JPH01209224A - Boom protector for mechanical type continuous unloader - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a boom protection device for a mechanical continuous unloader, and in particular, the present invention relates to a boom protection device for a mechanical continuous unloader. The present invention relates to a protection device that limits the torsional moment that is applied to a horizontal boom by reducing the hydraulic pressure of a swing hydraulic motor when a horizontal boom is applied.

[Conventional technology]

In general, a mechanical continuous unloader is equipped with a vertical conveyor that vertically unloads bulk materials from a ship's hold, and a horizontal conveyor that subsequently transports the bulk materials toward land.These vertical conveyors and horizontal conveyors are operated by separate booms. It is mounted on a frame so that it can rotate while being supported.

As shown in Fig. 2, the vertical boom 1 supporting the vertical conveyor is a swing cylinder 2, and the horizontal boom 3 supporting the horizontal conveyor is a luffing cylinder 4 with a swing angle θ9.
, the undulation angle θ8 can be changed. Furthermore, the frame 5 on which these booms 1.3 are mounted is equipped with a swing gear 6 and a swing hydraulic motor, so that the vertical boom 1, the horizontal boom 3, the balance weight 8, etc. can swing as a whole.

[Problem to be solved by the invention]

By the way, in such a configuration, if the ship rocks while the feeder 9 at the lower end of the vertical conveyor is buried in bulk materials (not shown) and unloaded, the feeder 9 will be removed from the bulk material. You will receive power. When the direction of this force acts like the force F shown in FIG. 3, the hydraulic pressure of the hydraulic motor 7 is IJ
IJ-F, the horizontal boom 3 rotates in the direction of the force F, and a mechanism for protecting the boom is activated. In this case, IJ
Since the IJ-voltage is set to a constant value and used, this method acts to limit the value of the moment (Ms) centered on the swing gear 6.

However, in this case, the most dangerous stress is the stress due to the torsional moment MH of the horizontal boom 3, but the moments M3 and MH do not match as shown in equations (1) and (2) below, and θ
, are varied from -30° to +30°, and θ8 is varied from -20° to +20°, the relationship between the moment Ms and MM is widely distributed as shown in FIG.

MS=Fx (Lv Xs inθV+L)ICO3θ
, )...(1) M, = FXLv xCO6(θ, -θH)...
(2) Therefore, the conventional method of relieving hydraulic pressure at a constant pressure has the problem that protection against the most important twisting of the horizontal boom 3 is insufficient.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problem and provide a boom protection device for a mechanical continuous unloader that can prevent the torsional moment of the horizontal boom from exceeding a set value regardless of the values of the swing angle and the heave angle. .

[Means to solve the problem]

The present invention supports a vertical conveyor and a horizontal conveyor with a vertical boom and a horizontal boom, respectively, swings the vertical boom and raises and lowers the horizontal boom with a hydraulic cylinder, and turns the vertical boom and the horizontal boom with a hydraulic motor. In a mechanical continuous unloader configured as shown in FIG. The structure includes a solenoid valve that relieves hydraulic pressure.

[Effect]

As described above, the present invention detects the angle between the vertical boom and the vertical in the projection plane from one end of the horizontal boom, and uses this value to relieve the hydraulic pressure of the swing hydraulic motor, so that the swing angle can be adjusted. It is possible to keep the torsional moment applied to the horizontal boom within the permissible value, regardless of the value of the boom and the heave angle.

〔Example〕

Hereinafter, the present invention will be described in detail using figures showing examples.

FIG. 1 is a control system diagram showing an embodiment of a boom protection device for a mechanical continuous unloader according to the present invention. The vertical conveyor and the horizontal conveyor are supported by a vertical boom 10 and a horizontal boom 11, respectively, and these vertical booms 10,
The horizontal boom 11 is rotated by a hydraulic motor 12.

Reference numeral 13 denotes a control panel, and the control panel 13 includes an angle sensor 15 that detects the angle formed by the vertical boom 10 and the vertical direction 14 in the projection plane of the vertical boom 10 from one end surface direction of the horizontal boom 11. Solenoid valve 16 that opens and closes with a voltage signal
is connected. The electromagnetic valve 16 is installed branching off from the hydraulic piping F, 18 of the hydraulic motor 12, and has a structure including a throttle valve 19 and check valves 20 to 23 at the front and rear. In FIG. 1, reference numeral 24 indicates a vertical conveyor or a feeder disposed at the lower end, 25 indicates a swing gear, and 26
indicates a tank.

In such a configuration, when the feeder 24 receives a force F (force F), a torsion moment as shown in the above equation (2) acts on the horizontal boom 11.

At this time, the vertical boom 10 makes an angle θ, S with the vertical direction 14 on a projection plane from one end of the horizontal boom 11. For nuclear θ7. is determined by the torsional moment M8 of the horizontal boom 11 regardless of the angle θ9 or the angle θ□ (see FIG. 2), so the torsional moment MW is determined by the angle θ9. It can be found by

On the other hand, if the value of the angle sensor 15 exceeds the allowable value, the solenoid valve 16 is opened by the output signal from the control panel 13. When the solenoid valve 16 is opened, oil flows from the high pressure side to the low pressure side or to the tank 26 side, regardless of which of the hydraulic lines 17, 18. In this way, the oil on the high pressure side leaks out,
The horizontal boom 11 turns in the opposite direction to the direction in which the force F acts, that is, the horizontal boom 11 follows the force F.

Thereby, it is possible to avoid applying a torsional moment exceeding a certain level to the horizontal boom 11, and it is possible to safely protect the horizontal boom 11. However, the protection device described above should be activated only during unloading, and does not need to be activated in other situations, such as when changing the position of the feeder 24.

Furthermore, if the structure is such that a solenoid valve 27 is provided in series with the solenoid valve 16 as shown in FIG. 1, the operating state of the protection device of the present invention can be limited. That is, by detecting that the unloader is unloading using the load power of the feeder 24 and opening the solenoid valve 27 only when this is detected, the operating time of the device of the present invention can be limited to the necessary minimum. can.

In addition, in the above-mentioned embodiment, the case where a hydraulic motor was used as the turning motor was described. However, the invention is not limited to this, and if an electric motor is used, the same effect can be obtained by opening and closing the attached brake or clutch according to the value of the angle sensor. .

〔Effect of the invention〕

As explained above, the present invention supports a vertical conveyor and a horizontal conveyor with a vertical boom and a horizontal boom, respectively, swings the vertical boom and raises and lowers the horizontal boom with a hydraulic cylinder, and rotates the vertical boom and the horizontal boom. In a mechanical continuous unloader configured to be operated by a hydraulic motor, an angle sensor is installed to detect the angle between the vertical boom and the vertical in the projection plane of the vertical boom from one end of the horizontal boom, and based on the output of the sensor, We installed a solenoid valve that reefs the hydraulic pressure of the swing hydraulic motor to maintain the angle between the vertical boom and the vertical below a certain value, so regardless of the swing angle or luffing angle, torsion applied to the horizontal boom is reduced. This has the effect that the moment can be kept within the permissible value.

[Brief Description of the Drawings] Fig. 1 is a control system diagram showing an embodiment of a boom protection device for a mechanical continuous unloader according to the present invention, and Fig. 2 is a schematic configuration diagram showing an example of a conventional mechanical continuous unloader. , FIG. 3 is a front view of FIG. 2 when viewed from the direction of line A-A, and FIG. 4 is a diagram for explaining the problems of the prior art. 10... Vertical boom, 11... Horizontal boom, 12... Hydraulic motor, 15... Angle sensor, 16.27... Solenoid valve. Figure 4 A1 Koya Middle 1W hair - Nunto Ms

Claims (2)

[Claims] (1) The vertical and horizontal conveyors are supported by vertical booms and horizontal booms, respectively, the swing of the vertical boom and the raising and lowering of the horizontal boom are performed by hydraulic cylinders, and the rotation of these vertical and horizontal booms is performed by hydraulic motors. In the constructed mechanical continuous unloader, an angle sensor is installed to detect the angle between the vertical boom and the vertical in the projection plane of the vertical boom from one end of the horizontal boom, and the output of the sensor determines the hydraulic pressure of the swing hydraulic motor. A boom protection device for a mechanical continuous unloader, characterized by being equipped with a solenoid valve that relieves. (2) The boom protection device for a mechanical continuous unloader as set forth in claim (1), further comprising a solenoid valve that opens and closes depending on the load of the feeder in series with the solenoid valve.