JPS5825134B2 - vibrating pile driver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of an internal combustion type vibratory pile driver used for driving and pulling out steel pipe H piles, sheet piles, etc. used for rock walls, land reclamation, river revetments, mountain retaining works, etc.

To explain the conventional vibratory pile driver, in Fig. 1゜2, 1 is a crane truck, which is a self-propelled construction vehicle equipped with general tracks, etc., and is equipped with a crane 2. A hook 4 is suspended from the tip with a wire 3.

Reference numeral 7 denotes an exciter, whose upper end is suspended from the hook 4 via a shackle 5 and a shock absorber 6 formed of a coil spring or the like.

The inside forms a cylinder 8 into which a ram 9 is inserted.

The upper space of the ram 9 forms an air buffer chamber 8a, and the lower space forms a combustion chamber 8b.

A nozzle 11 is provided on the lower end surface of the combustion chamber 8b and communicates with a fuel injection pipe 12.

Intake and exhaust holes 13 are provided on the side surface of the cylinder 8 .

Reference numeral 14 denotes a chuck, which is provided at the lower end of the main body of the exciter 7 and is capable of gripping one end of the pile 15.

Next, to explain its operation, in the above configuration, the ram 9, which has been pushed upward by compressed air or the like, falls from above to below due to its own weight, blocks the intake/exhaust hole 13, and falls further, causing the air in the combustion chamber 8b to Adiabatic compression results in high temperature and high pressure.

When fuel is injected from the nozzle 11 at an appropriate time when the humidity and pressure are high, the fuel is ignited and burned.

This combustion increases the pressure in the combustion chamber 8b, causing the ram 9 to deflect upward.

Then, as the ram 9 rises, the intake/exhaust hole 13 opens to exhaust combustion gas, and then sucks in fresh air.

As the ram 9 rises, the air in the air buffer chamber 8a is compressed, and the pressure rise due to this compression causes the ram 9 to resume its downward movement.

In this way, the ram 9 repeatedly moves up and down inside the cylinder 8 due to the explosive force of the fuel, giving vibration to the exciter 7,
Pile 1 held by chuck 14 fixed to this
The pile 15 is gradually driven into soft ground by applying vibrations to the pile 5, and a soft ground hardening agent or the like is sent through the internal hollow part of the pile 15.

Therefore, unlike a pile hammer, it does not give a strong impact in one direction.

Since the exciter 7 in such a conventional vibratory pile driver drives and pulls out the pile 15 using gas explosion pressure, the excitation force is the product of the explosion pressure and the cross-sectional area of the cylinder 8.

Therefore, a cylinder with a large horsepower will have a large cylinder diameter, making it technically difficult to manufacture.Furthermore, if you try to increase the vibration frequency by shortening the ram 90 stroke, the combustion chamber 8b will become flat, causing problems such as poor combustion. However, there was a natural limit to the size of the cylinder diameter.

In addition, the vibration exciter 7 has a frequency of vibration within unit time (number of vertical movements of the ram).
If the number of piles is low, the efficiency of pile driving will decrease, so it is necessary to increase the vibration frequency as much as possible, but there is a certain limit to the speed at which piles fall due to the compressed air in the air buffer chamber 8a and their own weight, so it is possible to speed up the fall speed. There wasn't.

Therefore, in order to eliminate the above-mentioned drawbacks and increase the pile driving ability, the present invention aims to provide a vibratory pile driver that increases the number of vibrations and has a higher excitation force than the conventional one with the same cylinder diameter. be.

Its characteristic feature is that it consists of a cylinder and a ram that reciprocates within the cylinder.One chamber formed by the cylinder and ram is a combustion chamber, and the other chamber is a sealed air buffer chamber. At least two exciters configured to move the ram in the cylinder up and down and cause vibration by the combustion of fuel injected into the combustion chamber are connected so that the axes of the cylinders coincide, and Because the rams are connected by rods, fuel is injected from above or below the ram in each cylinder, which increases the vibrational force and causes the ram to move up and down.

Increase the number of times.

Therefore, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 3, two cylinders 8 are joined so that their axes coincide, and a ram 9a is provided within the two cylinders 8.

9b are connected by a rod 16, and the rod 16 passes through a hole 18 bored in the center of an intermediate partition wall 1T formed by the end surfaces of the two cylinders 8.

The upper and lower end surfaces of the rams 9a and 9b connected by the rod 16 form combustion chambers 8a and 8b, respectively, and are provided with fuel injection nozzles 11a11b, respectively.

The hole 18 in the partition wall 17 between the cylinders and the rod 16 are shaped like piston rings and are substantially sealed.

- Other members are the same as those of the conventional one, and the same parts are given the same reference numerals with suffixes a and b in the drawings.

The upper part of the vibrator 7 configured in this manner is connected to the shackle 5 via the buffer 6 as in the conventional case.

A chuck 14 is provided at the bottom of the chuck 14.
Hold the stake.

Next, the operation will be explained. When the rams 9a and 9b are pushed upward by the starting air and the like and then lowered by their own weight, the air in the lower combustion chamber 8b is adiabatically compressed and becomes high temperature and high pressure, and the fuel is discharged from the nozzle 11b. The injection causes an explosion, and the pressure inside the combustion chamber 8b becomes high, pushing up the ram 9b.

When the ram 9b rises, the ram 9a connected by the rod 16
compresses the air in the combustion chamber 8a and becomes high temperature and high pressure.

Then, fuel is injected by the nozzle lla, resulting in a combustion explosion, and the rams 9a, 9b change from upward movement to downward movement due to the pressure increase and compression pressure of the air buffer chamber 10b.

In this way, the exciter 7 of this vibratory pile driver includes the ram 9a,
In the conventional method, the excitation force is only P and A due to the product of the pressure P in the combustion chamber and the cross-sectional area A of the cylinder, but as in this embodiment, the If configured as follows, the repulsive force of the air buffer chambers 10a and 10b is added to the above-mentioned vibrational force to generate a vibrational force of approximately 2 PA.

In this way, the pile 15 is driven in and pulled out.

Next, various embodiments of the present invention will be explained. The second embodiment shown in FIG. 4 has the ram 9a in the first embodiment,
Air buffer chamber 10a in the first embodiment on the side to which rod 16 of 9b is fixed.

10b is used as a combustion chamber, and nozzle 11a'.

11 tA-provided in air buffer chambers 10a and 10b, respectively.

In the third embodiment shown in FIG. 5, a nozzle 11b' is provided in the air buffer chamber 10b of only one cylinder.

Therefore, in FIGS. 4 and 5, the nozzle 11a.

The sides where 11al and 11b/ are not provided are all air buffer chambers.

Its operation is exactly the same as in the first embodiment.

In the fourth embodiment shown in FIG. 6, a plurality of cylinders are connected in series, and each cylinder 81, 82...
Inner ram 9L 92...9n, rod 16L
162...They are bonded at 16n.

The nozzles 111, 112...11n are provided on both sides or one side of the rams 91,92...9n as required.

The rest is the same as the first to third embodiments.

With this configuration, the excitation force is added each time the number of cylinders is increased, so it can be used when a large horsepower (excitation force) is required.

This is particularly effective when increasing horsepower (excitation force) without increasing the cylinder diameter.

As described above, according to the present invention, a plurality of vibration exciters that generate vibrations due to the vertical movement of the rams in the cylinders are connected so that the axes of the cylinders coincide, and the rams in each cylinder are connected by rods. As a result, the excitation force and frequency increase.

Furthermore, since the vibrator is constituted by such opposed histonics, the return time of the ram can be shortened and work efficiency can be increased.

[Brief explanation of drawings]

Figure 1 is a side view showing the pile driving method using a vibrating pile driver.
Fig. 2 is a sectional view of a conventional internal combustion type vibratory pile driver, Fig. 3 is a sectional view showing a first embodiment of the present invention, and Figs. 4 to 6 show second to fourth embodiments of the present invention. FIG. 6...Buffer, 7...Exciter, 8...
...Cylinder, 8a, 8b... Combustion chamber, 9
a+ 9b... Ram, 10a, 10b...
... air buffer chamber, 11 ... fuel injection nozzle,
13... Intake and exhaust hole, 16... Rod.

Claims (1)

[Claims] 1 Consisting of a cylinder and a ram that reciprocates within the cylinder, one chamber formed by the cylinder and ram is a combustion chamber, and the other chamber is a sealed air buffer chamber, and the fuel injected into the combustion chamber. At least two vibration exciters are configured to move the ram in the cylinder up and down and cause vibration by the combustion of
A vibratory pile driver characterized in that two or more cylinders are connected so that their axes coincide, and the rams in each cylinder are connected with a rod.