JP6193031B2 - Pile driver - Google Patents

Description

  The present invention relates to a safety device for safely placing a leader in a standing state when a pile driving machine of a type in which the leader is placed in a lying state and a lower leader is bent and conveyed is placed on the spot.

  The size of the pile driver differs depending on the site. In many cases, the leader used in the pile driver disassembles and conveys when the pile driver is large, and bends and conveys when the pile driver is small.

  In patent document 1, the technique about the leader recombination method of a pile driver is disclosed. A pile driver that can be reconfigured into a long specification and a short specification for the operation of the pile driver. For transportation, the upper leader and intermediate leader are removed from the pile driver, and the work device (auger) is attached to the lower leader. It is in a state where it is lying on the base machine diagonally. Many large pile drivers improve the portability by increasing the number of divisions in this way.

  In patent document 2, the technique about the leader support structure of a pile driver is disclosed. In patent document 3, the technique about a pile driver is disclosed. The pile driver disclosed in either Patent Document 2 or Patent Document 3 is also configured to disassemble and remove the upper leader during transportation, and to tilt the intermediate leader to the base machine side, in which case the lower leader is the same Maintaining posture. Backstay cylinders are used for standing and lodging of the intermediate leader. At the time of transport, it is possible to transport the reader to the base machine with the reader lying down. However, there are cases in which an elastic material, a contact member, or the like as shown in Patent Document 3 is required.

  In patent document 4, the technique about the leader lying method of a pile driver and a pile driver is disclosed. In the case of this pile driver, the upper leader is not removed from the intermediate leader, but is shortened by bending, while the lower leader is also folded and shortened from the intermediate leader to be in a conveying state.

  As described above, the pile driver has various shapes depending on the size and application. Generally, the large type carries the leader by disassembling, the middle type carries the leader by folding, and the small type carries the leader. There are many cases where they fall and carry.

JP 2010-47995 A JP 2007-23640 A JP 2005-282062 A JP 2003-41584 A

  However, depending on the site, you may want to use a large type, but there are cases where a pile driver that is slightly larger than the medium size is required due to the size of the base machine of the pile driver and the small turning performance. Such a type is useful at construction sites. In this case, it is desirable that the upper reader is removed and the lower reader is bent and conveyed. However, Patent Document 4 does not describe how the lower reader is bent from the intermediate reader, and Patent Document 2 and Patent Document In the third method, the intermediate leader is bent from the lower leader by shrinking the backstay cylinder.

  However, in the case of the method described in Patent Document 2 or Patent Document 3, if the backstay cylinder is mistakenly operated and the backstay cylinder is excessively extended, the intermediate reader and the lower reader interfere with each other, and the conveyance link or reader There is a risk of damage. For this reason, in patent document 3, in order to prevent it, the elastic member which functions as a shock absorbing material is provided. However, since the cost for attaching such parts and the consumables need to be replaced regularly, there is a risk of increasing costs. Further, it is preferable to connect the intermediate leader and the lower leader with a bolt or the like during operation of the pile driver, but there is a problem that the side close to the base machine is difficult to enter and has poor workability.

  For this reason, as shown in FIGS. 3 and 4 to be described later, the applicant makes the intermediate leader attached with the upper leader obliquely tilted from the lying down state by the backstay cylinder, and is bent from one intermediate leader. It also proposes a way to stretch As described above, by holding the reader at a predetermined angle with respect to the base machine, it is possible to improve the workability of connecting the lower reader and the intermediate reader. On the other hand, if the lower leader is bent from the intermediate leader and the backstay cylinder is extended to raise the intermediate leader from the lying down state, the lower leader interferes with the base machine or the ground.

  Such a problem may occur because the operator is required to perform an operation such as raising the lower leader while raising the intermediate leader. Due to such an erroneous operation, the internal pressure of the cylinder provided to extend the lower leader from the intermediate leader may rise or fall due to the influence of the lower leader interfering with the ground or the base machine. There is a risk of damage to the material.

  Therefore, in order to solve such a problem, an object of the present invention is to provide a pile driver that can prevent a cylinder from being damaged due to an erroneous operation when a fallen leader is raised.

  In order to achieve the above object, a pile driving machine according to an aspect of the present invention has the following characteristics.

(1) The reader is provided so that it can be switched between a standing state and a lying state, and the reader has a lower leader provided with a working device so that it can be bent. A cylinder is used for bending the lower leader, and hydraulic pressure is used to drive the cylinder. In a pile driving machine having a circuit, when the cylinder is extended to the forward end and the lower leader is bent with respect to the leader, the hydraulic circuit of the cylinder applies a certain force to the lower leader. A hydraulic adjustment mechanism is provided for adjusting the hydraulic pressure applied to the inside of the cylinder so as to be within a predetermined range.

  According to the aspect described in the above (1), it is possible to prevent the working device (auger) attached to the lower leader from being damaged or the cylinder from being damaged. This is because, as shown in the problem, when the pile driver is transported, the leader is in a lying state, the lower leader is folded, and the leader of the pile driver is raised at the work site. The leader is raised in a bent state, causing a problem that the working device (auger) attached to the lower leader is damaged or the cylinder is damaged.

  This is because the lower leader is located at a position where the lower leader is bent with respect to the intermediate leader at the cylinder forward end. As a result, an external force acts on the lower leader, resulting in an increase in the cylinder internal pressure. There is a risk of damage from the weakest part of the system, the hinge part that rotatably supports the lower leader and the intermediate leader. In order to avoid this, there is provided a hydraulic pressure adjusting mechanism that adjusts the hydraulic pressure related to the inside of the cylinder within a predetermined range when a certain force is applied to the lower leader. As a result, it is possible to prevent damage to the lower leader, the cylinder, or the working device.

(2) In the pile driving machine according to (1), the hydraulic pressure adjusting mechanism is configured such that a relief valve is connected to the hydraulic circuit, a forward side circuit of the cylinder, and a check valve and an oil tank are connected to the backward side circuit of the cylinder. Are connected, and the relief valve preferably opens the relief valve when the forward hydraulic pressure becomes equal to or higher than a set pressure.

  According to the aspect described in (2) above, when a relief valve is provided in the forward circuit, an external pressure is applied to the cylinder at the forward end, and the hydraulic pressure in the forward circuit in the cylinder increases. The hydraulic pressure can be lowered on condition that the pressure becomes equal to or higher than the pressure. On the other hand, since the reverse side circuit is provided with a check valve, even if the reverse side circuit is damaged and oil leaks, the cylinder internal pressure is maintained so that the cylinder does not move, that is, the lower leader moves. I can stop it. Also, by providing an oil tank in the reverse circuit, oil can be supplied from the oil tank when the cylinder internal pressure changes, and it is possible to prevent damage to the cylinder and the like.

(3) In the pile driving machine according to (2), it is preferable that the relief valve is provided with a warning means that activates a warning when the relief valve is activated.

  According to the aspect described in (3) above, it is possible to notify the operator that the alarm is activated by the alarm means that the alarm means is loaded on the lower reader by the operation of the relief valve.

It is a side view of a pile driver of this embodiment. It is a side view of the pile driver of the state which removed the working device and the upper leader of this embodiment. It is a side view of the pile driver which raises the leader of this embodiment. It is a side view of the pile driver which raised the leader and extended the lower leader of this embodiment. It is a side view showing a motion of the lower leader of this embodiment. It is a hydraulic circuit diagram connected to the lower leader bending cylinder of this embodiment. It is a side view which shows the mode of the pile driver which raised the leader, bending the lower leader of this embodiment. It is an enlarged view of the lower reader vicinity of FIG. 7 of this embodiment. It is a circuit diagram which shows the hydraulic circuit prepared for the comparison.

  First, an embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, the side view of the pile driver 100 of this embodiment is shown. FIG. 2 shows a side view of the pile driving machine 100 with the working device 140 and the upper leader 131 removed. The pile driving machine 100 is a machine in which a work machine unit 120 is provided above the lower traveling body 110, a leader 130 provided in the work machine unit 120 is erected, and excavation work can be performed by the work device 140. .

  The work machine unit 120 is provided with an outrigger 121, and the outrigger 121 can be widened to prevent falling when working. The reader 130 includes an upper reader 131, an intermediate reader 132, and a lower reader 133, and the intermediate reader 132 is attached to the work machine unit 120. When the pile driver 100 is transported, the upper leader 131 is detached from the intermediate leader 132 and the lower leader 133 is bent in the state shown in FIG. At this time, the working device 140 attached to the lower reader 133 has been removed.

  FIG. 3 shows a side view of the pile driving machine 100 raising the leader 130. FIG. 4 shows a side view of the pile driving machine 100 with the leader 130 raised and the lower leader 133 extended. The upper reader 131 is connected to the intermediate reader 132, and the first reader upright cylinder 122 provided in the work machine unit 120 is connected to the back of the intermediate reader 132 via a link, and the first reader upright cylinder 122 is connected. 3, the reader 130 can be raised as shown in FIG. 3 around the reader fulcrum 135 provided at the lower part of the intermediate reader 132.

  FIG. 4 shows a state in which the first leader upright cylinder 122 is fully extended. To raise the position of the reader 130 further from here, a second leader upright cylinder 123 provided separately from the first leader upright cylinder 122 is provided. It is necessary to use it. The second leader upright cylinder 123 is provided in the work machine unit 120, and by extending the second leader upright cylinder 123, the leader 130 can be held perpendicular to the ground.

  On the other hand, the lower leader 133 is bent at a right angle with respect to the intermediate leader 132. FIG. 5 is a side view showing the movement of the lower reader 133. The lower leader 133 is provided with a lower leader bending / extending cylinder 133b, and the lower leader 133 is bent with respect to the intermediate reader 132 around the lower leader fulcrum 133a by extending / contracting the lower leader bending / extending cylinder 133b. When the lower leader fulcrum 133a is at the forward end, the lower leader 133 bends 90 degrees with respect to the intermediate leader 132, and when it is at the retracted end of the lower leader bending cylinder 133b, the lower leader 133 is straight with respect to the intermediate leader 132. It is arranged in the position. In this state, the lower leader 133 is fixed to the intermediate leader 132 using a bolt or the like, and excavation work is performed by moving the working device 140 up and down.

  FIG. 6 shows a hydraulic circuit diagram connected to the lower leader bending cylinder 133b. The lower leader bending cylinder 133b is provided with a rod side port 133A and a bottom side port 133B, and is connected to the hydraulic circuit 150. A flow rate adjustment valve 151 and a single operation check valve 152 are connected to the rod side port 133A side, and are connected to the first port 155A of the direction switching valve 155. Note that an oil tank 154 and a check valve 153 are provided in a pipe branched from the first port 155A. On the other hand, connected to the second port 155B provided in the direction switching valve 155 are a flow rate adjustment valve 151 and a relief valve 156 disposed between the single operation check valve 152 and the bottom side port 133B. An oil tank 154 is connected to the tip of the relief valve 156.

  A hydraulic pump (not shown) is connected to the P port of the direction switching valve 155, and an oil tank (not shown) is connected to the T port. Since the direction switching valve 155 is a three-position center-closed type, when it is desired to move the lower leader bending cylinder 133b to the forward end side, the P port is connected to the second port 155B and connected to the bottom port 133B of the lower leader bending cylinder 133b. Supply oil. On the other hand, when it is desired to move the lower leader bending cylinder 133b to the backward end side, the P port is connected to the first port 155A side, and oil is supplied to the rod side port 133A of the lower leader bending cylinder 133b. In this way, the lower leader 133 can be bent and stretched.

  The pile driving machine 100 has the above-described configuration, and prepares for work according to the following procedure. First, in the state of FIG. 2, the pile driving machine 100 is transported using a trailer (not shown), and upon arrival at the work site, the working device 140 is attached to the lower leader 133 and the upper leader 131 is fixed to the intermediate leader 132 with bolts. . In this operation, it is preferable to use the outrigger 121 as necessary.

  After that, as shown in FIG. 3, the first leader standing cylinder 122 provided in the working unit 120 is extended, and at the same time, the lower leader 133 is expanded by contracting the lower leader bending cylinder 133b. The lower leader 133 and the intermediate leader 132 are bolted to the state shown in FIG. 4, that is, in a state where the first leader standing cylinder 122 is extended and the lower leader bending cylinder 133 b is moved to the retracted end and the lower leader 133 is extended. As described above, the operation of the first leader standing cylinder 122 and the operation of the lower leader bending cylinder 133b are alternately performed to wake up the reader 130, and then the second leader standing cylinder 123 is extended to move the reader 130. Stand upright. In this way, the excavation work of the ground 50 by the pile driver 100 becomes possible.

  Since this embodiment is the said structure, there exists an effect | action and effect which are demonstrated below.

  First, there is an effect that it is possible to prevent the lower leader bending / stretching cylinder 133b from being damaged by an erroneous operation when the fallen leader 130 is raised. This is because the pile driving machine 100 according to this embodiment includes a reader 130 that can be switched between a standing state and a lying state, and the reader 130 can bend a lower reader 133 that includes a working device 140. In the pile driving machine 100 using the lower leader bending / stretching cylinder 133b for bending and driving the lower leader bending / stretching cylinder 133b with the hydraulic circuit 150, the lower leader bending / stretching cylinder 133b extends to the forward end, and the lower leader 133 is made to the leader 130. The hydraulic circuit 150 of the lower leader bending cylinder 133b adjusts the hydraulic pressure applied to the inside of the lower leader bending cylinder 133b to be within a predetermined range when a certain force is applied to the lower leader 133 in a state where the cylinder is bent. This is because the structure is provided with a relief valve 156 serving as a mechanism.

  FIG. 7 is a side view showing a state of the pile driving machine 100 in which the leader 130 is raised while the lower leader 133 is bent. FIG. 8 shows an enlarged view of the vicinity of the lower reader 133 in FIG. The pile driving machine 100 shown in FIGS. 7 and 8 is in a state where the leader 130 is raised by the first leader standing cylinder 122 while the lower leader 133 is bent. Normally, it is necessary to raise the reader 130 while extending the lower reader 133 as described above. In this case, the lower reader 133 is bent with respect to the intermediate reader 132 with the working device 140 attached to the lower reader 133. It is raised by the first leader upright cylinder 122 while being kept.

As a result, as shown in FIG. 8, problems such as the working device 140 interfering with the ground 50 and the lower reader 133 interfering with the working machine unit 120 or the outrigger 121 are caused.
At this time, a force is generated to cause the lower leader bending cylinder 133b included in the lower leader 133 to contract. As a result, as shown in FIG. 6, the internal pressure on the bottom port 133B side of the hydraulic circuit 150 connected to the lower leader bending cylinder 133b increases. However, a relief valve 156 is provided in the line from the bottom port 133B to the second port 155B, and when the internal pressure becomes equal to or higher than a predetermined pressure, the relief valve 156 is activated and oil is supplied to the oil tank 154. Released. As a result, it is possible to prevent damage to the lower leader bending cylinder 133b and the hydraulic circuit.

  FIG. 9 is a circuit diagram showing a hydraulic circuit 160 prepared for comparison. Conventionally, like the hydraulic circuit 160, a double operated valve 158 is provided between the direction switching valve 155 and the lower leader bending / extending cylinder 133b. This is because from the second port 155B to the double operated valve 158 is connected by the tube 159, and when this portion is damaged, consideration is given so as not to change the position of the lower leader bending cylinder 133b. .

  However, when the situation shown in FIGS. 7 and 8 occurs, the internal pressure between the double operated valve 158 and the first port 155A, which is a part of the hydraulic circuit 160 shown in FIG. The internal pressure between the valve 158 and the second port 155B increases. As a result, the hydraulic devices such as the lower leader bending cylinder 133b and the double operated valve 158 may be damaged, and in the worst case, they may be damaged.

  In order to prevent such a situation, in this embodiment, the lower leader bending / extending cylinder is provided with a hydraulic adjustment mechanism that lowers the hydraulic pressure when a predetermined pressure is generated, such as a relief valve 156 provided in the hydraulic circuit 150. It becomes possible to prevent breakage of 133b, the second tube 159b, and the like. If such a hydraulic circuit breaks during the work, the work cannot be continued. Therefore, it is possible to avoid such a situation by providing a hydraulic pressure adjusting mechanism.

  In addition to the relief valve 156, a single-operated check valve 152, an oil tank 154, and the like are provided as a hydraulic pressure adjustment mechanism. Therefore, the hydraulic pressure on the rod side of the lower leader bending cylinder 133b is not released by the action of the single operated check valve 152, and the lower leader 133 can be prevented from unintentionally bending. In addition, when the bottom side hydraulic pressure of the lower leader bending cylinder 133b is increased, the relief valve 156 is opened, while the rod side hydraulic pressure of the lower leader bending cylinder 133b is decreased. It is prevented by supplying. Either configuration can contribute to the protection of the hydraulic circuit 150.

  In addition, a sensor (not shown) for detecting the operation of the relief valve 156 is provided, the sensor confirms the operation of the relief valve 156, and reports an abnormality to an alarm means, for example, an operation panel operated by an operator of the pile driver 100. Or by providing an alarm device that sounds a buzzer, it is possible to promptly notify the operator of the abnormality and prompt the user to confirm the operation by stopping the operation. As a result, it is possible to minimize damage to the pile driving machine 100 even if an operation is performed in the wrong procedure.

  Although the invention has been described according to the present embodiment, the invention is not limited to the embodiment, and by appropriately changing a part of the configuration without departing from the spirit of the invention. It can also be implemented. For example, as long as the hydraulic circuit 150 is a circuit that performs the same function as this, it does not prevent other configurations from being employed. Also, the pile driver 100 does not prevent the present invention from being applied to the pile driver 100 having a different configuration, such as a method of bending the upper leader 131 with respect to the intermediate leader 132.

DESCRIPTION OF SYMBOLS 100 Pile driver 110 Lower traveling body 120 Working machine part 121 Outrigger 122 1st leader standing cylinder 123 2nd leader standing cylinder 130 Leader 131 Upper leader 132 Intermediate leader 133 Lower leader 133a Lower leader fulcrum 133b Lower leader bending cylinder 135 Leader fulcrum 140 Working device 150 Hydraulic circuit 151 Flow adjustment valve 152 Single operation check valve 153 Check valve 154 Oil tank 155 Direction switching valve 156 Relief valve 158 Double operation valve

Claims (3)

The reader is provided so that it can be switched between a standing state and a lying state, the reader has a lower leader provided with a working device, and a lower circuit is foldable. A cylinder is used for bending the lower leader, and a hydraulic circuit is used to drive the cylinder. In the pile driver,
In a state where the cylinder extends to the forward end and the lower leader is bent with respect to the leader, the hydraulic circuit of the cylinder applies a predetermined hydraulic pressure to the inside of the cylinder when a certain force is applied to the lower leader. includes a hydraulic adjusting mechanism for adjusting to fit a range of,
The hydraulic adjustment mechanism, Rukoto relief valve is connected to the forward side circuit of the cylinder is the hydraulic circuit,
Pile driver characterized by. The reader is provided so that it can be switched between a standing state and a lying state, the reader has a lower leader provided with a working device, and a lower circuit is foldable. A cylinder is used for bending the lower leader, and a hydraulic circuit is used to drive the cylinder. In the pile driver,
In a state where the cylinder extends to the forward end and the lower leader is bent with respect to the leader, the hydraulic circuit of the cylinder applies a predetermined hydraulic pressure to the inside of the cylinder when a certain force is applied to the lower leader. Equipped with a hydraulic adjustment mechanism to adjust to fit within the range of
The hydraulic adjustment mechanism has a relief valve connected to the forward circuit of the cylinder, a check valve and an oil tank connected to the backward circuit of the cylinder,
The relief valve is configured to open the relief valve when the hydraulic pressure of the forward circuit becomes equal to or higher than a set pressure;
Pile driver characterized by. In the pile driver according to claim 2,
The relief valve is provided with an alarm means for activating an alarm when the relief valve is activated;
Pile driver characterized by.

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