JPS6043523A - Back-tension device for three-point support type pile driver - Google Patents

Abstract

PURPOSE:To raise the operability and safety of a back tension device by a method in which the contact of a load pressure gauge is provided in the electric circuit of a solenoid switch valve, and by the action of the load pressure guage, the solenoid switch valve is switched to take up slack in a back-tension rope. CONSTITUTION:During the operation of an auger, when cxcessive load on the auger 11 and a screw 12 is applied to the pressure gauge 28, a pressure switch 28a, is turned on. a solenoid switch valve 29 is then switched through a solenoid 32, and an oil-pressure cylinder 25 is contracted. A wire rope 22 for back tansion is always tensed under the set pressure of the relief valve 32 and a bending force corresponding to the auger is given to the leader 4. Annoying manual correction and maloperation of the rope for back tension can thus be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a back tension device for a three-point support type pile driver.

[Prior art]

'iJi As shown in the figure, the three-point support type pile driving ta1 has the main body 2.
A front bracket 3 is attached to the front part of the leader 4, the lower part of the leader 4 is pivotally supported on the front bracket 1'3, and the upper part of the leader 4 is supported by two back stays 5. The wire port -17 unwound from the drum 6 of the main body 2 is connected to the sheave 9 of the top sheave block 8 fixed to the upper end of the leader 4 and the sheave 12 of the auger 11 equipped with the screw 10.
The end 7a is pivotally connected to the top sheave block 8.

In addition, the three-point support type pile driver 1 has an auger 11 and a hammer 13 suspended from a leader 4, as shown in FIG. rotates,
A double-sided rotary type that drives piles using a combination of an auger 11 and a hammer 13, and an auger 11, a hammer 13, or a drop auger (not shown) on the front of the leader 4 shown in FIGS. 3(A) and (B). There is an end face fixed type in which a stake is driven into the suspended object, and this work is usually done on the front side of the main body 2.

Among these pile driving operations, the auger operation in particular is restricted because a large force is applied to the leader during screw propulsion during excavation and when the screw is pulled out after excavation, which acts as a bending force on the leader. To solve this problem, if a bending force commensurate with the auger side is generated from the center of the leader to the opposite side of the auger, only compressive force will be applied to the leader, and the auger work capacity can be increased. This device is a back tension device, and there are various types of devices. For example, Utsukai Showa 57-
As in No. 96235, one end of the back tension lobe is fixed to the front bracket, and the other end is passed through the sheave of the top sheave block installed on the top of the rotating leader, and then attached to the rond of the hydraulic cylinder supported by the front bracket. There is a structure in which an electromagnetic switching valve is inserted into the operating circuit of the hydraulic cylinder, and the electromagnetic switching valve is switched as the rotary leader rotates to tension the lobes during auger work and loosen the lobes during hammer work.

However, in the above device, in order to correct the slackness of the back tension rope during auger operation, a manual switching valve is inserted in series upstream of the electromagnetic switching valve in the operating circuit of the hydraulic cylinder, and the manual switching valve is operated each time. It is necessary to correct the tension in the lobe. Since this operation is frequently performed during auger work, it is extremely troublesome for the driver, and furthermore, it can cause damage to the leader due to erroneous operation, so an improvement has been desired.

[Purpose of the invention]

The present invention has been made in view of the above points, and eliminates the trouble of manually correcting the tension of the tension lobe and the danger of erroneous operation, and provides a three-point support type pile driver with high operability and safety. The purpose is to provide a tensioning device.

[Structure of the invention]

In order to achieve the above object, the present invention provides a bracket on the back side of the auger of the top sheave valve fixed to the upper end of the leader of a three-point support type pile driver, and a wire rope for pack tension is attached to the bracket. One end is connected between the leader tension bags, the other end is connected to a hydraulic cylinder which is pivoted to the freon 1~bracket, and the end of the auger wire rope is pivotally connected to the top sheave block via a load pressure gauge. An electromagnetic FJJ moss valve and a relief valve are provided in parallel in the operation circuit of the hydraulic cylinder, and a contact point of the load pressure gauge is provided in the electric circuit of the electromagnetic switching valve, so that the electromagnetic switching is performed by the operation of the load pressure gauge. It is characterized by a configuration in which the pack tension rope is tensioned by switching the valve.

〔Example〕

Embodiments of the present invention will be described in detail with reference to FIGS. 4 to 6. In the drawings, the same reference numerals as in FIGS. 1 to 3 do not indicate the same parts.

The lower part of the leader 4 is pivotally supported by the freon 1 to the bracket 3,
A top sheave block 8 is fixed on top of it.
The end 7a of the wire rope 7 is pivotally connected to the top sheave block 8, with the end 7a of the wire rope 7 hanging over the sheave 9 and the sheave 12 of the auger 11 by several lengths.

The leader tensioning device in the first invention has one racket 1 to 27 fixed on the back side of the oarge of the top sheave block 8,
Wire rope 22 for pack tension is attached to the bracket 21
One end is connected with a pin 23, and the other end is connected with a pin 27 to a rod 26 of a hydraulic cylinder 25 which is fixed to the front bracket 3 with a pin 24. Further, as shown in FIG. 5, a load pressure gauge 28 is provided at the end 7a of the wire rope 7, and a pressure switch 28a is turned on and off according to a set load.The load pressure gauge 28 is connected to the top sheave block 8. ing. The hydraulic cylinder 25 is connected to a hydraulic pump 30 via an electromagnetic switching valve 29.
A relief valve 31 is connected to the hydraulic pump 30 in parallel. Further, the pressure switch 28a of the load pressure gauge 28 is inserted into the electric circuit of the solenoid 32 of the electromagnetic switching valve 29. Note that 33 is a power source.

With the above configuration, when a load that exceeds the set value of the load pressure gauge 28, for example, the load of the auger 11 and screw 12, is applied while the auger is working, the pressure switch 28a is turned on and the electromagnetic switching valve 29 is switched via the solenoid 32. Hydraulic cylinder 2
5 is reduced and the back tension wire rope 22 is constantly pulled at the set pressure of the relief valve 31 to apply a bending force commensurate to the auger side to the leader 4. - In the leader tensioning device according to the second invention, the end 7a of the wire rope 7 is hung several lengths over the sheave 12 of the auger 11 and the sheave 9 of the top sheave block 8, as shown in FIG.
is connected to the top sheave block 8 via a load voltmeter 41, and an electromagnetic proportional relief valve 42 is provided in the hydraulic circuit of the hydraulic cylinder 25 and )+I+ pressure pump 3o. A converter 44 is provided in the electric circuit of the solenoid 43 for converting the output voltage of the load voltmeter 41 into a current value and outputting the current to the solenoid 43 of the electromagnetic proportional relief valve 42.

With the above configuration, when a load is applied to the front side of the leader during auger work, f
A current flows through the solenoid 43 of the f1l proportional relief valve 42, and the hydraulic cylinder 25 is actuated by the electromagnetic proportional relief valve 42, pulling the back tension rope 22 in proportion to the load on the auger side. Apply bending force to 2 da 4.

〔Effect of the invention〕

As mentioned above, in the first invention, Kihatsuro installed a brown on the back side of the auger of the 1-tube jeep block fixed to the upper end of the leader of a three-point support type pile driver, and attached a back tension wire to the bracket. a leader tensioning device connected to one end of the rope and connected to a hydraulic cylinder with the other end pivoted to the front bracket; and an end of the auger wire rope pivotally connected to the top sheave block via a load pressure gauge;
An electromagnetic switching valve and a relief valve are installed in parallel in the operating circuit of the hydraulic cylinder, and a contact point of the load pressure gauge is installed in the electric circuit of the electromagnetic switching valve, so that the load pressure gauge is activated. Since the back tension rope is tensioned by switching the electromagnetic switching valve, if a load that exceeds the set value on the load pressure gauge (for example, the load of the auger and screw) is applied during auger operation, the pressure switch will turn ONL and the electromagnetic switching valve will switch off. This reduces the hydraulic cylinder of the leader tensioning device and constantly pulls the back tension rope at the set pressure of the relief valve, giving the leader a bending force commensurate with the auger side. This eliminates the trouble of correcting the error and the erroneous operation.

In addition, in the second invention, the end of the wire rope for the auger is pivotally connected to the top sheave block via the load voltage h1, an electromagnetic proportional relief valve is installed in the operating circuit of the hydraulic cylinder, and the output voltage of the load voltmeter is connected to the top sheave block. A converter for converting the value into a value is installed in the electrical circuit of the electromagnetic proportional relief valve, and the output of the load voltmeter controls the electromagnetic proportional relief valve to tension the back tension rope, so that the leader's When a load is applied to the front side, a current flows from the load voltmeter to the solenoid of the electromagnetic proportional relief valve via the converter, and the hydraulic cylinder is activated by the electromagnetic proportional relief valve to adjust the back tension rope to match the load on the auger side. Since it is pulled and applies bending force to the leader, there is no need for manual operation, and it has great effects such as eliminating erroneous operations.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional three-point support type pile driver, and Figure 2 (A
), (B) are explanatory diagrams of the working position of the double-sided rotary type reader, Figure 3 (Δ), (B) are explanatory diagrams of the 1st work position of the single-sided fixed type reader, and Figure 4 is an explanatory diagram of the working position of the single-sided fixed type reader. FIG. 5 is a schematic diagram of a leader tensioning device, FIG. 5 is a hydraulic and electrical circuit diagram showing an embodiment of the first invention, and FIG. 6 is a hydraulic and electrical circuit diagram of an embodiment of the second invention. 1 is a three-point support pile driver 1, 2 is the main body, 3 is the front bracket, 4 is the leader, 5 is the back stay, 6 is the drum,
7 is a wire rope, 7a is an end of the rope, 8 is a top sheave block, 9 is a sheave, 10 is a screw, 11 is an auger, 12 is a sheave of the auger, 13 is a hammer, 21 is a bracket 1 to . 22 is a lobe for back tension, 23
．． ．． 24 is a bottle, 25 is a hydraulic cylinder, 26 is a cylinder cylinder, 27 is a bottle, 28 is a load pressure gauge, 28a is a pressure switch, 29 is an electromagnetic switching valve, 30 is a hydraulic pump, 31
32 is a relief valve, 32 is a solenoid, 33 is a power source, 41 is a load voltmeter, 42 is an electromagnetic proportional relief valve, 43 is a solenoid, and 44 is a V/A converter. Procedure amendment teeth November 6, 1981 Patent Application No. 149287 2, Title of invention Back tension device for three-point support type pile driver 3, Person making the amendment Case and relationship Patent applicant (461) Japan Vehicle Manufacturing Co., Ltd. 4, Agent 9-16 Kajicho-chome, Chiyoda-ku, Tokyo Voluntary submission 6 Number of inventions increased by amendment 7 Detailed explanation of the invention and brief explanation of the drawings in the specification subject to amendment Column 8, ? IIl Correct contents (1) "Industrial status" on page 3, line 5 of the specification was corrected to "industrial", and "from drum 6" on line 13 of the same page was corrected to "from drum to pulley 6". do. (2) In the same book, page 6, line 7, "heartless" is corrected to "extremely." (3) "12" on page 9, line 13 of the same book is corrected to "10". (4) In the third line of page 10 of the same book, ``corresponding to the auger side'' should be corrected to ``corresponding to this constant set pressure.'' (5) In the 6th line of page 11 of the same book, ``according to the load on the auger side'' was corrected to 1 with the set pressure of the electromagnetic proportional relief valve 42, and in the 7th line of the same page, ``to the leader 4'' was changed. Insert [corresponds to this set pressure]. (6) “It was worth the Ogre side” on page 12, line 12 of the same book.
is corrected to ``corresponds to this constant set pressure.'' (71 In the same book, page 13, line 9, “converter” was corrected to “converter”, and in line 12 of the same page, “according to the load on the auger side” was corrected to “at the set pressure of the electromagnetic proportional relief valve”) Then, insert "corresponding to this set pressure" after "to the leader" in the same text. (8) Correct "drum" to "pulley" in line 11, page 14 of the same book.

Claims (1)

[Claims] 1. A bracket is installed on the back side of the auger of the 1-3 jeep block fixed to the upper end of the leader of a three-point support type pile driver.
One end of the back tension m-wire A70-pu is connected to the brackets 1 to 1, and the other end is connected to a hydraulic cylinder fixed to the front bracket. 1 above
~ It is pivoted to the Jeep block, and an electromagnetic switching valve and a relief valve are provided in parallel in the operation circuit of the hydraulic cylinder, and a contact point for the load pressure if is provided in the electrical circuit of the electromagnetic switching valve to control the load Tf force. A back tension device for a three-point support type pile driver, characterized in that the back tension rope is tensioned by switching the electromagnetic switching valve according to the operation of a gauge. 2. Install a bracket on the back side of the auger of the top sheave block fixed to the top end of the leader of the three-point support type pile driver, connect one end of the back tension rope to the bracket, and connect the other end to the front bracket. A leader tension device connected to the stopped hydraulic cylinder and an electromagnetic proportional relief valve are provided in the operating circuit of the hydraulic cylinder, and the end of the auger wire rope is connected to the above 1 to 1 through the load voltmeter.
Pivotally connected to the block jeep block and load voltage h1
A converter for converting the output voltage to a current value is installed in the electric circuit of the electromagnetic proportional relief valve, and the output of the load voltmeter controls the electromagnetic proportional relief valve to tension a back tension lobe. A back tensicon device for a three-point support type pile driver.