an emergency stop. Note that the control device 300 may bring the screw conveyor 90 to an emergency stop in addition to or instead of bringing the rotational intake section 11 to an emergency stop.

[0046] On the other hand, when the load / torque input from the division unit 320 is less than the predetermined adjustment-free threshold T th , the conversion unit 330 detects at least a certain load range (in the example of FIG. 6, "0" and T th The rotation speed of the rotation capture unit 11 may be kept substantially constant throughout the entire range between 0 and 1000 (the entire range between 0 and 10000). For example, the rotation speed of the rotation capture unit 11 is kept substantially constant by controlling the desired rotation speed (rotation speed command value) of the rotation capture unit 11 as the output of the conversion unit 330 to be constant. In the example of FIG. 6, the conversion unit 330 controls the rotation speed of the rotation capture unit 11 to be substantially constant throughout the entire range between 0 and 10 ... th In the following load range, the rotation speed of the rotation intake portion 11 is set to a constant maximum speed N max If T th ~T max As with the section, "0" to T th If the rotation speed is monotonically decreased with respect to the load / torque even in the section T, the rotation speed of the rotation take-in section 11 may become excessively high, especially for the load / torque in the vicinity of "0". th In the following range, the rotation speed of the rotational intake section 11 is limited to an upper limit N max On the other hand, if there is no possibility that the rotation speed of the rotation take-in portion 11 becomes excessively high, it is preferable to set the upper limit value N max There is no need to set

[0047] 3, a multiplication unit 340 multiplies the output from the conversion unit 330 by a predetermined reference value 341. This reference value 341 is used to convert the dimensionless quantity output from the conversion unit 330 into an actual dimensional quantity of the desired rotation speed of the rotation take-in unit 11. In this way, the desired rotation speed of the rotation take-in unit 11 according to the load / torque detected by the screw conveyor load detection unit 310 is obtained via the multiplication unit 340.

[0048] The reference value 341 of the rotation speed of the rotation take-in unit 11 can be set arbitrarily. As illustrated in Fig. 6, the reference value 341 may be set to N0 corresponding to T0, which is the reference value 321 for the load / torque. In this case, when the motor 60 outputs the reference torque T0 ("1.00" on the horizontal axis in Fig. 6), the desired rotation speed of the rotation take-in unit 11 becomes the reference rotation speed N0 ("1.00" on the vertical axis in Fig. 6). However, the reference value 341 (N0) for the rotation speed of the rotation take-in unit 11 may be set independently of the reference value 321 (T0) for the load / torque.

[0049] The rotation speed command unit 350 commands the inverter 51 to the desired rotation speed of the rotation taker 11 calculated by the multiplication unit 340. The inverter 51 supplies AC power based on the rotation speed command to the motor 50, which serves as an AC motor. The motor 50 drives and rotates the rotation taker 11 at the rotation speed commanded by the rotation speed command unit 350. Note that the motor 50 may be a DC motor that drives and rotates the rotation taker 11 based on DC power. In that case, a DC power supply unit capable of supplying the DC power based on the rotation speed command from the rotation speed command unit 350 is provided instead of the inverter 51.

[0050] In the control device 300 as described above, the division unit 320, conversion unit 330, multiplication unit 340, and rotational speed command unit 350 collectively constitute an intake rotational speed adjustment unit 400 that adjusts the rotational speed of the rotary intake unit 11 in accordance with the load detected by the screw conveyor load detection unit 310.

[0051] As described above, particularly with reference to FIG. 6, the intake rotation speed adjusting unit 400 reduces the rotation speed of the rotary intake unit 11 in response to an increase in the load detected by the screw conveyor load detecting unit 310 (T th ~T max The intake rotation speed adjusting unit 400 adjusts the rotation speed of the screw conveyor 100 when the load detected by the screw conveyor load detecting unit 310 is equal to or exceeds a predetermined upper limit load T max When the load detected by the screw conveyor load detection unit 310 reaches a predetermined adjustment-free threshold T th If the rotation speed of the rotation intake portion 11 is lower than the predetermined value, the rotation speed of the rotation intake portion 11 is kept substantially constant (N max )

[0052] The present disclosure has been described above based on the embodiments. Various modifications are possible to the combinations of the components and processes in the exemplary embodiments, and it will be obvious to those skilled in the art that such modifications are included within the scope of the present disclosure.

[0053] The configuration, operation, and function of each device and method described in the embodiments can be realized by hardware resources, software resources, or a combination of hardware and software resources. Examples of hardware resources include processors, ROMs, RAMs, and various integrated circuits. Examples of software resources include operating systems, applications, and other programs. [Explanation of symbols]

[0054] 1 Unloading machine (VSC), 9 Unloading section, 11 Rotational intake section, 50 Motor, 51 Inverter, 60 Motor, 61 Inverter, 90 Screw conveyor, 300 Control device, 310 Screw conveyor load detection section, 330 Conversion section, 350 Rotational speed command section, 400 Intake rotational speed adjustment section.

Claims

1. A control device for a lifting machine including a rotary intake section that rotates around an intake rotation axis and takes in cargo along the circumferential direction of the intake axis, and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotary intake section along the axial direction of the screw rotation axis, a screw conveyor load detection unit that detects the load of the screw conveyor; an intake rotation speed adjusting unit that adjusts the rotation speed of the rotation intake unit in accordance with the load detected by the screw conveyor load detecting unit; A control device for a lifting machine comprising:

2. 2. The control device for a lifting machine according to claim 1, wherein the take-in rotation speed adjusting unit reduces the rotation speed of the rotary take-in unit in response to an increase in the load detected by the screw conveyor load detecting unit.

3. 3. The control device for a lifting machine according to claim 2, wherein the take-in rotation speed adjusting unit stops the rotation of the rotary take-in unit when the load detected by the screw conveyor load detecting unit reaches a predetermined upper limit load.

4. 4. The control device for a lifting machine according to claim 2 or 3, wherein the intake rotational speed adjustment unit keeps the rotational speed of the rotary intake unit substantially constant at least within a certain load range when the load detected by the screw conveyor load detection unit falls below a predetermined adjustment-free threshold.

5. 4. A control device for a hoisting machine according to claim 1, wherein the screw conveyor load detection unit detects the load on the screw conveyor based on a current of a motor that rotates and drives the screw conveyor.

6. The control device for a lifting machine according to any one of claims 1 to 3, wherein the cargo is biofuel or grain.

7. A lifting machine comprising: a rotary intake section that rotates around an intake rotation axis and takes in cargo along the circumferential direction of the axis; and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotary intake section along the axial direction of the axis, a screw conveyor load detection unit that detects the load of the screw conveyor; an intake rotation speed adjusting unit that adjusts the rotation speed of the rotation intake unit in accordance with the load detected by the screw conveyor load detecting unit; A lifting machine equipped with:

8. A control method for a lifting machine including a rotary intake section that rotates around an intake rotation axis and takes in cargo along the circumferential direction of the intake axis, and a screw conveyor that rotates around a screw rotation axis and transports the cargo taken in by the rotary intake section along the axial direction of the screw rotation axis, comprising: Detecting a load on the screw conveyor; adjusting a rotation speed of the rotary take-up portion in response to the detected load; A method for controlling a lifting machine that performs the above.

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