JPH0630899Y2 - Hydraulic cylinder speed adjusting device for root consolidation in medium excavation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a hydraulic cylinder speed adjusting device for root consolidation in a medium excavation method.

(Prior art) As a method of constructing foundation piles on the ground, an August cruc is inserted into the hollow pile, the ground is excavated by this August cruc, and the hollow pile is built at the planned depth, and then at the tip of the pile. The so-called inner digging method of forming a bulb with cement mortar is widely used.

In order to create a bulb in the above construction method, after constructing a pile, further excavating to a predetermined depth with an auger head of an August Cru, and then withdrawing the August Cru, injecting mortar through the auger head and kneading with the excavated earth and sand. It is designed to be bulbous.

(Problems to be solved by the invention) However, in the bulb formation by the above-mentioned medium excavation method, the extraction speed of the August cruc may vary due to the soil quality of the excavated ground, and the extraction speed is not constant. If it is too slow, the mortar will be excessively supplied, and if it is too fast, the mortar will not be sufficiently supplied, and a bulb having a good predetermined strength will not be formed. Therefore, conventionally, the valve of the hydraulic circuit to the hydraulic cylinder for extracting the auger screw is frequently operated by relying on visual experience to keep the extraction speed constant, but the operation is very troublesome. The accuracy was extremely poor and it was difficult to create a good bulb.

In view of this, the present invention makes it possible to create a bulb having a predetermined strength by preventing variations in the extraction speed of the August cruc regardless of the properties of the ground, and a hydraulic cylinder speed for root consolidation in the medium excavation method. The purpose of the invention is to provide an adjusting device.

(Means for Solving the Problems) In order to solve the problems of the above-mentioned conventional technology, in the present invention, an auger screw drive device and a pile holding device, which are individually mounted on a leader mast so as to be able to move up and down independently, are provided by a hydraulic cylinder. In a pile driving machine for excavation in which the vertical relative positions are adjustable, a detection device for detecting the stroke and extension speed of the hydraulic cylinder, and the extension speed detected by this detection device and the preset extension speed. And a control device for controlling the hydraulic oil supply hydraulic circuit to the hydraulic cylinder.

(Operation) If the pulling speed of the auguscre is changed in the process of injecting the mortar while pulling up the auger screw, the detecting device detects the change in the speed and the signal is input to the control device. The supply speed of the pressure oil is increased or decreased to adjust the pulling speed of the August cruc. As a result, the hydraulic cylinder immediately responds even if the pulling speed of the auguscrew increases or decreases due to the influence of the soil quality, etc., and the pulling speed of the auguscru becomes constant.

(Embodiment) Hereinafter, the present invention will be described with reference to an embodiment shown in the drawings.

FIG. 1 schematically shows an example of a hollow excavator to which the present invention is applied, in which a screw driving device 3 and a pile holding device 4 are supported by a guide rail 2 of a leader mast 1 so as to be able to move up and down. The screw drive device 3 includes an excavation mechanism 5, a reaction force receiver 6 substantially integrated with the excavation mechanism 5, and a hydraulic cylinder 7 fixed to a side portion of the reaction force receiver 6. A rod 8 of a cylinder 7 is connected, and a chuck mechanism 10 for chucking a concrete hollow pile 9 is provided below the pile holding device 7.

A detection device 11 for detecting the extension speed of the hydraulic cylinder 7 is provided on the side of the reaction force receiver 6. In the illustrated example, the detection device 11 includes an encoder 12 provided on the reaction force receiver 6, a wire rope 13 wound around the encoder 12 and having one end fixed to the pile holding device 4, and a wire rope 13 of the wire rope 13. The hydraulic cylinder 7 is extended and the drive device 5 is raised with respect to the pile holding device 4 to pull up the auger screw 15 so that the wire rope 13 is fed out. The encoder 12 is rotated by the wire rope 13 to transmit a pulse signal, and the extension speed of the hydraulic cylinder 7 is detected.
The detecting means is not limited to the one using the wire rope 13 and may be another means.

An auger screw 15 having an upper end supported by the drive device 5 is inserted into the hollow pile 9, and the auger head 1 is attached to the lower end thereof.
6 is provided so that the mortar is sprayed in a substantially horizontal direction as usual. In FIG. 1, reference numeral 17 is a wire rope for suspending the whole including the drive device 5 on the leader mast 1 so as to be able to move up and down, 18 is its sheave, and 19 is a wire rope for suspending the pile holding device 4.

2 (A) to (C) show the excavation of the ground 19 by the auger cru 15, and FIG. 2 (A) shows a state in which the auger head 16 has been excavated to a predetermined depth. B) shows the process of injecting the mortar 20 while pulling up the auger screw 15, expanding the diameter of the hole in the ground 19 to form the bulb 21, and FIG. 2C shows the auger screw 15 in a uniform manner. It shows a state in which the bulbs 21 having a uniform outer diameter and properties are formed by pulling at a speed.

FIG. 3 shows a control system for keeping the pulling speed constant. When the detector 11 detects that the pulling speed of the auger screw 15 has changed for some reason, the detection signal is input to the control unit 22. This control unit 22
Thus, the valve stand 23 is controlled to increase / decrease the amount of pressure oil supplied to the hydraulic cylinder 7 to rapidly expand / contract.

The specific operation will be described with reference to the flowchart shown in FIG. 4. In the excavation process, when the start button is operated, the automatic operation button is turned on, the hydraulic cylinder 7 is shortened, and the auger screw 15 excavates. Be done. When August Cru 15 reaches the lower limit position,
Stop for the specified time and move to the drawing process. When the lower limit position has not been reached, the excavation is further advanced at the specified speed, and when it is fast, the excavation is temporarily stopped, and when it is slow, the hydraulic cylinder 7 is shortened to proceed with excavation.

In the pulling-out process, the hydraulic cylinder 7 is extended and pulled up to the upper limit position. If the hydraulic cylinder 7 is faster than the designated speed, the hydraulic cylinder 7 is temporarily stopped. Such an operation is performed by the detection device 11 and the control device 22, and the auger screw 15
With a constant pulling speed, the mortar 20 jetted from the auger head 16 and the mixing ratio of the excavated earth and sand are appropriately maintained, and the high-strength bulb 21 is formed to have a uniform thickness.

[Effect of device]

As described above, according to the present invention, in the pile driving machine for medium excavation, the speed change at the time of pulling up the auger screw is detected by the detection device, and based on the detection signal, the control unit detects the pressure oil to the hydraulic cylinder. Since the amount of supply is controlled, when the speed of pulling the auger screw changes, the amount of pressure oil supplied to the hydraulic cylinder can be increased or decreased to make the pulling speed appropriate, and the mortar injected from the auger head It is possible to locally prevent excess and deficiency, and to form a bulb having a predetermined strength.

[Brief description of drawings]

FIG. 1 is a schematic side view showing an outline of a pile excavator for medium excavation to which the present invention is applied, FIGS. 2 (A) to 2 (C) are explanatory views showing a bulb forming process, and FIG. 3 is the same control system. FIG. 4 is a flowchart of the same. 3 ... Screw drive device, 4 ... Pile holding device, 5 ... Excavation mechanism, 6 ... Reaction force receiving, 7 ... Hydraulic cylinder, 9 ... Hollow pile, 10 ... Chuck mechanism, 11 ... Detection device , 15
…… August Cru, 16 …… Auger Head, 21 ……
Bulbs

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Claims (1)

[Scope of utility model registration request] 1. A hollow excavating pile driving machine in which an auger screw driving device and a pile holding device, which are mounted on a leader mast so as to be able to move up and down independently of each other, are connected by a hydraulic cylinder so that the vertical relative position can be adjusted. Detecting a stroke and an extension speed of the control device, and a control device for comparing the extension speed detected by the detection device with a preset extension speed to control the hydraulic oil supply hydraulic circuit to the hydraulic cylinder. A hydraulic cylinder speed adjusting device for consolidation in a medium excavation method, characterized by comprising: