JPH0535810B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a sand pile driving apparatus, and more particularly to a sand pile driving apparatus equipped with a sand level gauge for detecting the position of a sand surface within a hollow pipe.

≪Conventional technology≫ Traditionally, for the purpose of improving soft ground,
A so-called sand compaction method is provided as an example of a construction method in which sand is buried in the ground and compacted by applying vibrations and shocks to form a sand pile.

In other words, this sand compaction construction method consists of a hollow tube, a hopper part connected to the upper end of the hollow tube and equipped with an opening for introducing sand into the hollow tube, and vibrating the hollow tube. This is a construction method that uses sand pile driving equipment consisting of a vibrator. Usually, a hollow tube is penetrated into the ground, a predetermined amount of sand is poured into the hollow tube, the hollow tube is slightly lifted, and the tip is inserted into the ground. Sand piles are constructed by discharging sand to the outside and compacting it by applying vibration and impact to the hollow tube.

In this case, the amount of sand discharged from the hollow tube is
This is a measurement item necessary to calculate the degree of compaction of sand piles, and is normally detected by a sand level gauge that measures the position of the sand surface inside the hollow pipe before and after discharge.

To measure the sand surface inside the hollow tube of this type of sand pile driving equipment, conventionally, for example, a metal electrode plate is suspended inside the hollow tube, and a certain distance is maintained between the electrode plate and the hollow tube. A means is provided for detecting the sand surface by applying a voltage and utilizing the change in resistance between the electrode plate and the hollow tube.

Such conventional sand level gauges measure the sand level by detecting changes in electrical resistance when air is present between the electrode plate and the hollow tube, and when sand or water-containing sand is present. However, the following problems arose.

<Problems to be Solved by the Invention> In other words, in the conventional sand level gauge described above, the electrode plate is hung vertically inside the hollow tube by fixing a weight or the like and connecting an electric cord. In addition to the risk of this electrical cord being cut, the other end of this electrical cord is not integrally attached to the sand pile driving equipment, and is, for example, attached to a sand pile driving equipment that is separate from the sand pile driving equipment. Because it is connected to the leader of the base machine, etc., it is affected by the vertical movement and vibration of the hollow pipe, that is, the sand pile driving equipment, and the position of the sand surface during the pulling out of the hollow pipe and compaction of the sand pile is determined accurately. There was a problem that it was not possible to measure well.

This invention was made in view of the conventional problems as described above, and its purpose is to accurately measure the position of the sand surface when pulling out hollow pipes and compacting sand piles. It is an object of the present invention to provide a sand pile driving device capable of easily controlling the degree of compaction of sand piles.

<<Means for Solving the Problem>> In order to achieve the above object, the present invention includes a hollow tube, and an opening connected to the upper end of the hollow tube and for introducing sand into the hollow tube. and a vibrator for vibrating the hollow tube. After the hollow tube is driven into the ground, sand is thrown into the hollow tube and the hollow tube is pulled out while vibrating. In a sand pile driving device that forms a compacted sand pile in the ground, the sand pile driving device includes a sand level gauge that detects the position of a sand surface in a hollow pipe, and the sand level gauge transmits a signal. a device main body having a switch means operated by the antenna and the legs being seated on the sand surface;
A receiving antenna provided inside the upper end of the hollow tube, a winch and a rotary encoder provided on the upper part of the sand pile driving device, and a receiving antenna that is wrapped around the winch and connected to the main body of the device via a sheave. is interposed between a cable such as a chain or wire suspended in a hollow tube, the winch and rotary encoder, and a transmitting antenna, and controls the operation of the winch and rotary encoder based on the signal from the transmitting antenna. It is characterized by consisting of means.

<<Embodiments and operations>> Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a sand pile driving device according to the present invention.

As shown in the overall configuration of the sand pile driving device shown in FIG. , a coupler 22 as a hopper section having a hopper 20 for introducing sand into the inside of the hollow tube 10, and an exciter attached to the upper part of the coupler 22 that applies vibrations and shocks to the hollow tube 10. 24, and is equipped with a sand level meter as shown below.

That is, the sand level gauge includes a device main body 14 suspended in a hollow tube 10 by a wire 12, a receiver 18 equipped with a receiving antenna 16 provided at the upper end of the hollow tube 10, and a sand level gauge. A winch 34 that winds up or lowers the wire 12 is attached to the upper part of the pile driving device, that is, the exciter 24, and a rotary encoder 36 that detects the rotation of the winch 34;
The controller 38 is generally configured by the winch 34, the rotary encoder 36, and the controller 38 provided between the receiver 18.

As shown in FIG. 2, the device main body 14 includes:
A plurality of sheaves 32 have a bell-shaped case 26 with an open lower end, a lid 28 that closes this opening, and a hanging fitting 30 protruding from the upper end of the case 26.
The winch 3 provided on the coupler 22 via
4 is suspended by a wire 12 wound around the wire 12.

The amount of suspension of the device main body 14 is determined by the winch 3.
The signal is measured by a rotary encoder 36 that rotates synchronously with the receiver 18, and its output is input to a controller 38 connected to the receiver 18.

Further, the vertical movement of the device main body 14 by the winch 34 is also controlled by the controller 38.

A rod-shaped transmitting antenna 40 is protruded from the upper end of the case 26 of the device main body 14, and inside thereof there is a transmitter 42 fixed to one side of the case 26 and a transmitter 42 fixed to the other side of the case 26. A battery power supply 44 provided therein and a limit switch 46 provided upright in the center of the cover plate 28 are housed, and these are connected to each other by lead wires 48, as well as a limit switch 46 extending from one end of the transmitter 42. The book lead wire 48 is inserted through a through hole 50 formed in the upper end of the case 26 and connected to the transmitting antenna 40 .

On the other hand, a leg portion 52 is provided projecting below the lid plate 28.

The leg portion 52 is located at the lowermost end and is connected to a ring frame 54 that is seated on the sand surface inside the hollow tube 10 and a lid plate 2.
A stopper 56 protruding from the lower surface of 8 and a leg plate 58 facing the lower side are connected by a plurality of connecting frames 60 that are inclined so as to expand downward. The ring frame 54 has a large pressure-receiving surface because it makes annular contact with the sand surface, and prevents the legs 52 from sinking under the sand surface when the user is seated. The leg portion 52 is connected by a plurality of bolts 62 passing through the cover plate 28 and the leg plate 58, and the stopper 56 is connected by the urging force of a coil spring 64 attached to the outer circumference of each bolt 62. A predetermined distance is maintained between the lower end of the leg plate 58 and the upper end of the leg plate 58.

The operating portion 46a of the limit switch 46 is
It protrudes downward so as to pass through the cover plate 28, and its lower end is in contact with the upper surface of the leg plate 58, and in this state, the switch 46 is in the OFF state.

Further, the coil spring 64 is connected to the main body 14 of the device.
When it is suspended in the hollow tube 10 and has not landed on the sand surface, the vibration force generated by the vibration exciter 24 causes
The spring constant is set so that the ring frame 54 is pushed up and the operating portion 46a of the limit switch 46 does not rise and turn on.

In the sand pile driving device equipped with the sand level meter configured as described above, the position of the sand level within the hollow tube 10 is detected in the following manner.

First, after the hollow tube 10 is penetrated to a predetermined depth in the ground, sand is thrown into the tube from the hopper 20, and the winch 34 is lowered by the controller 38, and the device main body 14 is lowered.

When the ring frame 54 of the leg portion 52 is seated on the sand surface, the weight of the device main body 14 acts on the biasing force of the coil spring 64 to narrow the distance between the stopper 56 and the leg plate 58.

As a result, the limit switch 46 is turned on, the transmitter 42 is activated, and the transmitting antenna 40 is turned on.
transmits radio signals to.

A signal emitted from the transmitting antenna 40 is received by the receiving antenna 16 located above it, and is sent to the receiver 18.
The controller 38 receives this output signal and outputs the measured value of the rotary encoder 36 linked to the winch 34 to, for example, a pen recorder 66 for dotting.

Through this series of operations, the rotary encoder 36 constantly measures the hanging amount of the device main body 14, so the value output to the pen recorder 66 indicates the value of the sand surface when the ring frame 54 is seated. become.

In other words, the rotary encoder 36 is linked to the winch 34 and always indicates the suspended position of the device body 14, but it outputs a value only when the ring frame 60 is seated on the sand surface. controlled by.

On the other hand, at the same time that the controller 38 receives the received signal from the receiver 18, the winch 34
A signal is sent to the machine body 14, the ring frame 54 is separated from the sand surface, and after a predetermined period of time, for example, several seconds, a signal is sent from the controller 38 to lower the winch 34. The device main body 14 is lowered, the ring frame 54 is seated on the sand surface, the above-described series of operations are performed, and the sand surface at this point is recorded on the pen recorder 66.

Thereafter, by repeating the above-mentioned operations, the sand surface is measured intermittently, and by connecting the dots of the pen recorder 66, changes over time during the pulling out of the hollow pipe 10 and the compaction of the sand pile are measured. The winch 34
Since the rotary encoder 36 is integrally provided with the sand pile driving device, highly accurate measurement values can be obtained without being affected by vertical movement or vibration of the hollow tube 10.

<<Effects of the Invention>> As described above in detail in the embodiments, according to the sand pile driving device according to the present invention, the position of the sand surface in the hollow pipe that is being pulled out with vibration can be adjusted by In addition to being able to measure accurately without being affected by movement or vibration, the degree of compaction of sand piles can be easily managed by repeatedly measuring the sand surface position using automatic control and observing its changes over time. be able to.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a sand pile driving device according to the present invention, and FIG. 2 is an enlarged sectional view of the main part of a sand level meter. 10...Hollow tube, 12...Wire, 14...
Device body, 16...Receiving antenna, 18...Receiver, 20...Hopper, 22...Coupler, 24...
Exciter, 26... Case, 28... Lid plate, 30...
... Hanging bracket, 32 ... Sheave, 34 ... Winch, 36 ... Rotary encoder, 38 ... Controller, 40 ... Transmission antenna, 42 ... Receiver,
44...Battery power supply, 46...Limit switch,
48... Lead wire, 50... Through hole, 52... Leg, 54... Ring frame, 56... Stopper, 58... Leg plate, 60... Connection frame, 62
...Bolt, 64...Coil spring.

Claims (1)

[Claims] 1. A hollow tube, a hopper section connected to the upper end of the hollow tube and provided with an opening for introducing sand into the hollow tube, and an exciter that vibrates the hollow tube. In a sand pile driving device that drives the hollow tube into the ground, then inserts sand into the hollow tube, and pulls out the hollow tube while vibrating to form a compacted sand pile in the ground, The sand pile driving device includes a sand level gauge for detecting the position of the sand surface in the hollow pipe, and the sand level gauge has a transmitting antenna and a switch means operated by the seating of the leg on the sand surface. a receiving antenna provided inside the upper end of the hollow tube; a winch and a rotary encoder provided on the top of the sand pile driving device; and a sheave wound around the winch. A rope such as a chain or wire that suspends the main body of the device in a hollow tube is interposed between the winch and rotary encoder and the transmitting antenna, and the winch and rotary encoder are controlled based on the signals from the transmitting antenna. A sand pile driving device comprising a control means for controlling operation.