JPH02171418A - Pile press-fitting machine - Google Patents

Abstract

PURPOSE:To make it possible to reduce costs by enabling a leader support jib to be extended and retracted and to be folded so that the leader support jib can retract and restore its external shape by itself so that the disassembly thereof is not required during transportation thereof. CONSTITUTION:A jib 3 on a vehicle is composed of a base jib 3a, a slidable jib 3b and a front end jib 3c which a slidably supports a leader 1. Further, during transportation the slidable jib 3b is retracted so as to lower the rotational center of vertical swing motion of the leader 1, and then the front end jib 3c is folded toward the side remote from the leader 1 by means of a link mechanism 50, and accordingly, the leader 1 is laid horizontally on the body of a vehicle. Further, during working the jib 3 is expanded and then extended so as to stand and support the upper section of the leader 1, and a lock mechanism is provided so as to prevent accidental retraction of the slidable jib 3b. With this arrangement, the external shape of a machine incorporating the leader can be contracted without the leader being removed, and accordingly, it is suitable for use in a narrow job site. Further, it is possible to reduce the labor cost and the mechanical cost incurred by the disassembly of the jib during transportation.

Description

[Detailed description of the invention] (Purpose of the invention) (Industrial application field) The present invention relates to a pile body press-in machine.

(Conventional counter-impingement) The pile body press-in machine disclosed in Japanese Patent Publication No. 58-27371 combines an auger screw rotation drive device and a chuck device that grips the pile body with a pair of endless drive channels. It is an excellent working machine that can move up and down simultaneously or separately using one engine, but when transporting it, it must be disassembled into the vehicle body, leader, rotary drive device, etc., and then assembled into the working position when starting work. There is.

On the other hand, when transporting the reader, the reader can be placed horizontally within the vehicle loading limit with the reader, rotation drive device, etc. equipped on the vehicle body, and when transported to a workshop etc., the reader can be moved into the working position using the self-blading blade. As something that can be restored upright, Publication No. 58-53325 Onibi Publication No. 60-3
There is a pile driver as shown in Japanese Patent No. 8757.

In this conventional pile driver, the distal end side of the jib (also called boom) that supports the leader is foldable at the base end side, and the jib (boom) is folded in half by a cylinder during forwarding. The leader is installed horizontally on the vehicle body.

When using such a pile driver to heave the leader, the force required for heave can be reduced by setting the rotation center of the heave near the leader's center of gravity (this center of gravity is located below the center of the leader). It is small and the leader is placed horizontally on the vehicle body in a well-balanced manner. On the other hand, when working with the leader upright, attach the top of the leader to the jib (boom).
It is preferable to support it at the tip.

(Problems to be Solved by the Invention) However, in conventional pile driving machines, the position at which the leader is held is determined by the tip of the jib (boom). For this reason,
When raising or lowering a leader or when supporting a leader, one or the other is sacrificed. For example, in the case of the pile driver shown in Japanese Utility Model Publication No. 58-53325, the lower part of the leader protrudes in front of the vehicle body when the leader is installed horizontally, and in the case of the pile driver shown in Japanese Utility Model Publication No. 60-38757, In this case, the upper part of the leader cannot be supported when the leader is standing.

The present invention was developed in view of these points, and is a pile body press-fitting method that allows the relationship between the jib and the leader to be optimized, whether the leader is vertically supported during work or the leader is installed horizontally during forwarding. The purpose is to provide a machine.

(Structure of the Invention) (Means for Solving the Problems) The invention of claim 1 is characterized in that a leader 1 is provided in a vehicle main body 2 by a jib 3 so as to be able to rise and fall freely, and a lower part of the leader 1 is provided in a bendable manner. In this pile body press-in machine, the jib 3 is rotatably supported on the vehicle body 2 and rotated by a jib hoisting cylinder 30, and the jib 3 is vibably inserted into the inside of the basic jib 3a. a sliding jib 3b that is extended and retracted by a hydraulic cylinder; and a tip jib 3 that is foldably connected to the tip of the sliding jib 3b on the side opposite to the leader by a folding center shaft 32 and holds the leader 1 in a vibrating manner.
A connecting pin 33 is inserted into the tip of the sliding jib 3b and the base of the tip jib 3C when the leader is erected, and is used to operate the link mechanism pivotally supported by the basic jib 3a. Between the operating part of the cylinder 46, the tip of the basic jib 3a, and the base end of the tip jib 3C, the tip jib 3 is inserted around the folding central axis 32 when the leader is raised or lowered.
It is equipped with a link of 8 m4 to 45 that rotates C.

In the invention of claim 2, the locking mechanism 80 for preventing sudden contraction of the sliding jib 3b has a locking portion 82 provided on the sliding jib 3b and a locking portion 82 provided on the basic jib 3a that locks against the locking portion 82. A removable stopper 84 and this l-tube 84
The spring 87 is actuated by the link mechanism operating cylinder 46 to force the locking mechanism 80 in the direction of engaging the locking portion 82.
The pile body press-in machine according to claim 1, further comprising a mechanism for releasing the stopper 84 against the pressure 7.

(Function) The invention of claim 1 lowers the center of rotation of the leader by reducing the jib 3 at the time of forwarding, and then folds the jib 3.
A leader 1 is placed horizontally on a vehicle body 2, and the upper part of the leader is further bent to reduce the length of the leader to a length that can be forwarded. .

Further, when working with the leader 1 erected, the jib 3 is unfolded and then extended to support the upper part of the leader 1 erectly.

The expansion and contraction of the jib 3 is performed by hydraulic cylinders built into the basic jib 3a and the sliding jib 3b. When defeating leader 1,
Fix the leader 1 to the tip jib 3C and rotate the tip jib 3C until it is parallel to the back of the basic jib 3a without falling over. The rotation of the tip jib 3C is achieved by a link mechanism 50 provided between the base end of the tip jib 3C and the tip of the basic jib 3a.
The cylinder 4 for operating the link mechanism provided on the basic jib 3a
6. At this time, the leader 1 is fixed integrally with the tip jib 3C.

When undulating the leader 1, if the center of rotation is set close to the center of gravity of the leader 1 (below the center of the leader), the force required for undulating is small and the force applied to the link mechanism 50 for undulating is also small and efficient. becomes. On the other hand, from the standpoint of strength of the leader during work, it is preferable to support the leader length at a height of 273 at the tip of the jib, as shown in FIG. Therefore, in the working posture, the sliding jib 3b is extended and the tip jib 3c is supported at a position approximately 273 degrees of the leader length, and when uphill, the sliding jib 3b is contracted and the leader 1 is
λ on the leader so that the center of rotation is located near the center of gravity of
By selecting the lengths of the basic jib 3a, sliding jib 3b, and tip jib 3C, structurally and functionally effective leader support can be achieved.

Furthermore, when the vehicle body of the pile body press-in machine moves up and down to the transport vehicle by self-propulsion, the slope of the Kushiro pitching tool is steep, so the leader, which has been knocked down horizontally, remains largely protruding in front of the vehicle body. However, in the present invention, the jib 3
Since a telescopic system is adopted for the aircraft, after the leader 1 is laid down horizontally above the aircraft, the sliding jib 3b is extended and contracted, and the leader 1 is moved rearward to adjust the balance before launching Kushiro. By doing so, stability during loading onto a transport vehicle can be improved. Furthermore, it becomes easy to keep the rear end portion of the reader 1 within the vehicle loading limit during forwarding.

According to the second aspect of the invention, when the sliding jib 3b is extended, the sliding jib 3b moves while knocking down the stopper 84 which is elastically protruding toward the sliding jib 3b by the spring 81, and the stopper 84 is in a state of protruding. The stopper 84 acts as a check against the locking portion 82 provided on the sliding jib 3b, thereby preventing the sliding jib 3b from sliding down. When the sliding jib 3b is to be retracted, the link mechanism operation cylinder 46 used for folding the boom 3 is used to release the check action of the stopper 84.

(Example) Hereinafter, a pile body press-in machine according to the present invention will be described based on an example.

As shown in FIGS. 1 to 3, the leader 1 is supported by a jib 3 and a lower support frame 4 attached to the front side of a vehicle main body 2 that can run.

The leader 1 is provided with a function for press-fitting the pile body 5 and the like using power. That is, sprocket wheels 101 and 102 are rotatably supported at the upper and lower ends of the leader 1, and the sprocket wheels 101.
A chuck device f for gripping the pile body 5 on the guide rod of the leader 1 by winding the drive chino 103 endlessly around the leader 102;
t 104 is installed so that it can move up and down, and this chuck device 1
04, a part of the drive cheno 103 is connected to the guide rod of the leader 1, and a rotary drive device R105 is attached to the guide rod of the leader 1 so as to be movable up and down separately from the chuck device 104. The upper end of an auger screw 106 disposed along the body 5 is connected to the rotary drive device ff 105 of the auger screw 106, which is connected to a sprocket wheel driven by a self-equipped vertical movement motor and the driving cheno. 103 are engaged with each other in the relationship between the binion and the rack, so that it can move vertically by itself. The lower sprocket boiler 102 is driven by a press-fit drive device 101 consisting of a hydraulic motor and a speed reducer, and the chino 103 is rotated.

The leader 1 is divided into a lower leader 1a and an upper leader lb. Both leaders 1a and 1b are rotatably connected by a hinge 8, and are bent and rotated by 90' around the hinge 8. Therefore, a V-shaped notch 9 and a connecting member 10 that connects the opposing sides through the notch 9 are provided between the lower leader 1a and the upper leader 1b.

Further, a hydraulic cylinder 11 that supports the weight of the leader 1, rotation drive device 105, etc. is attached to a bracket 12 protruding from the leader 1 with a pin 13. The rod end 14 of the cylinder 11 is supported by a pin 17 on a bracket 16 provided on the upper surface of a slide frame 15 built into the lower support frame 4.

In addition, a pair of guides 18 are provided on the back of the lower leader 1a.
A bracket 19 provided at the tip of the slide frame 15 holds the reader 1 so that it can move vertically but is restricted from rotating.

A pair of guides 20 are provided on the back side of the upper leader 1b, and a bracket 21 that is slidably fitted to the guides 20 allows the leader 1 to move up and down but is restricted from rotating. Retained.

The top sheave frame 22 has a shaft 2 at the upper end of the leader 1.
It is attached so that it can rotate around bolt 3 as a fulcrum, and when working, use bolt 2.
4 to the upper leader 1b.

The jib 3 is a telescopic type and is composed of a basic jib 3a, a sliding jib 3b, and a tip jib 3C.

The upper end of the tip jib 3C is connected to the bracket 21 by a shaft 25 having a spherical bearing.

The basic jib 3a and the sliding jib 3b are hollow and have a telescopic structure, and have a built-in hydraulic cylinder (not shown), which allows the sliding jib 3b to expand and contract.

The timber jib 3a is attached to a bracket 2 located in the center of the vehicle body 2.
It is rotatably attached to G by a shaft 27.

Further, the rod tip of a jib hoisting hydraulic cylinder 30 which is pivotally supported on the bracket 28 of the vehicle body 2 by a pin 29 is connected to the central portion of the basic jib 3a by a pin 31.

The tip jib 3C and the sliding jib 3b are rotatably connected by a folding center shaft 32. FIG. 1 shows construction of a vertical shaft, and in this case, the tip jib 3C and the sliding jib 3b are integrated by a connecting pin 33.

As shown in FIG.
The swing jib 35 is composed of two members: a swing jib 35 and a swing jib 35, and the swing jib 35 is rotated about a shaft 36 to the position shown by the two-dot chain line in FIG. 4 by expanding and contracting the hydraulic cylinder 37.

The operation of the pile body press-in machine with the above structure during work will be described.

When the vehicle body 2 moves or turns, the hydraulic cylinder 11 is extended to lift the bottom surface 38 of the lower leader 1a above the ground, and during work, the pressure of the hydraulic cylinder 11 is released to ground the leader bottom surface 38. As a result, the vertical force applied to the leader 1 is supported by the ground, so that the influence on the vehicle body 2 is small.

When the leader 1 is moved in the backward direction with the vehicle body 2 stopped, the slide frame 15 is slid and the jib 3 is rotated by the hydraulic cylinder 30.

To correct the horizontal inclination of leader 1, use the hydraulic cylinder 3.
The slide frame 1
This is done using the bracket 19 at the tip of No. 5 as a reference point.

A stopper 39 provided on the upper leader 1b is fixed to the guide 20 by bolting or the like, and if oil suddenly leaks from the hydraulic cylinder 30, it stops the WJllJ from below the bracket 21 and stops the leader. 1 is a safety stopper that prevents the risk of over-tilting forward.

Note that this stopper 39 is removed when the leader is horizontal.

Next, FIG. 5 shows the undulation of the leader 1, that is, the axis 3 until the tip jib 3C is parallel to the back surface 40 of the basic jib 3a.
2 shows a link mechanism 50 that bends around 2. This link mechanism 50 will be explained below.

The other end of the link par 42 is pivotally supported by a pin 41 on the lower side of the upper end of the basic jib 3a, and the other end of the link par 44 is pivotally supported by a pin 43 on the connecting frame 34 of the tip jib 3C.
Furthermore, the upper end of the link par 42 and the rod end 47 of the hydraulic cylinder 46 for operating the link I11 structure supported by the basic jib 3a are connected by a pin 48, and the hydraulic cylinder 46 is expanded and contracted. , the tip jib 3C is rotated about the shaft 32. Hydraulic cylinders 46 are provided on both sides of the basic jib 3a, and the pin 4
At step 9, it is attached to the basic jib 3a.

In the production posture, as shown in FIG. 1, the pin 43 is removed, the link mechanism 50 is released from the tip jib 3C, and the sliding jib 3b is extended. As shown in the figure, the sliding jib 3b is fully contracted, the hydraulic cylinder 46 is extended, and the link par 44 is extended.
is connected to the connecting frame 34 by the pin 43,
Remove the pin 33 that connects the pin hole 33b of the FI rotation knob 3b and the pin hole 33c of the tip jib 3C, and remove the pin hole 33c of the tip jib 3C.
is made rotatable around the shaft 32. Thereafter, the hydraulic cylinder 46 is contracted and the tip jib 3C is rotated until the stopper 51 provided on the connection frame 34 hits the back surface 52 of the leader 1.

In this state, as shown in the upper part of FIG.
The guide 20 of the leader 1 rotates around the pin 54.
The pin 55 inserted into the clamp 53 is inserted into the pin hole of the lower member, and the engaged state is maintained.
After the clamp 53 is disengaged as shown in the lower part of FIG. 6, the pin 55 is inserted into another pin hole in the lower member and held in that state.

After the clamp, the tip bracket 21 of the tip jib 3c
A fixing pin 58 provided on the reader 1 is fitted into a pin hole 59 provided on the leader 1. Centering in this case is performed by expanding and contracting the hydraulic cylinder 11.

Through the above operations, the leader 1 becomes integrated with the tip jib 3c. The situation is shown in Figures 3 and 5.

Next, during the construction of diagonal piles, etc., an accident should occur with the hydraulic equipment for extending and retracting the jib 3 (not shown), and the sliding jib 3 b /
J< In order to prevent the risk of slipping off, a locking mechanism 80 for preventing WIM as shown in FIGS. .

This locking mechanism 80 for preventing slipping is provided with a required number of missing racks 82 as locking parts on the bottom plate 81 of the sliding jib 3b,
By abutting the distal end surface 85 of the stopper 84 against the upper end surface 83, the sliding jib 3b is prevented from sliding down.

The stopper 84 is supported to rotate around a pin 86, and a spring 87 constantly applies a rotational force in the direction of the arrow in FIG. It is restrained by a cross member 89 which is attached to.

Rotating the stopper 84 in the opposite direction of the arrow is an operation of rotating the linker 42 from a to b in FIG. 7. That is, when the hydraulic cylinder 46 is extended, the lever 9
0 rotation causes the stopper 84 to rotate counterclockwise via the rod 91, and the action of the stopper 84 is released.

The rod 91 can move in the direction opposite to the arrow with respect to the trunnion 91a, but is prevented from moving in the direction of the arrow.

The lever 90 is supported coaxially with the hollow pin 41 that supports the link par 42. That is, the lever 90 is fixed to a shaft 92 passing through the hollow pin 41.

A lever 93 fixed to the end of the shaft 92 is connected to the link par 42 with a bolt 94, and rotational force is transmitted between the shaft 92 and the link par 42.

Next, in order to lower leader 1 to a horizontal position, jib 3
While holding the dead weight of the leader 1, rotation drive device 105, etc., remove the pin 17 at the tip of the hydraulic cylinder 11 and release the engagement between the bracket 19 and the guide 18. Then, the link mechanism 50 is moved by the hydraulic cylinder 46. to create a gap between the back surface 52 of the leader 1 and the tip 60 of the slide frame 15 by rotating the tip jib 3c through the
The rod end 14 of the hydraulic cylinder 11 is connected to the lower leader 1a.
It is connected by a pin 62 to a bracket 61 attached to the. The bracket 61 is slidable by meshing with the guide 18, and is installed at a lower position that does not interfere with the vertical movement function of the leader 1 during work, but when the leader 1 is raised or lowered, it moves within the extension stroke of the hydraulic cylinder 11. and fix it to the guide 18 with bolts 63.

When tilting this leader horizontally, the rotary drive device 10 is moved so that the center of gravity including the leader 1 and the rotary drive device 105 is located near @32 at the tip of the sliding jib 3b.
Move the 5th grade.

Thereafter, by contracting the hydraulic cylinder 30 while contracting the hydraulic cylinder 46, the leader 1 can be made horizontal as shown in FIG.

In this state, the upper part of the leader 1 is supported by the pedestal 64. As shown in FIGS. 9 and 10, the pedestal 64 is provided with a clamp mechanism that is activated by the expansion and contraction of a hydraulic cylinder 65. Both sides 66 of the guide 20 of the leader 1 are held between levers 67, and the leader 1 is clamped. In addition to restraining horizontal vibration in the left and right direction, forward and backward movement of the leader 1 is also restrained. Further, a claw 68 provided on the lever 67 prevents the leader 1 from floating up.

To load the pile body press-in machine with the leader folded onto the transport vehicle 69, the connecting pin 43 of the linker 44 is removed, the link mechanism 50 is released, the fixing pin 58 is removed, and the sliding jib 3b is extended. After moving the tip jib 3C in the direction of the arrow in FIG. 11 and fitting the fixing pin 58 into the pin hole 10 provided on the lower side of the leader 1, the sliding jib 3B is
Reduce the size and pull the leader 1 closer to the vehicle body 2.

When extending the sliding jib 3b, the hydraulic cylinder 65 for clamping the pedestal 64 is contracted to restrain the movement of the leader 1, but when the sliding jib 3b is contracted, the hydraulic cylinder 65 is contracted to the extent that the restraining force is released. stretch.

In this state, as shown in FIG.
05 etc. are moved onto the lower leader 1a by the press-fit driving device 107, and the pin 72 connecting the lower leader 1a and the connecting member 10 is removed, and the connecting member 1 is removed.
0 and the lower leader 1a, the pin 6
When the hydraulic cylinder 11 connected to the lower leader 1a by 2 is contracted, this lower leader 1a becomes the 12th
As shown in the figure, it is bent downward about the hinge 8.

Due to the loading limit of 41 vehicles, as shown in FIG. 14, before vertically bending the lower leader 1a, separate brackets 74 are installed inside the mounting seats 13 for both ends of the connecting member 10 as shown in FIG. Since .75 is provided, this bracket 74.75 is connected to the connecting member 16 and the pin 77,
78 to temporarily support the weight of the lower leader 1a, rotary drive device 105, etc.
By loosening the mounting bolt θ3 of No. 1 and extending the hydraulic cylinder 11, the bracket 61 is lowered to the lowest end of the leader 1 (the mounting position during work), and the bracket 61 is fixed at this position, and the pin 17 is If the hydraulic cylinder 11 is contracted after being removed and the connecting member I6 is made free, the lower leader 1a will be in the form of a transported load as shown in FIG. 14. In FIG. 12 and FIG.

To place the reader 1 in an upright working position, perform the above-described procedure in reverse.

When constructing diagonal piles, etc., use the specified leader 1.
In order to obtain the tilting angle, the expansion and contraction of the hydraulic cylinder 30 is locked and the sliding jib 3b is contracted.

Next, the advantages of the pile body press-in machine shown in this embodiment will be listed.

The jib 3 is telescopic and foldable, and the tip jib 3C has a structure and function that allows it to be bent with its own blade until it becomes parallel to the back surface of the basic jib 3a, so that the leader 1 and rotational drive device l 105 etc. can be easily bent during forwarding etc. While equipped, the machine's external shape can be reduced to within the vehicle loading limit, and the machine can be restored to its working position using its own blade. Therefore, when transporting the pile, there is no need for a crane for disassembly/assembly such as leader 1 or for special skills, and the work can be carried out by the operator of the pile body press-in machine and an auxiliary worker. In addition, transportation is carried out using a single trailer. Therefore, there is no need to pay for dismantling/assembling cranes, labor costs for special skilled workers, and separate transportation costs for leaders, etc., making it extremely economical. Additionally, since no assembly/disassembly crane is required, it can be applied to small workplaces, and the time required for assembly/disassembly can also be reduced, increasing operating time and improving profitability.

In addition, as a left and right vertical feed correction mechanism for the leader 1, the base point for supporting the lower part of the leader 1 is placed on the lower support frame 4 protruding from the vehicle body 2, and the upper part of the leader is attached to the swinging jib 35.
Since it has a mechanism that zeros the left and right sides, the deviation of the center of gravity due to left and right verticality correction is smaller than that of conventional models. Therefore, the lateral stability of the pile body press-in machine is improved.

Furthermore, in a pile driving machine in which the leader 1 is supported by a jib 3, by making the jib 3 telescoping, construction of diagonal piles, etc. is also possible, and the range of application to piling work is widened.

Furthermore, by sliding the leader 1 in a horizontal state relative to the vehicle body 2 using the expansion and contraction motion of the jib 3, the stability of the pile press-in machine can be ensured when loading the Kushiro onto the loading platform of the transport vehicle. .

〔Effect of the invention〕

According to the invention of claim 1, when the leader is erected and supported during bamboo farming, the upper part of the leader can be stably supported by extending the sliding jib, and when the leader is horizontally installed during transport, the sliding jib can be reduced. By lowering the folding center axis to near the center of gravity of the leader and driving the link mechanism between the basic jib and the tip jib by the cylinder provided on the basic jib to fold the jib, the jib can be folded relatively easily. With a small driving force, the leader can be brought down onto the vehicle body in a well-balanced manner.Furthermore, the horizontal leader can also be moved horizontally using a sliding jib to adjust the balance, making it easy to place the leader on the loading platform of the transport vehicle. It can also improve stability.

According to the invention of claim 2, the locking mechanism can reliably prevent the risk of the sliding aJ jib suddenly contracting during the leader erecting work, and the link mechanism operating cylinder mainly used for raising and lowering the leader. It can also be used effectively.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the pile body press-in machine of the present invention;
Figure 2 is a front view of the pile body press-in machine, Figure 3 is a side view of the leader just before it is laid down horizontally or just after it is erected, Figure 4 is a front view of the tip jib, and Figure 5 is the mechanism that bends the tip jib. 6 is a sectional view taken along the line Vl--Vl in FIG. 5, FIG. 7 is a sectional view showing the locking mechanism of the sliding jib, FIG. 8 is a sectional view taken along the Figure 10 is a front view of the reader cradle, Figure 10 is a side view, Figure 11 is a side view of the reader just after it is laid down horizontally or just before it is stood up, and Figure 12 is when the reader is loaded onto a transport vehicle. FIG. 13 is an internal structural view of the hinge portion of the leader, and FIG. 14 is a side view of the leader when the lower part thereof is bent at a right angle. 1. Leader 2. Vehicle body, 3. Jib, 3a-
- Basic jib, 3b-φ sliding jib, 3cm-tip jib, 3
0...Jib hoisting cylinder, 32...Folding center axis, 3
3...Connecting pin, 46...Cylinder for link mechanism operation, 50...Link mechanism, 80...Lock mechanism, 82...
Locking part, 84...stopper, 87...spring. Junmata rod 10g

Claims (2)

[Claims] (1) In a pile body press-in machine in which a leader is provided on a vehicle body by a jib so that it can be raised and lowered, and the lower part of the leader is provided so as to be bendable, the jib is rotatably supported on the vehicle body and the jib is rotatably supported on the vehicle body. A basic jib rotated by a luffing cylinder, a sliding jib that is slidably inserted into the basic jib and expanded and contracted by a hydraulic cylinder, and a folding center shaft at the tip of the sliding jib, which is attached to the opposite side of the leader. and a tip jib that is foldably connected to the leader and slidably holds the leader, and a connecting pin that integrates the tip of the sliding jib and the proximal end of the tip jib is inserted when the leader is erected. between the operating part of the link mechanism operating cylinder pivotally supported by the basic jib, the tip of the basic jib and the proximal end of the tip jib, the tip jib is moved around the folding center axis when the leader is raised and lowered. A pile body press-in machine characterized by having a rotating link mechanism. (2) A locking mechanism that prevents sudden contraction of the sliding jib includes a locking part provided on the sliding jib, a stopper provided on the basic jib that can be freely engaged with and detached from the locking part, and a locking mechanism that locks this stopper. a spring biased in the direction of engagement with the stop portion, and a mechanism is provided for this lock mechanism, which is operated by the link mechanism operating cylinder and releases the stopper against the spring; The pile body press-in machine according to claim 1, characterized in that: