JPH0735901Y2 - Safety device for digging column car - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a safety device for a digging column truck.

(Prior Art) As shown in FIG. 4, a conventional digging column truck has a telescopic boom 1 at the tip of a telescopic boom 1 which is mounted on a vehicle A so that it can be undulated and is undulated by a hydraulic cylinder 2 for undulation driving. An auger drill 3 which can be rotationally driven is suspended, and the telescopic boom is driven to fall down to press the auger drill 3 against the ground, and the auger drill 3 is rotationally driven to form a hole in the ground. The telescopic boom 1 is composed of a base boom 4 and a front boom 5, and the front boom 5 is inserted into the base boom 4 and an appropriate drive means (for example, a hydraulic cylinder or the like) is provided between them.
Is arranged so that the front boom 5 can be expanded and contracted from the base boom 4. Therefore, the front boom 5 is extended from the base boom 4, the auger drill 3 hung at the tip of the front boom 5 is positioned farther than the position where the vehicle A is installed, and a hole is drilled in the ground located at this distance. I am able to do that.

(Problems to be solved by the invention) By the way, when drilling a hole in the ground by using this type of digging column, when the auger drill 3 is rotated in the reverse direction, due to the soil quality of the ground, the auger drill 3's own driving force causes The telescopic boom 1 may be pushed up. Due to this lifting force, an excessive force is applied to the telescopic boom 1 to deform the telescopic boom 1 and the like, and one side of the vehicle A is levitated, and the stability of the vehicle A is impaired.

In the present invention, when the auger drill 3 is rotated in the reverse direction when a hole is drilled in the ground by a boring wheel, the force for pushing up the telescopic boom generated by the propulsive force of the auger drill 3 itself is used for undulating drive. An object of the present invention is to provide a digging column vehicle which detects a load acting on a hydraulic cylinder for a vehicle and limits rotational drive of an auger drill.

(Means for Solving the Problems) In order to achieve the above object, the safety device for a digging column vehicle of the present invention is an extension / contraction system that is mounted on a vehicle so that it can be lifted and lowered by a hydraulic cylinder for driving the lift. An auger drill that can be driven to rotate is hung at the tip of the boom, and the telescopic boom is tilted to press the auger drill against the ground and the auger drill is driven to rotate to form a hole in the ground. Which is a safety device for a digging column vehicle, wherein when the auger drill is used to drill a hole in the ground, when the auger drill is rotated in the reverse direction, the pulling force for pushing up the telescopic boom generated by the propulsive force of the auger drill itself. Is a drooping force detector for detecting by detecting a load acting on the undulation driving hydraulic cylinder, a boom length detector for detecting the telescopic boom length of the telescopic boom, A limit value output means for receiving a boom length signal from the boom length detector and outputting a limit value as a function of the boom length of the telescopic boom, and a limit value signal from the limit value output means and the drooping force detector. Comprising a comparison means for receiving a signal and outputting an auger drill rotation drive restriction signal when the latter signal is lower than the former signal, and an alarm means or an auger drill rotation drive restriction means activated by the auger drill rotation drive restriction signal from the comparison means. It is characterized by having done.

(Operation) In the safety device for a digger / columner of the present invention having the above-described structure, when the telescopic boom is pushed up, the load acting on the undulating drive hydraulic cylinder decreases, and an alarm means is provided. Is activated to alert the operator, or the auger drill rotation drive limiting means is activated to automatically limit the rotation drive of the auger drill. Therefore, when drilling a hole in the ground, even if the auger drill is rotated in the reverse direction, the propelling force of the auger drill itself does not cause the telescopic boom to push up, and excessive force is applied to the telescopic boom. It is possible to prevent accidents such as deforming the telescopic boom or the like, or causing one side of the vehicle to float and impairing the stability of the vehicle.

(Embodiment) An embodiment of the safety device for a digging column vehicle of the present invention will be described based on FIGS. 1 to 3. In FIG. 1, reference numerals 1 to 5 are the same as those shown in FIG. 4 and described in the related art, and therefore the description thereof is omitted.

In FIG. 1 and FIG. 2, 6 detects the load acting on the undulation driving hydraulic cylinder 2 to detect the lift force for pushing up the telescopic boom 1 by the propulsive force of the auger drill 3 itself. A pressure sensor for measuring the pressure of the load cell 6a (force-electric signal converter) interposed in the piston rod or the bracket portion of the hydraulic cylinder 2 or the pressure in the extension operation side pressure oil chamber of the hydraulic cylinder 2. It is composed of a transducer 6b (pressure-electric signal converter). Reference numeral 7 denotes a telescopic boom length detector for detecting the telescopic boom length of the telescopic boom 1. The tip of the cord fed out from the cord winder attached to the base boom 4 is fixed to the tip of the boom 5, and the base boom is attached. When the boom 5 ahead of 4 is expanded and contracted, the cord take-up amount by the cord take-up device is configured to detect the telescopic boom length using a potentiometer. Numeral 8 is a limit value output means for receiving a telescopic boom length signal from the telescopic boom length detector 7 and outputting a limit value Fmax described later as a function of the telescopic boom length l. Reference numeral 9 receives a limit value signal Fmax from the limit value output means and a signal F from the lift force detector 6, and outputs an auger drill rotation drive regulation signal L when the latter signal F is lower than the former signal Fmax. It is a means. Reference numeral 10 is an alarm means which is activated by the auger drill rotation drive restriction signal L of the comparison means 9,
11 and the alarm lamp 12 or any one of them.

When the auger drill 3 is hung at the tip of the telescopic boom 1, the limit value output means 8 is used to lift and lower the hydraulic cylinder 2.
The detection value of the load acting on the retractable boom force detector 6 is output as a function of the telescopic boom length l. Specifically, it is composed of a digital memory that uses the telescopic boom length signal as an index signal. The limit value is set as a function of the telescopic boom length 1 because the load acting on the undulation drive hydraulic cylinder 2 detected by the lift force detector 6 changes as the telescopic boom length 1 changes. . It should be noted that the limit value output means 8 in the above-mentioned embodiment only needs to hoist the telescopic boom 1 by the length of the auger drill 3 during the drilling work with the auger drill 3, and the hoisting angle of the telescopic boom 1 is used within a relatively narrow range. Therefore, the function of the hoisting angle of the telescopic boom 1 is omitted and is output only as a function of the telescopic boom length 1. However, when using a long auger drill, or when outputting the limit value accurately, the telescopic boom hoisting angle detector 13 that detects the hoisting angle of the telescopic boom 1 is provided. The hoisting angle signal θ from the detector is input to the limit value output means 8, and the limit value output means 8 is also used to set the telescopic boom length l.
And a limit value signal as a function of the telescopic boom hoisting angle θ may be output.

The safety device for a digging column vehicle constructed in this way operates as follows. When drilling a hole in the ground, when the auger drill 3 is rotated in the reverse direction and the propulsive force of the auger drill 3 approaches the state where the telescopic boom 1 is pushed up,
Since the signal F from the rod force detector 6 is smaller than Fmax output by the limit value output means 8, the comparison means 9 issues the auger drill rotation drive restriction signal L. As a result, warning means 10
Is activated to inform the operator that the telescopic boom 1 is pushed up by the reverse rotation of the auger drill 3. Therefore, it is possible to prevent an accident such as an excessive force being applied to the telescopic boom 1 to deform the telescopic boom 1 or the like, or one side of the vehicle A being levitated to impair the stability of the vehicle A.

In the above embodiment, the warning means 10 is activated by the auger drill rotation drive regulation signal L issued by the comparison means 9, but as shown in FIG. Needless to say, the auger drill rotation drive limiting means 14 for automatically limiting the rotation drive of the auger drill 3 may be operated. That is, as shown in FIG.
The auger drill rotation drive restricting means (unload valve) 14 attached to the rotation drive hydraulic circuit of the auger drill 3 may be operated via a switch connected by the auger drill rotation drive restriction signal L. Although the auger drill rotation drive limiting means 14 shown in FIG. 3 is composed of an unload valve, it may be configured to connect the low pressure circuit and the high pressure circuit of the hydraulic motor that drives the auger drill 3 to rotate.

Next, the limit value output means 8 of the above-described embodiment detects the load acting on the undulation driving hydraulic cylinder 2 by the lift-up force detector 6 when the auger drill 3 is suspended at the tip of the telescopic boom 1. Although the detection value of the telescopic boom 1 is set to the limit value, it is only necessary to be able to determine the state in which the lift force for pushing up the telescopic boom 1 by the auger drill 3 acts on the telescopic boom 1. The load acting on the undulation driving hydraulic cylinder 2 when the auger drill is not suspended at the tip (the load due to the own weight of only the telescopic boom 1) is set as the detection value detected by the rod-up detector 6 as a limit value. Is also good.

(Effect of the Invention) Since the present invention is configured and operates as described above,
When drilling a hole in the ground, the auger drill does not reversely rotate and the propelling force of the auger drill itself pushes up the telescopic boom. It is possible to prevent accidents such as deformation of the vehicle and floating of one side of the vehicle to impair the stability of the vehicle.

[Brief description of drawings]

1 and 2 are explanatory views of a safety device for a digging column vehicle according to the present invention, and FIG. 3 is an explanatory view of another embodiment of a safety device for a digging column vehicle according to the present invention. , FIG. 4 is an explanatory view of a conventional boring column car. A: Vehicle, 1: Telescopic boom, 2: Hydraulic cylinder, 3: Auger drill, 6: Lifting force detector, 7: Telescopic boom length detector, 8: Limit value output means, 9: Comparison means, 10: Alarm Means, 14: Auger drill rotation drive limiting means

Claims (1)

[Scope of utility model registration request] 1. An auger drill, which is rotatably mounted on a vehicle and is rotatably driven by a hydraulic cylinder for driving undulation, hangs a freely rotatable auger drill at the tip of the telescopic boom, and drives the telescopic boom to fall and descend to drive the auger drill. Is a safety device for a digging column vehicle, which is configured to punch a hole in the ground by rotating the auger drill while pressing the auger drill. When the drill is rotated in the reverse direction, the lift force that pushes up the telescopic boom generated by the propulsive force of the auger drill itself is detected by detecting the load acting on the undulation drive hydraulic cylinder. And a boom length detector for detecting the telescopic boom length of the telescopic boom, receiving a boom length signal from the boom length detector as a function of the boom length of the telescopic boom. Limit value output means for outputting a limit value,
Comparing means for receiving the limiting value signal from the limiting value output means and the signal from the plunge force detector and outputting an auger drill rotation drive regulation signal when the latter signal is smaller than the former signal, and an auger from the comparing means. A safety device for a digging column vehicle, comprising alarm means which is activated by a drill rotation drive restriction signal or auger drill rotation drive restriction means.