JPH0853290A - Crane hanging monitor device - Google Patents

Abstract

PURPOSE:To stably monitor a hanging load by providing a drive variable control means for controlling the drive variable of a hanging load monitor camera drive means, so as to ensure that a monitor camera always follows the hanging load, in response to a value detected with a boom state detection means. CONSTITUTION:A hanging load monitor camera control unit 40 has a ROM 33 for storing control data, and a RAM 34 for sequentially saving and reading out boom elevation angles detected with a boom elevation angle detection means 24 after A/D conversion. Also, signals detected with and transmitted from a potentiometer 38 for detecting such an actual monitor angle of a hanging load monitor camera as changing depending on the number of revolutions of a hanging load monitor camera drive motor 37, are subjected to A/D conversion and saved in the RAM 34 via a hanging load monitor camera control unit 40. According to this construction, the rotating direction and the speed of the motor are controlled, so as to correspond to a boom elevation angle variation, so that the camera can always photograph the positions of a hook and the load, regardless of the variation, and the load monitor angle of the camera is accurately controlled variably at a target monitor angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspended load monitoring device for a crane.

[0002]

2. Description of the Related Art Generally, a crane is used for hoisting and hoisting a desired target load in various works such as construction, civil engineering, and heavy object installation.

However, when performing the hoisting work, depending on the work place, for example, as shown in FIG. 16, the slinging work position P ₁ side of the hoisting load 21 below the tip of the boom 3 and the driver's seat P _{2 are shown.}
There may be a fence or other obstacle 50 of a predetermined height between the side and the side, and it may not be possible to see the state of sling or suspended load from the driver's seat P ₂ side. In such a case, it is very dangerous to operate the boom with a proper guess.

For this reason, conventionally, for example, a crane driver and a slinging worker both carry a communication means such as a transceiver so as to safely carry out slinging or hanging work while mutually communicating and confirming.

However, in the slinging work, first, it is necessary to accurately hang the hook at the position of the center of gravity of the wire on the side of the suspended load 21. For that purpose, it is not inconvenient for the telephone call and the instruction work by the transceiver. There is a problem that accurate slinging work cannot be performed in a short time. In addition, since the state of the suspended load 21 cannot be surely recognized even during the suspended load work after the sling is completed, it is difficult to secure a safe operation.

Therefore, recently, for example, Japanese Patent Publication No. 2-348.
As disclosed in Japanese Patent Laid-Open No. 80, there is also provided a television camera provided at the tip of the boom and an image captured by the television camera is displayed on a monitor television provided on the crane driver's side. From the above, by performing the crane operation while constantly monitoring the state of the suspended load side using the TV camera, it is possible to perform the hook drop to the exact suspended load center position and the safe and secure suspended load work. It is possible to do it. This not only enables accurate and quick slinging work, but also lifting and
Since the state of the suspended load can always be reliably monitored even when the crane is hoisted, there are great advantages such as being able to secure safe crane operation work. It also makes driving easier.

[0007]

However, when the structure is adopted, the following various problems to be solved arise.

(1) The television camera provided at the tip of the boom (hereinafter, referred to as a suspended load monitoring camera in accordance with the above-mentioned use) always faces vertically downward from the boom tip (suspended load and hook direction). Therefore, for example, the rear end of the hanging load monitoring camera is rotatably hung with respect to the boom front end portion via a rotation supporting means such as a hinge mechanism,
It is conceivable that the weight of the objective lens always directs the objective lens side downward in the vertical direction.

However, when such a structure is adopted,
The suspended load monitoring camera may sway due to wind or other circumstances, and it is not always possible to accurately fix the imaging direction downward in the vertical direction. Therefore, there remains a problem that stable suspended load cannot be monitored.

(2) In order to solve the problem of (1), for example, the hanging load monitoring camera is connected to a motor shaft, and the motor is drive-controlled to constantly monitor the direction of the hanging load. It is possible to do it.

However, in such a case, the parameters that change according to the crane operating condition such as the boom hoisting angle of the crane, the boom hoisting angle, the boom length and the amount of boom flexure that depends on the load are properly considered. Without this, accurate supervisory control cannot be realized.

(3) Further, the suspended load monitoring camera is not always provided at the tip of the top boom, and generally, it is easier to install and the wiring can be shortened if it is provided at the tip of the base boom.

However, in such a case, the suspended load position changes depending on the boom hoisting angle, the boom length, the wire feeding length, and the like, so that a highly accurate monitoring angle corresponding to them can be obtained.
(Elevation angle) control is required.

An object of the present invention is to provide a suspended load monitoring device for a crane, which appropriately solves various problems as described above.

[0015]

The present invention comprises the following problem solving means in order to achieve the object.

That is, the crane suspended load monitoring apparatus of the present invention comprises a base, a swivel rotatably provided on the base, and a boom supported by the swivel so as to be capable of elevating and retracting. A winch provided on the swivel base, a wire extending from the winch along the boom, and vertically extending downward from the tip side of the top boom, and a sling provided on the lower end of the wire. Hook, a suspended load monitoring camera rotatably provided at the tip of the top boom of the boom, a monitor TV provided in the driver's seat on the base side showing an image of the suspended load monitoring camera, In a crane comprising a load monitoring camera driving means for rotating and driving a load monitoring camera in a hanging direction, a boom state detecting means for detecting a boom state and a detected value of the boom state detecting means are provided. To be constructed by providing a drive amount control means for controlling the driving amount of the suspended load monitoring camera drive means so as to follow the suspended load monitoring camera is always suspended load.

Further, the boom state detecting means in the configuration is, for example, a boom hoisting angle detecting means for detecting a boom hoisting angle, and the drive amount controlling means determines the boom hoisting angle detected by the boom hoisting angle detecting means. Correspondingly, it is configured to control the drive amount of the suspended load monitoring camera drive means, and as another configuration, for example, load detection means for detecting the load of the suspended load is added to the boom hoist angle detection means. The drive amount control means drives the suspended load monitoring camera in consideration of the bending amount of the boom determined by the boom hoisting angle detected by the boom hoisting angle detecting means and the load detected by the load detecting means. It is arranged to control the drive amount of the means.

Further, in addition to the boom hoisting angle detecting means and the load detecting means, the boom state detecting means in the above construction is further provided with a boom length detecting means for detecting the length of the boom. A more accurate boom deflection amount is calculated based on the boom hoisting angle, the suspended load, and the boom length detected by the boom hoisting angle detection means, the load detection means, and the boom length detection means. It is configured to control the drive amount of the suspended load monitoring camera drive means with higher accuracy.

Further, the crane hanging load monitoring apparatus of the present invention includes a base, a swivel rotatably provided on the base,
A boom supported by the swivel so as to be undulated and extendable, a winch provided on the swivel, and a winch extending from the winch along the boom so that the boom can be vertically moved downward from the tip end side of the top boom. A suspended wire, a hook for slinging provided at the lower end of the wire, a suspended load monitoring camera rotatably provided at a boom tip other than the top boom of the boom, and a suspended load monitoring camera of the suspended load monitoring camera. Boom condition in a crane comprising a monitor TV provided in the driver's seat on the base side for displaying an image, and a suspended load monitoring camera driving means for rotationally driving the suspended load monitoring camera in the hanging direction. And a drive control unit for controlling the drive amount of the suspended load monitoring camera drive unit so that the suspended load monitoring camera always follows the suspended load in accordance with the detection value of the boom state detection unit. It is constructed by providing a quantity control means.

Further, the boom state detecting means in the construction comprises, for example, a boom hoisting angle detecting means, a boom length detecting means, and a wire feeding length detecting means, and the drive amount controlling means is the boom hoisting angle detecting means, the boom. The amount of drive of the suspended load monitoring camera drive means is appropriately set according to the suspended load position determined by the boom detection angle, the boom length, and the extended wire length detected by the length detection means and the wire delivery length detection means. Configured to control.

[0021]

The crane suspended load monitoring apparatus according to the present invention has the following functions corresponding to the above-mentioned configuration.

That is, in the configuration of the crane hanging load monitoring device of the present invention, as described above, the base, the swivel rotatably provided on the base, and the undulation and expansion / contraction with respect to the swivel. A boom that is movably supported, a winch that is provided on the swivel base, a wire that extends from the winch along the boom, and that vertically extends downward from the tip side of the top boom, and the wire. A hook for slinging provided at the lower end of the boom, a suspended load monitoring camera rotatably provided at the tip of the top boom of the boom, and a driver seat provided on the base side for displaying an image of the suspended load monitoring camera. In a crane comprising a monitor television and a hanging load monitoring camera driving means for rotating the hanging load monitoring camera in the hanging direction, a boom state detecting means for detecting a boom state, and a boom state detecting means for detecting the boom state. The suspended load monitoring camera is provided with drive amount control means for controlling the drive amount of the suspended load monitoring camera drive means so that the suspended load monitoring camera always follows the suspended load in correspondence with the detection value of the detection means, and the boom state The drive amount control unit appropriately controls the drive amount of the suspended load monitoring camera drive unit, that is, the monitoring angle in the suspended load direction, corresponding to the actual operating state of the boom detected by the detection unit.

Therefore, the suspended load monitoring camera can always automatically and accurately point the suspended load direction even if the operating state of the boom changes.

In this case, the boom state detecting means comprises a boom hoisting angle detecting means for detecting a change in boom hoisting angle, and the drive amount controlling means detects the boom hoisting angle detected by the boom hoisting angle detecting means. When the drive amount of the suspended load monitoring camera drive means is controlled in response to the change, the suspended load monitoring camera always points in the direction of the suspended load in response to the change in boom hoisting angle. The monitoring angle can be controlled accurately.

Further, in the above case, the boom state detecting means comprises the boom hoisting angle detecting means and the load detecting means, and the drive amount controlling means controls the boom hoisting angle detected by the boom hoisting angle detecting means. When the amount of bending of the boom itself determined by the change and the load of the suspended load detected by the load detection means at that time is taken into consideration, the drive amount of the suspended load monitoring camera drive means is controlled. In addition to the hoisting angle, a more appropriate monitoring angle control of the hanging load monitoring camera is realized by canceling the change in the monitoring angle due to the amount of bending of the boom that occurs corresponding to the load of the hoisting load under the boom hoisting angle.

Further, in addition to the boom hoisting angle detecting means and the load detecting means, the boom state detecting means in the above structure is further provided with a boom length detecting means for detecting the length of the boom, and the drive amount control is performed. The means calculates a more accurate boom deflection amount based on the boom hoisting angle, the load detecting means, the boom hoisting angle detected by the boom length detecting means, the suspended load, and the boom length. When the driving amount of the hanging load monitoring camera drive means is configured to be controlled with higher accuracy, a more accurate hanging load monitoring camera that takes into account the amount of boom bending that also changes due to changes in the boom length can be provided. Monitoring angle control is realized.

Further, in the construction of the crane hanging load monitoring device of the present invention, as described above, the base, the swivel rotatably provided on the base, and the undulating and expanding / contracting with respect to the swivel. A boom supported by the winch, a winch provided on the swivel base, a wire extending from the winch along the boom, and vertically extending downward from the tip side of the top boom, and a wire of the wire. A hook for slinging provided at the lower end, a hanging load monitoring camera rotatably provided at a boom tip other than the top boom of the boom, and a driver seat on the base side showing an image of the hanging load monitoring camera. In a crane comprising a monitor television provided and a suspended load monitoring camera driving means for driving the suspended load monitoring camera to rotate in the suspended direction, boom state detection means for detecting a boom state, and Bu The suspended load monitoring camera provided at the tip of a boom other than the top boom, such as the base boom tip, controls the drive amount of the suspended load monitoring camera drive means in accordance with the detected value of the boom state detection means so as to always follow the suspended load. And a drive amount control means for controlling the amount of drive of the suspended load monitoring camera drive means by the drive amount control means corresponding to the actual operation state of the boom detected by the boom state detection means. That is, the monitoring angle from the boom tip position other than the top boom to which the suspended load monitoring camera is attached to the suspended load direction is appropriately controlled.

Therefore, the hanging load monitoring camera always automatically points the direction of the hanging load even when the operating state of the boom changes.

In this case, the boom state detecting means comprises, for example, a boom hoisting angle detecting means, a boom length detecting means, a wire feeding length detecting means, and the drive amount controlling means has the boom hoisting angle detecting means. , The boom length detection means, the wire feed length detection means, respectively, the boom hoisting angle, the boom length, and the wire feed length determined by the wire feed length. If it is configured to be controlled in accordance with the boom hoisting angle, the boom length, and the wire feed length, for example, the base boom tip, such as the base boom tip, the hoist from a boom tip other than the top boom equipped with a load monitoring camera is installed. The load position is always accurately specified, and the monitoring angle of the suspended load monitoring camera is accurately controlled accordingly.

[0030]

As a result of the above, according to the crane suspended load monitoring apparatus of the present invention, the camera monitoring position can always be fixed in a stable state without being affected by wind or the like, and the boom can be operated. Regardless of a change in state, a change in the amount of flexure of the boom corresponding thereto, a change in the elevating position of the suspended load, and the like, the monitoring direction of the camera can always be made to accurately follow the change. Therefore, the above-mentioned technical problems (1) to (3) of the related art are reliably solved.

[0031]

【Example】

(Embodiment 1) In FIGS. 1 to 8, a suspended load monitoring camera is provided downward at the tip of the top boom, and the suspended load monitoring camera is made to always follow the suspended load direction regardless of changes in the boom hoisting angle. The configuration and operation of the suspended load monitoring device for a crane according to the first embodiment of the present invention as described above are shown.

In this embodiment, the crane shown in FIG.
As shown in FIG. 1, a mobile crane is provided in which a swivel base 2 is provided on a chassis 1a of a vehicle 1, and a boom 3 is installed on the swivel base 2 via a hinge portion 4 so that the boom 3 can be lifted and lowered.
Outriggers 5F and 5R are provided on the front and rear ends of the chassis 1a of the vehicle 1, respectively.

The boom 3 is composed of, for example, a four-stage telescopic boom, and three booms including a second boom 3b, a third boom 3c, and a top boom 3d with respect to the base boom 3a supported by the swivel base 2. The telescopic booms are sequentially inserted so that they can be expanded and contracted. Top boom 3 above
The boom head portion 12 of d is provided with an additional boom such as a jib if necessary.

The boom 3 is the base boom 3a.
By the expansion / contraction control of the hoisting cylinder 6 provided between the swivel base 2 and the swivel base 2, hoisting operation can be arbitrarily performed from the state of the minimum hoisting angle to the maximum hoisting angle or from the state of the maximum hoisting angle to the minimum hoisting angle.

Further, a winch 7 is provided at the rear end portion of the swivel base 2 on the counterweight side, a sheave 8 for wire guide is provided on the upper surface of the base boom 3a at the tip end side thereof, and a tip of the top boom 3d is further provided. The upper sheave 9 is provided above and below the side boom head 12 as shown in FIGS.
And a lower sheave 10 are provided respectively. Then, the wire 11 unwound from the drum portion of the winch 7
However, as shown in the figure, it is hung vertically from the boom head portion 12 through the sheaves 8, 9 and 10, and a hook 13 for slinging is provided at the tip thereof.

On the other hand, reference numeral 15 is a suspended load monitoring camera provided downward on one side of the boom head 12.
As shown in FIG. 3, the suspended load monitoring camera 15 is provided so as to be located between the upper and lower sheaves 9 and 10 of the boom head 12, and has a drive shaft 37a protruding laterally from the suspended load monitoring camera drive motor ( Hereinafter, the rear end of the main body side is fixed to the drive shaft 37a of the motor 37 via the bracket 15a and is supported so as to be rotatable in the arrow (a) or (b) direction in FIG. Cage, the boom 3 is undulated and expanded / contracted, the boom is bent due to the relationship between the boom 3 and the load W of the suspended load 21, and the positions of the hook 13 and the suspended load 21 are followed according to the vertical movement of the hook 13 and the suspended load 21. Then, it is designed to monitor those conditions appropriately. When the motor 37 rotates to the right, the suspended load monitoring camera 15
Rotates in the direction of arrow (b), and when it rotates counterclockwise, it rotates in the direction of arrow (a).

Further, reference numeral 14 is an operating room of the mobile crane, and the operating room 14 is provided on one side of the swivel base 2. The operator's cab 14 is provided with various operating means for operating a crane and a vehicle, and the instrument panel has a monitor TV 20 as shown in FIG. 4, for example. The states of the hook 13 and the suspended load 21 captured by the surveillance camera 15 are displayed on the screen 20a of the monitor TV 20.

The crane is provided with a boom hoisting angle detecting means 24 for detecting the hoisting angle θ of the boom 3 and an extension length L of the boom 3 as shown in FIGS. Boom length detecting means 26 for detecting, load detecting means 27 for detecting the hanging load W of the hanging load 21, wire feeding length detecting means 28 for detecting the feeding length A of the wire 11 from the boom head 12, and the like. Various sensors are provided respectively.

The crane having the above structure is shown in FIG.
It is used in a state in which an obstacle 50 such as a fence is interposed.

Next, FIG. 5 shows the construction of the control circuit section of the suspended load monitoring apparatus in the mobile crane of this embodiment.

The control circuit uses the suspended load monitoring camera 15 described above.
However, the hook 1 is always attached regardless of the fluctuation of the boom hoisting angle θ.
3 and the position of the suspended load 21 are appropriately controlled in response to changes in the boom hoisting angle θ so that the rotation direction and the rotational speed of the motor 37 are controlled, whereby the suspended load monitoring camera 15 suspends the suspended load. The monitoring angle (suspended load monitoring direction) is accurately and variably controlled to the target monitoring angle.

That is, first, reference numeral 40 in the figure is a suspended load monitoring camera control unit which is composed of, for example, a microprocessor, and the suspended load monitoring camera control unit 40 is shown in FIG.
In addition to the control program of the present embodiment as shown in FIG. 3, the read-only memory (ROM) 33 that stores various control data necessary for the control and the boom hoisting angle detection means 24 detect the A / D converter 25. A random access memory (RAM) 34 for sequentially storing at least the previous value θn- ₁ and the current value θn- ₁ , etc. of the boom hoisting angle θ A / D converted via the RAM and reading them as needed is provided. Is configured.

Reference numeral 36 is a drive circuit for the above-mentioned hanging load monitoring camera drive motor 37. The motor drive circuit 3
Reference numeral 6 is a first and a second that change the direction of rotation by arbitrarily connecting the field terminals of the motor 37 to two sets of power source side or earth side terminals provided so as to have opposite polarities in opposite directions. The relay relays S ₁ and S ₂ are provided, and the connection state that determines the polarity of the first and second relay contacts S ₁ and S _{2 with} the power source side or the earth side terminal is the switching relay 41. The state is sequentially switched to the opposite state according to the excitation and de-excitation operation of. The energized and de-energized operating states of the switching relay 41 are controlled by a control output signal from the suspended load monitoring camera control unit 40.

Further, reference numeral 35 is a power source (+ B) common to the two power source terminals of the motor drive circuit 36 during the ON period.
Power supply switch 35 for turning on and off the power switch 35.
It is controlled by a power switch control signal from 0.

Further, reference numeral 38 is a potentiometer for detecting the actual monitoring angle (rotation angle) of the hanging load monitoring camera 15 which changes according to the number of rotations (rotation time) of the hanging load monitoring camera drive motor 37, The detection signal of the potentiometer 38 is A / D converted by the A / D converter 39 and then stored in the random access memory 34 through the suspended load monitoring camera control unit 40. The hanging load monitoring camera control unit 40 determines that the monitoring angle of the hanging load monitoring camera 15 detected by the potentiometer 38 has reached the target monitoring angle variable value, and turns off the power switch 35. To do.

Next, FIG. 6 shows the contents of the suspended load monitoring angle control (suspended load tracking control) of the suspended load monitoring camera 15 according to the change of the boom hoisting angle θ by the suspended load monitoring camera control unit 40 of FIG. 7 and 8 show the operating states of the boom 3 corresponding to the control.

For example, as shown in FIG. 7 and FIG. 8 from the state of the phantom line to the state of the solid line, when the hoisting angle θ of the boom 3 changes in the expanding or contracting direction (θn- _{1 to} θn), the boom is naturally 3 and the hanging direction of the suspended load 21 (suspending direction vertical line), that is, the suspended load monitoring angle ω (ω = 90 °-
θ) also changes (ωn− _{1 to} ωn).

Therefore, as described above, a relatively wide-angle suspended load monitoring camera 15 is installed at the tip of the boom 3 toward the hook 13 and the suspended load 21, and the states of the hook 13 and the suspended load 21 are always accurately monitored. to the suspended load monitoring angle of the hanging load monitoring camera 15 (omega) also changes in the boom hoisting angle θ as described above appropriately changes according to _{(θn- 1 ~θn) (ωn- 1} ~ω
n) Need to be done. The flowchart of FIG. 6 is configured from such a viewpoint.

That is, when the control circuit of FIG. 5 is turned on, the control operation of the hanging load monitoring camera control unit 40 is started correspondingly, and first, in step S ₁ , the boom hoisting angle detecting means 24 is operated. Present detected in (Fig. 7,
The boom hoisting angle detection value θn (in the state shown by the solid line in FIG. 8) is input.

Next, in step S ₂ , the current boom hoisting angle detection value θn that has been input is temporarily stored in the random access memory (RAM) 34.

After that, the process further proceeds to step S ₃ , and the boom undulation detected in the previous control cycle (state of the virtual line in FIGS. 7 and 8) previously stored in the random access memory (RAM) 34 is detected. Read angle θn- ₁ .

Then, in step S ₄ , the current boom hoisting angle detection value θn and the previous boom hoisting angle detection value θn- _1.
Are equal to each other, that is, whether or not there is a change in the boom hoisting angle θ in either the expansion direction or the contraction direction.

As a result, when YES is determined, that is, during the previous control and the current control, there is no change in the hoisting angle θ of the boom 3 itself, and the same hoisting angle θ (θ = θn =
If only the raising / lowering operation of the hook 13 or the suspended load 21 itself is performed under θn- ₁ ) or only the extension / contraction operation of the boom 3 is performed in the same state, the setting control is performed in the previous follow-up control. Since it is not necessary to change the suspended load monitoring angle ωn− ₁ of the suspended load monitoring camera 15 that is in progress, the control of the cycle is ended as it is.

On the other hand, on the contrary, when the determination in step S ₄ is NO, that is, the boom hoisting angle θ is in either the expansion direction or the contraction direction from the previous control to the current control. when changing the predetermined angle Δθ, the subsequently proceeds to step S _5, the current boom hoisting angle detection value θn
Is greater than the previous boom hoisting angle detection value θn− ₁ , that is, the current hoisting angle θn is the previous boom hoisting angle θn.
-Determine whether it has changed in the expansion direction or in the reduction direction when viewed from ₁ .

As a result, when the determination is YES, that is, when the change is made in the expanding direction as shown in FIG. 7, it is necessary to reduce the suspended load monitoring angle ω. Therefore, the process first proceeds to step S ₆ and the switching relay 41 is operated. Is excited to switch the first and second relay contacts S ₁ and S ₂ of the motor drive circuit 36 to the motor left rotation side power source polarity in the hanging load monitoring angle reduction direction, and then the process proceeds to step S ₇ . , The angle of change Δθ (Δθ = θn−θn− ₁ ) in the direction of expansion from the previous time to the current time of the current boom hoisting angle θn
Then, the reduction angle Δω ₁ of the suspended load monitoring angle ω is calculated.

Here, the boom hoisting angle θn from the previous time is
- suspended load monitoring angle Omegaenu- ₁ under the _1, ωn- ₁ = 90 °
−θn− ₁ , and the suspended load monitoring angle ωn below the boom hoisting angle θn this time is represented by ωn = 90 ° −θn. Therefore, after all, the reduction angle Δω ₁ of the suspended load monitoring angle ω corresponding to the change in the boom hoisting angle θ is equal to the boom hoisting angle θ.
Is equal to the change Δθ of Δω ₁ = θn−θn− ₁ .

Then, in the following step S ₁₀ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the counterclockwise rotation direction of the motor. As a result, the hanging load monitoring camera drive motor 37 rotates counterclockwise and the hanging load monitoring camera 1
The monitoring angle ω of 5 is reduced and controlled so as to match the actual direction of the hook 13 or the suspended load 21.

Further, proceeding to step S ₁₁ , in the suspended load monitoring angle reduction control state, the actual movement angle Δω ₂ of the suspended load monitoring camera 15 is detected based on the output of the potentiometer 38, and in the subsequent step S ₁₂ . , Whether the actual movement angle detection value Δω ₂ is equal to the calculated value Δω ₁ which is the target drive angle, that is, whether the hanging load monitoring camera 15 is actually driven by the target drive angle Δω _{1 in the} reduction direction. To determine.

As a result, in the case of NO, that is, when the actual drive angle Δω ₂ is not yet reduced and driven by the target drive angle Δω ₁ , the power switch 35 of the step S ₁₀ is turned ON.
Control, detection of Δω ₂ in steps S ₁₁ and S ₁₂ , Δω ₂ = Δω ₁
? The determination control of is continued and Δω ₂ = Δω in step S _12.
When it is determined to be ₁ (YES), that is, the suspended load monitoring camera 15
Is actually reduced by the target drive angle Δω ₁ , the process proceeds to step S ₁₃ for the first time, the power switch 35 is immediately turned off, and the driving of the hanging load monitoring camera drive motor 37 is stopped.

As a result, the suspended load monitoring camera 15 is rotated inwardly (the direction (a) in FIG. 2) to accurately reduce the monitoring angle ω in response to the expansion of the boom hoisting angle θ, and the hook is truly hooked. 1
3 and the downward direction corresponding to the directions of the suspended load 21 are made to follow, and it becomes possible to appropriately monitor the hook 13 and the suspended load 21 as shown by the solid line in FIG.

On the other hand, when the result of the comparison between the present and the previous boom hoisting angle in step S ₅ is NO, when the change in the hoisting angle reducing direction as shown in FIG. Since it is necessary to increase the load monitoring angle ω, the process first proceeds to step S ₈ to excite the switching relay 41,
The first and second relay contacts S ₁ and S ₂ of the motor drive circuit 36
After switching to a motor rightward rotation power supply polarity suspended load monitoring angle increasing direction and the process proceeds to step S _9, the change in angle [Delta] [theta] from the previous current boom hoisting angle θn to shrink direction to the current ([Delta] [theta] = The expansion angle Δω ₁ of the suspended load monitoring angle ω corresponding to θn − _{1 −} θn) is calculated.

Here, here, the previous boom hoisting angle θn
- suspended load monitoring angle Omegaenu- ₁ under the _1, as in the case of the ωn- ₁ = 90 ° shown in -Shitaenu- _1, also suspended load monitoring angle ωn under the current boom hoisting angle θn , Ωn = 90
It is indicated by ° -θn. Therefore, after all, the enlargement angle Δω ₁ of the suspended load monitoring angle ω corresponding to the change in the boom hoisting angle θ is equal to the change Δθ in the boom hoisting angle θ, and Δω ₁ = θn−θ
It is calculated as n- ₁ .

Then, in the subsequent step S ₁₀ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the motor clockwise direction. As a result, the hanging load monitoring camera drive motor 37 rotates to the right, and enlargement control is performed so that the monitoring angle ω of the hanging load monitoring camera 15 matches the actual direction of the hook 13 or the hanging load 21.

[0064] Further, the process proceeds to step S _11, in該監viewing angle enlargement control state, similarly to the above case, to detect the movement angle [Delta] [omega ₂ of the actual suspended load monitoring camera 15 based on the output of the potentiometer 38, followed by in step S _12, whether or not the mobile angle detected value [Delta] [omega ₂ of said actual is equal to the target driving angle [Delta] [omega _1, i.e. actually do suspended load monitoring camera 15 is driven to the expansion direction by the target drive angle [Delta] [omega ₁ not To determine.

As a result, in the case of NO, that is, when the actual movement angle Δω ₂ is not yet driven in the expansion direction by the target drive angle Δω ₁ , the power switch 35 in step S ₁₀ described above.
Control ON, the step S _11, the detection of [Delta] [omega ₂ of S _12, [Delta] [omega ₂
= Δω ₁ ? The determination control continues to step S ₁₂ in [Delta] [omega ₂ =
When it is determined to be Δω ₁ (YES), that is, when the suspended load monitoring camera 15 is actually enlarged and driven to the target drive angle Δω ₁ , the process proceeds to step S ₁₃ and the power switch 35 is immediately turned off to suspend the suspended load. The drive of the surveillance camera drive motor 37 is stopped.

As a result, the suspended load monitoring camera 15 is rotated in the outward direction (the direction (b) in FIG. 2) so as to accurately increase the suspended load monitoring angle in response to the reduction of the boom hoisting angle θ. Figure 8
As shown by the solid line in FIG.
Therefore, the hook 13 and the hanging load 21 can be appropriately monitored.

Then, the control is repeated at a predetermined cycle.

In the above description, when the suspended load monitoring angle ω is variably controlled by Δω _{1 in} accordance with the change Δθ in boom hoisting angle θ, first, the suspended load monitoring camera drive motor 37 is driven and the potentiometer 38 is used. The hanging load monitoring camera drive motor 37 is configured to be stopped when the actually detected movement angle Δω ₂ becomes equal to the target driving angle Δω _1. However, variable control of the hanging load monitoring angle ω is performed. As another method, for example, the driving time of the hanging load monitoring camera drive motor 37 corresponding to the target driving angle Δω ₁ is set, and when the driving time elapses, the power of the hanging load monitoring camera drive motor 37 is turned off. It goes without saying that it may be configured to stop.

(Embodiment 2) Next, FIGS. 9 to 11 show the construction of a crane suspended load monitoring apparatus according to Embodiment 2 of the present invention.

In the construction of this embodiment, for example, as shown in FIG. 9, the extension length of the boom 3 is further increased as compared with the construction of the control circuit of the first embodiment shown in FIG. Boom length detecting means 26 for detecting L and load detecting means 27 for detecting the load W of the suspended load 21 are added respectively, and the detection signals of the respective detecting means 24, 26, 27 are respectively A / D converters. A / D conversion is performed at 25 to input to the suspended load monitoring camera control unit 40, and based on three detection parameters of the boom hoisting angle θ, the boom length L, and the load W of the suspended load, the boom concerned. Hoisting angle θ, boom length L,
In order to perform more appropriate suspended load monitoring angle control (suspended load follow-up control) of the suspended load monitoring camera 15 in consideration of the bending angle M of the boom 3 as shown in FIG. 11 which is determined by the suspended load W. It is characterized by having done.

That is, as shown in FIG. 11, for example,
The boom 3 of the crane has no load W of the suspended load 21, for example.
At the time of (W = 0), even when there is no bending like the phantom line B ₁ (boom hoisting angle θn− ₁ , boom length Ln− ₁ ), when the load W of the suspended load 21 is actually applied, resulting in deflection of the predetermined angle Mn- _1, for example, as the solid line B ₂ state. The size of該撓body, in addition to the magnitude of the load W, vary depending boom hoisting angle Shitaenu- ₁ and the boom length L n ₁ at that time.

On the other hand, the load W of the suspended load 21 is
Even if the angle is constant, the boom hoisting angle θ is indicated by the imaginary line B ₁
When θn- _{1 in the} state becomes smaller than θn in the phantom line B ₃ state, it means that the deflection angle is also expanded from Mn- ₁ to Mn and becomes the state in the solid line B ₄ in the figure. Then, the deflection angle Mn of the boom B ₄ state, also in the case involving the expansion of the boom length L (Ln> Ln- _1), further deflection angle M becomes larger than otherwise.

Naturally, in accordance with these, the tip direction of the boom 3 and the suspending direction of the suspended load 21 (suspending direction vertical line)
The angle formed by and, that is, the hanging load monitoring angle α of the hanging load monitoring camera 15 also changes from αn- ₁ to αn. Therefore, the suspended load monitoring angle .alpha. Naturally needs to be appropriately controlled in consideration of the bending angles Mn- ₁ and Mn of the boom 3 in the above respective states. In addition, in FIG. 11, the suspended load monitoring angle α
Is represented by the angle between the boom tip tangent line d passing through the boom pivot point of the suspended load monitoring camera 15 and the hanging direction vertical line c of the suspended load 21. Further, in the figure, a is a parallel line with the boom no-load line (non-deflecting line) passing through the pivot point, and b is a parallel line with the ground passing through the pivot point.

As the hanging load monitoring angle α, the deflection angle coefficient K data-mapped in the ROM 33 is used with the load W, the boom hoisting angle θ, and the boom length L as parameters on the basis of the preliminary experimental values. Then, it is determined by α = 90 ° −θ (1 + K).

The present embodiment is constructed from the above viewpoints.

Next, FIG. 10 takes into consideration the boom bending angle .alpha., The boom length L, and the boom bending angle .alpha. Which are determined by the hanging load monitoring camera control unit 40 of FIG. The contents of the suspended load monitoring angle control (suspended load tracking control) of the suspended load monitoring camera are shown.

That is, when the control circuit shown in FIG. 9 is turned on, the control operation of the hanging load monitoring camera control unit 40 is started correspondingly to the same as in the case of the above-described embodiment, and first, step S ₁ above boom hoisting angle detection means 2
4. Boom length detecting means 26 and suspended load detecting means 27 detect the present boom hoisting angle θn and boom length L, respectively.
Input n and suspended load W.

Next, in step S ₂ , the current boom hoisting angle θn, boom length Ln, and load W are set using the input current boom hoisting angle detection value θn, boom length Ln, and load W as parameters. Deflection angle coefficient Kn of boom 3 at
Is read from the ROM 33, the monitoring angle αn to be controlled is calculated using the read deflection angle coefficient Kn, and the calculated value αn is calculated in step S ₃ in the random access memory.
The data is stored in the (RAM) 34.

Thereafter, the process proceeds to step S ₄ , and the monitoring angle αn- ₁ calculated in the previous control cycle previously stored in the random access memory 34 is read.

The monitoring angles .alpha.n- ₁ and .alpha.n are calculated as follows in the state of FIG.

[0081] That is, first deflection angle Mn- ₁ in the illustrated boom B ₂ state, the boom hoisting angle Shitaenu- ₁ at that time, the boom length L n _1, load (constant) W deflection is determined as a parameter angle coefficient Kn ₋₁ using Mn− ₁ = θn− ₁ · Kn− ₁
Is required.

The monitoring angle αn− ₁ is αn− ₁ = 90 °.
Since −θn− ₁ + Mn− ₁ , the monitoring angle αn− ₁ that is finally obtained
Considers the same deflection angle _{Mn- 1, αn- 1 = 90 °} -θn- 1
(1 + Kn- ₁ ).

Next, the deflection angle Mn in the state of the boom B ₄ shown in the figure is determined by using the boom hoisting angle θn, the boom length Ln, and the load (constant) W as parameters as the deflection angle coefficient K.
Using n, Mn = θn · Kn.

The monitoring angle αn is αn = 90 ° −θn
Since it is + Mn, the required monitoring angle αn is the same bending angle Mn
In consideration of the above, αn = 90 ° −θn (1 + Kn).

Then, in step S ₅ , it is determined whether or not the current monitoring angle calculation value αn and the previous monitoring angle calculation value αn- ₁ are equal, that is, for example, whether the boom hoisting angle θ is to be increased or decreased. Of the boom length L, and whether or not the suspended load monitoring angle α has changed due to the extension or contraction of the boom length L.

As a result, when YES is determined, that is, from the time of the previous control to this time, there is no change in the hoisting angle θ of the boom 3 and the boom length L itself, and the same boom hoisting angle θ and the same boom length. When only the lifting load 21 itself is lifted under the constant load W of the height L, the bending angle M of the boom 3 is also constant, and the hanging load monitoring camera 15 that is set and controlled by the previous control. Since it is not necessary to change the monitoring angle αn- _{1 of the above} , the control of the relevant cycle is ended as it is.

On the other hand, on the contrary, when the determination in step S ₅ is NO, that is, from the time of the previous control to the time of this control, the boom hoisting angle θ is a predetermined angle in the expanding direction or the contracting direction. When Δθ changes and the boom length L also changes, the flexure angle M of the boom 3 should naturally change, so that the process proceeds to step S ₆ to calculate the current monitoring angle value. Whether αn is larger than the previous monitoring angle calculation value αn− ₁ , that is, is the current monitoring angle αn changed in the expansion direction when viewed from the previous monitoring angle αn− ₁ (FIG. 1).
No. 1 change from B ₂ to B ₄ ) or a change in the shrinking direction (change from B ₄ to B _{2 in} FIG. 11).

As a result, when the determination is YES, that is, when the change is in the monitoring angle expanding direction (B _{2 to} B ₄ ), the process first proceeds to step S ₇ to excite the switching relay 41 to activate the motor drive circuit 36. After switching the first and second relay contacts S ₁ and S ₂ to the motor right rotation side power source polarity, the process proceeds to step S ₈ to expand the current monitoring angle αn from the previous time to the current time. The change angle Δα (Δα = αn−αn− ₁ ) of is calculated.

Then, in the subsequent step S ₁₁ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the clockwise direction of the motor. As a result, the hanging load monitoring camera drive motor 37 rotates clockwise to rotate the hanging load monitoring camera 1
The monitoring angle α of 5 is enlarged and vertically changed so as to coincide with the actual direction of the suspended load 21.

[0090] Further, then proceeds to step S _12, in該監viewing angle enlargement control state, to detect the movement angle Δβ of the actual suspended load monitoring camera 15 based on the output of the potentiometer 38, in step S ₁₃ that follows, The actual detected value Δβ
Is equal to the target drive angle Δα, that is, whether or not the hanging load monitoring camera 15 is actually driven by the target drive angle Δα.

As a result, in the case of NO, that is, when the actual movement angle Δβ is not driven by the target drive angle Δα, the ON control of the power switch 35 in step S ₁₁ is performed.
Detection of Δβ in steps S ₁₂ and S ₁₃ , Δβ = Δα? The judgment control is continued, when it is determined that [Delta] [beta] = [Delta] [alpha] (YES) in step S _13, that is the first time when the monitoring angle of the suspended load monitoring camera 15 is actually driven to the target driving angle (target monitoring angle) [Delta] [alpha] proceeds to step S ₁₄ to stop the driving of the suspended load monitoring camera driving motor 37 to immediately turn OFF the above power switch 35.

As a result, the hanging load monitoring camera 15 accurately reduces the boom hoisting angle θ, and also accurately reduces the boom hoisting angle θ and the flexing angle M by increasing the boom length L. It is rotated in the monitoring angle expanding direction (the direction (b) in FIG. 2) and made to follow the direct downward direction that exactly corresponds to the direction of the suspended load 21, so that the suspended load 21 can be reliably monitored.

On the other hand, as a result of the suspended load monitoring angle comparison determination in consideration of the present and previous boom deflection angles in step S ₆ , N
When the monitoring angle α is determined to be O (B _{4 to} B ₂ ), that is, when the boom hoisting angle θ is increased and the boom length L is changed in the reduction direction, the process proceeds to step S ₉ and the switching is performed. Relay 4
1 is activated to switch the first and second relay contacts S ₁ and S ₂ of the motor drive circuit 36 to the motor left rotation side power source polarity, and then the process proceeds to step S ₁₀ and the current monitoring angle is concerned. Angle of change Δn from the previous time to the current time Δn (αα
= Αn− ₁₋ αn) is calculated.

Then, in the subsequent step S ₁₁ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the motor left rotation direction for reducing the monitoring angle. As a result, the above-mentioned suspended load monitoring camera drive motor 37 rotates counterclockwise and the monitoring angle of the suspended load monitoring camera 15 is reduced, and the actual suspended load 2
It is changed to match the direction of 1.

[0095] Further, the process proceeds to step S _12, in該監viewing angle reduction control state, the detected movement angle Δβ of the actual suspended load monitoring camera 15 outputs based on the potentiometer 38, in step S ₁₃ that follows, when said actual Whether the detection value Δβ becomes equal to the target drive angle Δα, that is, whether the hanging load monitoring camera 15 is actually driven by the target drive angle Δα in the reduction direction.

As a result, in the case of NO, that is, when the actual drive angle Δβ has not been driven by the target drive angle Δα, ON control of the power switch 35 in step S ₁₁ is performed.
Detection of Δβ in steps S ₁₂ and S ₁₃ , Δβ = Δα? When the determination control of step S ₁₄ is continued and Δβ = Δα (YES) is determined in step S ₁₃ , that is, the suspended load monitoring camera 15 is actually driven to the target drive angle (target monitoring angle) Δα, step S _{14 is performed.} Then, the power switch 35 is immediately turned off to stop driving the hanging load monitoring camera drive motor 37.

As a result, in addition to the expansion of the boom hoisting angle θ, the hanging load monitoring camera 15 accurately monitors the inside in response to the expansion of the boom hoisting angle θ and the reduction of the boom bending angle due to the reduction of the boom length L. It is rotated in the angle reduction direction (the direction (a) in FIG. 2) and is made to follow the direct downward direction that exactly corresponds to the direction of the suspended load 21, and it is possible to appropriately monitor the suspended load 21.

Then, the control is repeated at a predetermined cycle.

In the above embodiments, since the crane adopting the telescopic boom is premised, the amount of flexure is taken into consideration with the boom length as a parameter. For example, in the case of the non-telescopic boom, Needless to say, it is sufficient to configure so as to consider the amount of bending only from the boom hoisting angle and the load.

In the above description, in addition to the boom hoisting angle θ, when the suspended load monitoring angle α is variably controlled in consideration of the boom bending angle M determined by the boom length and load, first, the suspended load monitoring camera is driven. The motor 37 is driven, and when the moving angle Δβ actually detected by the potentiometer 38 becomes equal to the target drive angle Δα, the suspended load monitoring camera drive motor 37 is stopped. As another method, the variable control of the monitoring angle may include, for example, the hanging load monitoring camera drive motor 3 corresponding to the target driving angle Δα.
It goes without saying that the driving time of 7 may be set, and when the driving time elapses, the power supply of the hanging load monitoring camera drive motor 37 may be turned off and stopped.

(Embodiment 3) Next, FIGS. 12 to 15 show the construction of a suspended load monitoring device for a crane according to Embodiment 3 of the present invention.

In the structure of this embodiment, for example, as shown in FIG. 12, the same suspended load monitoring camera 15 as that of the above-described first embodiment is provided at the tip of a boom other than the top boom, for example, the tip side of the base boom 3a, and FIG. As shown in FIG.
The extension length L of the boom 3 is further added to the configuration of the control circuit of the first embodiment including the boom hoisting angle detecting means 24 shown in FIG.
Boom length detecting means 26 for detecting the wire length and wire feeding length detecting means 28 for detecting the wire feeding length A of the wire 11 from the winch 7 are respectively added, and the detection signals of the respective detecting means 24, 26, 28 are added. The suspended load monitoring camera control unit 40 is A / D converted through the A / D converter 25.
Based on the three detection parameters of the boom hoisting angle θ, the boom length L, and the wire feeding length A, It is characterized in that the hook 13 and the suspended load 21 can be always accurately monitored by performing more appropriate elevation angle control of the suspended load monitoring camera 15 in consideration of changes.

Next, FIG. 14 shows a boom hoisting angle, a boom length, and a boom length by the suspended load monitoring camera control unit 40 of FIG.
The contents of the suspended load monitoring angle control (suspended load tracking control) of the suspended load monitoring camera according to changes in the suspended load position are shown.

In the following description of this embodiment, since the mounting position of the suspended load monitoring camera attached to the boom is different from those in the above two examples, the monitored angle of the suspended load monitoring camera is particularly expressed as an elevation angle. I will decide.

That is, when the control circuit of FIG. 13 is turned on, the control operation of the hanging load monitoring camera control unit 40 is started correspondingly, and first, at step S ₁ , the boom hoisting angle detecting means 24 is operated. , Boom length detection means 2
6. Current boom hoisting angle θn, boom length Ln, wire payout length A detected by the wire payout length detecting means 28, respectively.
Enter n.

Then, in step S ₂ , the corresponding camera elevation angle (control target angle) φn is calculated based on the input current boom hoisting angle θn, boom length Ln, and wire feeding length An. Then, in step S ₃ , the calculated value φn is stored in the random access memory (RAM) 34.

The camera elevation angle φ (φn, φn− ₁ ) is φ = (1
80 ° -θ) -tan- ¹ [{(L-Lo) sin θ-A} / {(L-L
o) cos θ}]. Lo is the base boom 3a
Is the length from the base end (supporting point) to the mounting position of the suspended load monitoring camera 15.

Thereafter, the process proceeds to step S ₄ , and the camera elevation angle φ detected in the previous control cycle previously stored in the random access memory (RAM) 34 is detected.
Read n- ₁ .

Then, in step S ₅ , whether or not the current camera elevation angle φn and the previous camera elevation angle φn- ₁ are equal, that is, the boom undulation angle θ is changed in either the enlargement direction or the reduction direction, the boom 3 It was determined whether or not the expansion / contraction of the wire, the extension of the wire 11, and the pull-in were performed.

As a result, when YES is determined, that is, from the time of the previous control to this time, there is no change in the hoisting angle θ of the boom 3, the boom length L, and the wire payout length A, and the same hoisting angle of the boom, When the boom length is the same and the wire extension length is the same, it is not necessary to change the elevation angle (monitoring direction) of the suspended load monitoring camera 15 that has been set and controlled in the previous control, so the control of the relevant cycle is ended as it is. .

On the other hand, on the contrary, when the determination in step S ₅ is NO, that is, the boom hoisting angle changes by a predetermined angle in the expanding direction or the contracting direction from the previous control to the current control. and it is changed or boom length, when the winch is driven, subsequently the process proceeds to step S _6,
It is determined whether or not the calculated current camera elevation angle φn is larger than the previous camera elevation angle φn- ₁ .

As a result, when it is determined to be YES, the control in the direction of increasing the elevation angle is required. First, the process proceeds to step S ₇ to excite the switching relay 41 to activate the first and second motor drive circuits 36. After switching the relay contacts S ₁ and S ₂ of _{No. 2} to the polarity of the power supply on the right side of the motor rotation, the process further proceeds to step S ₈ and the change angle Δφ ₁ (Δφ _{1 of the} current camera elevation angle φn in the enlargement direction from the previous time). = Φn-φn- ₁ ) is calculated.

Then, in the subsequent step S ₁₁ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the clockwise direction of the motor. As a result, the hanging load monitoring camera drive motor 37 rotates clockwise to rotate the hanging load monitoring camera 1
The elevation angle (monitoring direction) of 5 is the actual hook 13 or the suspended load 21.
Is changed to match the direction of.

Further, in step S ₁₂ , in the elevation angle (monitoring direction) variable control state, based on the output of the potentiometer 38, the actual movement angle Δ of the suspended load monitoring camera 15 is determined.
φ ₂ is detected, and in the subsequent step S ₁₃ , whether or not the actual detection value Δφ ₂ becomes equal to the target drive angle Δφ ₁ , that is, the hanging load monitoring camera 15 actually determines the target drive angle Δφ _2.
It determines whether or not driven by phi _1.

As a result, in the case of NO, that is, when the actual movement angle Δφ ₂ is not yet driven by the target drive angle Δφ ₁ , ON control of the power switch 35 in step S ₁₁ above, steps S ₁₂ and S ₁₃ Of Δφ ₂ of Δφ ₂ = Δφ ₁ ?
The judgment control is continued, Δφ ₂ = Δφ ₁ at step S ₁₃ (Y
ES), that is, when the suspended load monitoring camera 15 is actually driven to the target drive angle (target monitored angle) Δφ ₁ , the process proceeds to step S ₁₄ and the power switch 35 is immediately turned off to suspend the suspended load. The drive of the surveillance camera drive motor 37 is stopped.

As a result, the suspended load monitoring camera 15 is accurately rotated in the direction of increasing the elevation angle in response to, for example, the boom hoisting angle θ being reduced, the boom length being extended, and the wire 11 being pulled in. 21 is made to follow the direction that exactly corresponds to the direction of 21, and the appropriate hook 13 and suspended load 2
1 can be monitored.

On the other hand, when it is determined as NO as a result of the comparison between the present and previous camera elevation angle calculation values in step S _6, it is necessary to perform control in the elevation angle reduction direction first.
_After proceeding to step ₉ to excite the switching relay 41 to switch the first and second relay contacts S ₁ and S ₂ of the motor drive circuit 36 to the motor left rotation side power source polarity, further step S ₁₀
Then, the change angle Δφ ₁ (Δφ ₁ = φn− ₁₋ φn) of the current camera elevation angle φn in the reduction direction from the previous time is calculated.

Then, in the subsequent step S ₁₁ , the power switch 35 is turned on to supply power to the motor drive circuit 36 in the leftward rotation direction of the motor. As a result, the hanging load monitoring camera drive motor 37 rotates counterclockwise and the hanging load monitoring camera 1
The monitoring direction of 5 is changed so as to match the actual direction of the hook 13 or the suspended load 21.

Further, in step S ₁₂ , the actual movement angle Δφ ₂ of the suspended load monitoring camera 15 is detected based on the output of the potentiometer 38 in the monitoring direction variable control state, and in the subsequent step S ₁₃ , Actual detected value Δφ
_It is determined whether ₂ is equal to the target drive angle Δφ ₁ , that is, whether the hanging load monitoring camera 15 is actually driven by the target drive angle Δφ ₁ .

As a result, in the case of NO, that is, when the actual movement angle Δφ ₂ is not yet driven by the target drive angle Δφ ₁ , ON control of the power switch 35 in step S ₁₁ above, steps S ₁₂ and S ₁₃ Of Δφ ₂ of Δφ ₂ = Δφ ₁ ?
The judgment control is continued, Δφ ₂ = Δφ ₁ at step S ₁₃ (Y
ES), that is, when the suspended load monitoring camera 15 is actually driven to the target drive angle (target elevation angle) Δφ ₁ , the process proceeds to step S ₁₄ and the power switch 35 is immediately turned off.
The driving force of the hanging load monitoring camera drive motor 37 is stopped at F.

As a result, the hanging load monitoring camera 15 is accurately rotated in the direction of decreasing the elevation angle in response to an increase in the boom hoisting angle θ, a contraction of the boom length, and the feeding of the wire 11. 21 is made to follow the direction that exactly corresponds to the direction of 21, and the appropriate hook 13 and suspended load 2
1 can be monitored. The control is repeated in a predetermined cycle.

In the above description, the boom hoisting angle θ,
When variably controlling only the elevation angle (monitoring angle) of the suspended load monitoring camera in response to changes in the boom length L and wire extension length,
First, the hanging load monitoring camera drive motor 37 is driven, and the hanging load monitoring camera drive motor 37 is stopped when the movement angle actually detected by the potentiometer 38 becomes equal to the target monitoring angle. As another method, the variable control of the elevation angle of the suspended load monitoring camera may be performed by setting a driving time of the suspended load monitoring camera drive motor 37 corresponding to the monitoring angle and driving the suspended load monitoring camera when the drive time elapses. It goes without saying that the motor 37 may be turned off and stopped.

(Embodiment 4) Even when the suspended load monitoring camera 15 is attached to the tip end portion of the base boom 3a as in the configuration of the suspended load monitoring device for a crane of the above-described Example 3, the above-described implementation is carried out. The same bending of the boom 3 as in the case of Example 2 occurs. Therefore, in the case of the third embodiment, as in the case of the second embodiment, the boom hoisting angle θn, the boom length Ln, and the load W of the suspended load are detected to calculate the bending angle of the boom. The elevation angle φn of the suspended load monitoring camera 15 may be controlled in consideration of the change of

The control similar to that of this embodiment is applied to the case other than the above, for example, when the suspended load monitoring camera 15 is provided on the tip side of the top boom 3d as in the case of the above-described first embodiment. The same can be applied to the case where a boom is added to the tip of 3d to provide work.

(Fifth Embodiment) By the way, in the case of the above-mentioned first and second embodiments, the hook 13 and the suspended load 21 are moved up and down corresponding to the change in the payout length A of the wire 11, and the extension amount L of the boom 3 is large or small. Due to the change in the payout length A of the wire 11 in relation to the change, the distance between the hanging load monitoring camera 15 and the hook 13 and the hanging load 21 changes considerably, and the focal length changes. Therefore, in this case, according to the control of the monitoring direction,
An autofocus control for variably adjusting the focal length according to, for example, the payout length A of the wire 11 is also adopted as necessary.

This problem is exactly the same in the case of the third embodiment, for example, and in the case of the third embodiment, as shown in FIG. 15, for example, the hoisting angle θ of the boom 3, the extension amount L and the feeding length of the wire 11 are as shown in FIG. The change in A changes the focal length M.

Therefore, in the case of the third embodiment, a control system for automatically adjusting the focal length by performing the autofocus control with the boom hoisting angle θ, the boom length L, and the wire payout length A as parameters is also used as needed. Adopted.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration of an entire crane in a crane load monitoring device according to a first embodiment of the present invention.

FIG. 2 is an enlarged view showing a state where a suspended load monitoring camera is attached to a boom tip portion of the crane.

FIG. 3 is a skeleton diagram of essential parts showing a configuration of a boom tip portion of the crane.

FIG. 4 is a front view of a monitor television provided in the cab of the crane.

FIG. 5 is a block diagram showing a configuration of a control circuit unit of the hanging load monitoring device.

FIG. 6 is a flowchart showing control contents of the hanging load monitoring device.

FIG. 7 is an operation explanatory view when the boom hoisting angle is enlarged corresponding to the control content of FIG. 6;

FIG. 8 is an operation explanatory view when the boom hoisting angle is reduced corresponding to the control content of FIG. 6;

FIG. 9 is a block diagram showing a configuration of a control circuit unit of a crane hanging load monitoring device according to a second embodiment of the present invention.

FIG. 10 is a flowchart showing the control contents of the device.

FIG. 11 is an operation explanatory diagram corresponding to the control content of FIG. 10;

FIG. 12 is a diagram showing a configuration of an entire crane in a crane suspended load monitoring device according to a third embodiment of the present invention.

FIG. 13 is a block diagram showing a configuration of a control circuit unit of the hanging load monitoring device.

FIG. 14 is a flowchart showing the control contents of the device.

FIG. 15 is an operation explanatory diagram corresponding to the control content of FIG. 14;

FIG. 16 is a diagram showing a crane working state of a conventional general mobile crane.

[Explanation of symbols]

1 is a vehicle, 2 is a swivel, 3 is a boom, 7 is a winch, 1
1 is a wire, 12 is a boom head, 13 is a hook, 1
5 is a suspended load monitoring camera, 20 is a monitor TV, 24 is a boom hoisting angle detection means, 26 is a boom length detection means, 27
Is a load detecting means, 28 is a wire feeding length detecting means, 35
Is a power switch, 36 is a motor drive circuit, 37 is a suspended load monitoring camera drive motor, 38 is a potentiometer, 40 is a suspended load monitoring camera control unit, and 41 is a switching relay.

Claims (6)

[Claims] 1. A base, a revolving base rotatably provided on the base, a boom supported by the revolving base so as to be up and down and extendable, and a winch provided on the revolving base.
A wire extending from the winch along the boom and vertically extending downward from the tip side of the top boom, a sling hook provided at the lower end of the wire, and a top boom tip of the boom. The hung load monitoring camera rotatably mounted on the pedestal, the monitor TV installed in the driver's seat on the base side that displays the image of the hung load monitoring camera, and the hung load monitoring camera is rotated in the hanging direction. In a crane comprising a suspended load monitoring camera driving unit that is dynamically driven, the suspended load monitoring camera constantly monitors the suspended load corresponding to a boom state detection unit that detects a boom state and a detected value of the boom state detection unit. And a drive amount control means for controlling the drive amount of the above-mentioned suspended load monitoring camera drive means so as to follow the above. 2. The boom state detection means comprises a boom hoisting angle detection means, and the drive amount control means corresponds to the boom hoisting angle detected by the boom hoisting angle detection means and the driving amount of the suspended load monitoring camera drive means. The suspended load monitoring device for a crane according to claim 1, wherein 3. The boom state detecting means comprises a boom hoisting angle detecting means and a load detecting means, and the drive amount controlling means detects the boom hoisting angle and the hanging load detected by the boom hoisting angle detecting means and the load detecting means. 2. The hanging load monitoring device for a crane according to claim 1, wherein the driving amount of the hanging load monitoring camera driving means is controlled in consideration of the amount of bending of the boom determined by the load. 4. The boom state detecting means includes a boom hoisting angle detecting means, a boom length detecting means, and a load detecting means.
The drive amount control means is configured to detect the hoisting load in consideration of the boom hoisting angle detection means, the boom length detection means, the boom hoisting angle detected by the load detection means, the boom length, and the bending amount of the boom determined by the hoisting load. The suspended load monitoring device for a crane according to claim 1, wherein the drive amount of the monitoring camera driving means is controlled. 5. A base, a revolving base rotatably provided on the base, a boom supported by the revolving base so as to be up and down and extendable, and a winch provided on the revolving base.
A wire extending from the winch along the boom and vertically extending downward from the tip side of the top boom, a sling hook provided at the lower end of the wire, and a boom other than the top boom. A suspended load monitoring camera rotatably provided at the tip, and a monitor TV provided in the driver's seat on the base side showing an image of the suspended load monitoring camera,
In a crane comprising a suspended load monitoring camera driving means for rotationally driving the suspended load monitoring camera in the suspended direction, a boom state detecting means for detecting a boom state, and a detection value of the boom state detecting means. And a drive amount control means for controlling the drive amount of the suspended load monitoring camera driving means so that the suspended load monitoring camera always follows the suspended load. 6. The boom state detecting means comprises a boom hoisting angle detecting means, a boom length detecting means and a wire feeding length detecting means, and the drive amount controlling means comprises the boom hoisting angle detecting means,
In order to control the drive amount of the suspended load monitoring camera drive means in accordance with the suspended load position determined by the boom length detection means, the boom hoisting angle detected by the wire payout length detection means, the boom length, and the wire payout length. The suspended load monitoring device for a crane according to claim 5, wherein: