JPH03161614A - Vibration generator and vibrating pile-driver - Google Patents

Abstract

PURPOSE:To constitute a vibration generator longitudinally and compactly by installing first and second unbalanced weights to three vertically arranged shafts and determining the mass and eccentric quantities of the weights so as to satisfy specific relationship. CONSTITUTION:Second shafts 2, 2 are installed at a regular interval in the vertical direction of a first shaft 1 respectively and three-shaft vertical arrangement is obtained, and each shaft 1, 2, 2 is coupled through gears 1A, 2A, 2A. A driving motor is connected to either of each shaft 1, 2, 2, and a first unbalanced weight 1B is mounted to the first shaft 1 and second unbalanced weights 2B, 2B to each second shaft 2, 2 respectively. The mass m1, m2, m2 and eccentric quantities r1, r2, r2 of the first and second unbalanced weights 1B, 2B, 2B are determined so as to satisfy m2r2=m1r1/2, thus constituting a vibration generator. When the first unbalanced weight 1B is turned up to a left position, each working horizontal centrifugal force F1, F1/2 works in the opposite direction and is offset because the upper and lower second unbalanced weights 2B, 2B are rotated reversely and reach to a right position.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a vibration generator and a system that uses vibration to perform piling or piling work, which is a type of civil engineering work, using the vibration generator as a vibration generator. Regarding the vibrating pile driver.

[Prior art] In general, this type of vibrating pile driver is
The one disclosed in Publication No. 085 is known. That is, as shown in FIGS. 6(a) and 6(b), the stationary frame 13 suspended from the crane hook l2 is equipped with an exciter l4.
is a buffer spring 15 attached to a vibration frame (not shown).
It is attached via. The pile 10 to be driven is gripped by a chuck 16 provided at the bottom of the exciter l4.

FIG. 5 shows the vibration generation principle of the vibrator l4 used in this conventional vibratory pile driver.

Generally, as a mechanism for generating vibrations, a method of rotating a pair of unbalanced weights 17B, 17B is widely adopted. In particular, in a vibratory pile driver, the direction of vibration needs to be vertical, and the vibration of a circular trajectory generated by the rotation of unbalanced weights 17B, 17B attached to the rotating shafts 17, 17 is converted into an upward and downward linear trajectory. two axes l to convert into vibrations of
7 and 17 are arranged horizontally in parallel, and gears 17A and 17A attached to both shafts 17 and 17 are meshed with each other. One of the shafts is used as a drive shaft and is driven by an electric motor (not shown), and the shafts are rotated in opposite directions at a constant speed to generate vertical vibration. However, in Figure 5(a) both weights 1
713 and 17B are on the lower side, and the resultant centrifugal force is 2F, which acts downward. Furthermore, when the weights iI17B and 17B rotate and come to the position shown in FIG. Furthermore, figure (C)
When it rotates to the position, a resultant force 2F of centrifugal force opposite to that shown in Figure (a) is generated upward. Further rotation (d)
When the position I11 is reached, the centrifugal force I11 is canceled out by each other as shown in Figure (b).

Only the centrifugal force that acts in the viscous and vertical directions remains, and this becomes the excitation force.

[Problem to be solved by the invention] In a vibrating pile driver to which the principle of vibration generation shown in FIG. Therefore, the entire exciter 14 has a resistance of 1
1L of walls protruding laterally from 0, such as quays and bridge columns
There was an inconvenience that you could not hit anti-10 when it was in contact with .

Therefore, in the conventional pile driving machine, a gap was created between the pile driver and the wall 11, and the continuity between the wall l1 and the pile 10 was sometimes interrupted. Also, as a matter of course, I couldn't pull out the stake that was next to the wall.

Conventionally, such cases have been dealt with by attaching a separate adapter, but since the adapter itself is heavy, it requires a considerable amount of effort to attach and detach, making the task more complicated.

Therefore, an object of the present invention is to install three shafts vertically in the vertical (longitudinal) direction and connect them to each other with gears, and to generate vertical vibration by keeping the relationship between the unbalanced weights attached to each shaft constant. In addition to providing an unprecedented 3-axis vertically arranged vibration generator configured as shown in FIG. The aim is to solve the problems of

[Means for Solving the Problem] In order to achieve this object, the vibration generator of the first invention has a three-axis vertical arrangement with second axes provided at equal intervals above and below the first axis. , upper and lower second shafts are connected to the central first shaft through gears, a drive motor is connected to either the first shaft or the second shaft, and a first unbalanced weight is provided on the first shaft,
In addition, second unbalanced weights are provided on the upper and lower second axes, and the relationship between the first unbalanced weight and the second unbalanced weight is determined.
mz r2 −+m+ r+(m., m2: first,
The mass of the second unbalanced weight, rl, r2' the same eccentricity)
It is characterized by the following.

A second invention is a vibratory pile driver comprising the above-mentioned vibration generator as an exciter.

[Effect]

In the above configuration, when the first shaft or the second shaft is driven and rotated by the drive motor, the first unbalanced mass with the first central shaft and the second unbalanced mass with the second upper and lower shafts rotate in opposite directions at a constant speed. do. Then, when both of these first and second unbalanced weights come to the upper side (or lower side), the centrifugal force acting on each of them acts in the same direction upward (or downward) and is combined. ,
When both the first and second unbalanced weights come to the left lateral position (or right lateral position), the centrifugal force acting on the first unbalanced weight and the centrifugal force acting on the second unbalanced weight are opposite. It acts in the direction and cancels out. In the end, only the combined centrifugal force in the vertical direction remains, which acts as an excitation force and generates vertical vibration.

If this vibration generation structure is adopted for the exciter of a vibratory pile driver, the entire exciter will be made vertically long and slim.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a basic configuration diagram of a vibration generator (for example, a vibration exciter for a vibratory pile driver) of the present invention. Figure 2 is an explanatory diagram of the vibration generation principle of this vibration generator.As shown in Figure 1, the first axis I
The second axes 2, 2 are vertically arranged with -1 2 and 0 in the vertical direction centered. These three axes l, 2, and 2 are provided horizontally at equal intervals in the vehicle straight (longitudinal) direction.

Gears IA, 2A, 2A are attached to the ends of each shaft 1, 2, 2, and the upper and lower gears 2A, 2A mesh with the central gear IA, respectively. These gears are all formed to have the same diameter and the same number of teeth.

A semicircular first unbalanced weight IB is attached to the IJ center first axis l, and semicircular second unbalanced masses 2B, 2B are attached to the upper and lower second axes 2, 2, respectively. ing. The first unbalanced weight 113 and the second unbalanced weight 2B have the following relationship. That is, as shown in Figure 1, the first complaint &
ii[HI! The center of gravity position G of IB, and the center 01 of the first axis 1
Let the distance between the first unbalanced weight IB (that is, the eccentricity from the axis of the first unbalanced weight IB) be 1, and the radius of the first unbalanced weight IB be R1. The center of gravity position of weight 2B is G
2 and the center 02 of the second shaft 2 (the amount of eccentricity) is r2, and the radius of the second unbalanced weight 2B is R2. Then, let F1 be the centrifugal force acting on the first unbalanced weight IB at the center in the illustrated position, and F2 be the centrifugal force acting on the second unbalanced weights 2B at the top and bottom, then in order to generate vertical vibration, Horizontal centrifugal forces need to counteract each other. Therefore, it must be F, -1rF, (1).

Here, F 1 −ml r 1 ω2F2=mz
r2 ω2 (m,, mz: masses of the first and second unbalanced weights IB and 2B, ω: rotational angular velocity) Therefore, the above equation (1) is as follows: m2 r 2 =+m+ r + ---( 2).

By the way, the shapes of the semicircular first and second unbalanced weights IB and 2B are similar, and the width direction dimension (depth relative to the paper surface) is
Analyzing the size ratio when the are the same, it is generally mCC R 2 and rcc R, so m
Therefore, from equation (2), R23=+R+”
That is, R2 one line R + 'io. It becomes 7937R I.

For example, the radius of the first unbalanced weight IB is R, -300m
m, the radius of the second unbalanced weight 2B is R2 = 2
It will be 38mm.

Therefore, the first and second unbalanced weights IB, 2B, and 2B, which have the relationship shown in equation (2) above, are connected to three axes (first axis 1, second axis 2, 2), and drive the first unbalanced weight IB and the upper and lower second unbalanced weights 2B, 2B by the drive motor 3 (see Fig. 3) through the same gears IA, 2A, 2A. Rotate in the opposite direction at a constant speed.

Then, as shown in Fig. 2(a), when the first and second unbalanced weights IB, 2B, and 2B are all in the downward position, the first unbalanced weight IB is affected by centrifugal force F1, Centrifugal force +F1 acts downward on the two unbalanced weights 2B and 2B, respectively.
In the end, as a result of these forces, 2F. will act in a downward direction.

Furthermore, as shown in figure (b), when the first unbalanced weight IB rotates to the left position, the upper and lower second unbalanced weights 2B, 2B rotate in the opposite direction and come to the right position, so the horizontal The centrifugal forces F+ and +F+ act in opposite directions and cancel each other out.

Furthermore, as shown in Figure (C), when the first unbalanced weight IB comes to the upper position, the upper and lower second unbalanced weights 2B, 2B also come to the upper position, so that the centrifugal force F. ,4! −
All Fl acts upward, and 2F+ acts upward as a resultant force.

Furthermore, as shown in figure (d), when the first unbalanced weight IB rotates to the right position, the upper and lower second unbalanced weights 2B, 2B come to the left position, so it is the same as in the case of figure (b). The centrifugal force F acting on the first unbalanced weight IB and the centrifugal force 3rF acting on the second unbalanced weight 2B are canceled out.

Thus, during one rotation, the centrifugal forces in the left and right directions are canceled out, and only the combined force 2F+ of the centrifugal forces in the vertical direction remains, which becomes an excitation force that induces vertical vibration.

FIG. 3 shows a vibratory pile driver equipped with the vibrator 4 having the above-mentioned configuration. FIG. 5(a) is a partially cutaway front view, and FIG. 2(b) is a partially cutaway side view.

In the figures, the same components as those of the vibration generator described above are indicated by the same reference numerals, and detailed explanations will be omitted.

Both ends of each shaft 1, 2, 2 vertically arranged in three stages are equipped with bearing IC, 2.
C and 2C are pivotally supported by the rotating shaft, and the end is connected to the gear IA.
, 2A, and 2A, which are in mesh with each other. A pulley 2D is attached to the upper second shaft 2, and a box-shaped body 4A is connected to the pulley 3A attached to the shaft end of the drive motor 3 via a helmet 5. Inside, the above-mentioned first shaft 1, second shafts 2, 2, first unbalanced weight IB, second unbalanced weight 1t2B, 2B, and gears 1A, 2A, 2A are installed. As mentioned above, since the structure is such that the three axes are arranged in three vertical stages, the box-shaped body 4A of the exciter 4 is slimmed down to be vertically long. In the figure, 6 is a stationary frame, and 7 is a buffer spring in which the stationary frame is interposed between rI1 and the fuselage 4A, both of which are within the width range of the fuselage 4A. 8 is an eye plate for hanging the crane. In addition, as shown in FIG. 4(b), a 1,000-step chunk 9 for gripping a pile (rope sheet pile) 10 is provided at the lower part of the fuselage 4A.

When this vibrating pile driver is used, as shown in Section 4(a), the vibrating machine 4 does not protrude laterally beyond the 1O, making it easy to drive piles (drilling) near walls. That is, wall 11
10 piles (copper sheet piles) in contact with this without any gap between
It becomes possible to work by driving in or pulling out.

〔Effect of the invention〕

According to the present invention described above, the following effects can be obtained. That is, (a) it is possible to realize a vibration generator (exciter) having horizontal commands arranged on three axes in the vertical and vertical directions.

(b) The vibration exciter itself of the vibratory pile driver has been slimmed down vertically by the 3-axis vertical arrangement, and the use of such a vibratory pile driver makes it possible to drive piles and pull out pits near walls. )
It will be possible to ensure continuity with

[Brief explanation of the drawing]

1 to 4 are explanatory diagrams of embodiments of the present invention, in which FIG. 1 is a basic configuration diagram of a vibration generator (for example, an exciter for a vibrating pile driver) according to the present invention, and FIG. (a) to (d) are explanatory diagrams of the principle of vibration generation, and Figures 3 (a) and (b) are a partially cutaway front view and a partially cutaway view of a vibrating pile driver equipped with the vibration generator as an exciter. The cutaway side view and FIGS. 4(a) and 4(b) are a front view and a side view showing the state of pile driving and bolting by a vibrating pile driver. Figures 5 (a) to (d) are diagrams of the principle of vibration generation in the exciter of a conventional vibrating pile driver, and Figures 6 (a) and (b) show the state of driving a pile against a wall using the vibrating pile driver. They are a schematic front view and a side view. 1... First axis, IA... Gear, IB... First unbalanced weight, 2... Second axis, 2A... Gear, 2B...
Second unbalanced weight, 3... Drive motor, 4... Exciter.

Claims (2)

[Claims] (1) Two second shafts are provided at equal intervals vertically above and below the first shaft to form a 3-axis vertical arrangement, and the upper and lower second shafts are connected to the central first shaft through gears, and the first shaft Alternatively, a drive motor is connected to either of the second axes, a first unbalanced weight is provided on the first axis, and second unbalanced weights are provided on the upper and lower second axes, and the first unbalanced weight is The relationship between the weight and the second unbalanced weight is m_2r_2=1/2m_1r_1(m_1, m_
2: mass of the first and second unbalanced weights, r_1, r_2: eccentricity). (2) A vibratory pile driver comprising the vibration generator according to claim 1 as an exciter.