JPH11336456A - Auger driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an auger driving device having large excavation capacity in spite of small size. SOLUTION: The auger driving device has an electric motor 32 and a hydraulic motor 36 simultaneously driving an auger screw 14 while having a pressure control valve 56 controlling hydraulic-fluid pressure fed to the hydraulic motor 36. An electromagnetic proportional pressure control valve is used as the pressure control valve 56, and the auger driving device has a control circuit 62 controlling the above-mentioned electromagnetic proportional pressure control valve in response to the load of the electric motor 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auger driving device which is moved up and down along a guide rail of a leader, and rotates and drives an auger screw to excavate a pile hole.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a self-propelled pile construction machine 1 is known, and a pile construction machine 1 includes a leader 2
Are supported by the stay 4 and the catching fork 6 so as to be able to be turned upside down. A pair of elongated guide rails 8 are laid on the front surface of the reader 2 along the longitudinal direction.

The guide rail 8 has a plurality of guide givers 1.
The auger driving device 12 is slidably mounted via the first auger driving device. An auger screw 14 is attached to the auger driving device 12, and is configured to rotate the auger screw 14 by a motor (not shown) mounted thereon. An electric motor or a hydraulic motor is used as the motor.

[0006] A winch 16 is mounted on the pile construction machine 1, and a wire 18 pulled out from the winch 16 is
It is pulled out along the leader 2 and is suspended over a sheave 22 rotatably supported at the upper end of the reader 2 via a sheave 20 rotatably supported in the middle of the reader 2.

Further, after the wire 18 is wound around the sheave 24 provided at the upper end of the reader 2, the wire 1
The auger driving device 12 is suspended from the device 8, and the auger driving device 12 can be moved up and down along the reader 2 by driving the winch 16.

[0006]

However, in such a conventional device, when an electric motor is used as the motor,
Although a large excavating ability can be obtained, the inching performance is inferior to the hydraulic motor, and the weight of the electric motor increases,
There was a problem that the stability of the pile construction machine deteriorated.

When a hydraulic motor is used, the hydraulic pump can be driven by the engine of the pile construction machine and hydraulic oil can be supplied from the hydraulic pump. A generator must be provided. On the other hand, when a generator is used, the engine of the pile construction machine only drives the winch, and there is a problem that the surplus of the engine capacity is large.

[0008] An object of the present invention is to provide an auger driving device having a large excavating ability even if it is small.

[0009]

In order to achieve the above object, the present invention takes the following means to solve the problem. That is, in an auger driving device that moves up and down along a guide rail of an upright reader and rotationally drives an auger screw, an electric motor and a hydraulic motor that simultaneously drive the auger screw are provided, and supplied to the hydraulic motor. This is an auger drive device provided with a pressure control valve for controlling operating hydraulic pressure.

[0010] The pressure control valve may be an electromagnetic proportional pressure control valve, and may be provided with a control circuit for controlling the electromagnetic proportional pressure control valve according to the load of the electric motor.
Alternatively, hydraulic oil may be supplied to the hydraulic motor from a hydraulic pump driven by an engine of the pile construction machine. Further, the electric motor may be connected to a generator.

Further, the electromagnetic proportional pressure control valve may be an electromagnetic proportional pressure relief valve, or the electromagnetic proportional pressure control valve comprises a pilot operated relief valve and an electromagnetic proportional pressure reducing valve, The pilot pressure reduced by the valve may be introduced into the pilot operation relief valve.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, the auger screw 14 is connected to a large gear 26,
A pair of pinion gears 28 and 30 are meshed with 6. One pinion gear 28 is attached to a speed reducer 34 connected to an electric motor 32, and the other pinion gear 30 is connected to a speed reducer 38 connected to a hydraulic motor 36.
Attached to.

The hydraulic motor 36 has a pair of supply / discharge passages 40,
42 are connected, and the supply / discharge passages 40 and 42 are connected to the switching valve 4.
4 is connected. The switching valve 44 is connected to a hydraulic pump 48 via a main flow path 46 and to a tank 52 via a return flow path 50. The hydraulic pump 48 is connected so as to be driven by the engine 54 of the pile construction machine 1.

A switching valve 44 connects a main flow path 46 to one supply / discharge flow path 40 and a normal rotation position 44a that connects a return flow path 50 to the other supply / discharge flow path 42. 40,
A stop position 44b communicating the return passage 50 with the return passage 50, and a reverse rotation position 44 communicating the main passage 46 with the other supply / discharge passage 42 and the return passage 50 and the one supply / discharge passage 40.
c.

The main flow passage 46 is connected to the tank 52 via a pressure control valve 56. In the present embodiment, an electromagnetic proportional relief valve is used as the pressure control valve 56, and the relief pressure is set according to an excitation signal input to the electromagnetic proportional relief valve. Therefore, the main flow path 46 is controlled to be equal to or lower than the relief pressure.

On the other hand, the electric motor 32 is connected to a generator 58, and a load detection sensor 60 for detecting a current value inputted to the electric motor 32 is provided. The current value detected by the load detection sensor 60 is
The control circuit 62 outputs an excitation signal to the pressure control valve 56 in accordance with the current value. The current value of the electric motor 32 is proportional to the load. When the load is large, the pressure control valve 56 is controlled so that the relief pressure increases.

The reduction ratio is set so that the rotation speed of the pinion gear 30 which is the output of the hydraulic motor 36 is always higher than the rotation speed of the pinion gear 28 which is the output of the electric motor 32. This allows the hydraulic motor 3
6 always rotates in the relief state. When the load of the auger screw 14 is small, the set relief pressure of the pressure control valve 56 is reduced to reduce the energy loss of the engine 54,
Reduce the amount of heat generated. By increasing the set relief pressure of the pressure control valve 56 in proportion to the current value of the electric motor 32, the excavating force of the auger screw 14 can be efficiently generated.

Next, the operation of the above-described auger drive device of the present embodiment will be described. First, auger screw 1
When the rotary 4 is driven, the hydraulic pump 48 is driven by the engine 54 to supply hydraulic oil to the main flow path 46. When the auger screw 14 is rotated forward, the switching valve 44
Is switched to the normal rotation position 44a, hydraulic fluid is supplied to the hydraulic motor 36 via the supply / discharge flow path 40, and the hydraulic oil is returned to the tank 52 via the supply / discharge flow path 42 and the return flow path 50.

Therefore, the hydraulic motor 36 has a speed reducer 38,
A torque for driving the auger screw 14 through the pinion gear 30 and the large gear 26 is generated. The torque is proportional to the supplied operating oil pressure, and when the operating oil pressure in the main flow path 46 exceeds the relief pressure set by the pressure control valve 56, the pressure control valve 56 opens to release the operating oil to the tank 52.

When the operating oil pressure of the main passage 46 rises to the relief pressure, a torque corresponding to the relief pressure is applied to the auger screw 14. When the electric motor 32 is driven at the same time, in addition to the torque by the hydraulic motor 36, the torque by the electric motor 32 is further applied to the auger screw 14 via the reduction gear 34, the pinion gear 28, and the large gear 26. Thereby, the auger screw 14 is given a sufficient torque against the digging resistance, and digging is performed by the auger screw 14.

When the excavation resistance is large and the load applied to the electric motor 32 is large, the current value of the electric motor 32 is large, the load detection sensor 60 detects this current value, and the control circuit 62 responds to this current value. An excitation signal is output so that the relief pressure of the pressure control valve 56 increases. When the relief pressure increases, the torque by the hydraulic motor 36 increases, and the hydraulic motor 36 assists in increasing the excavation resistance.

As described above, by simultaneously driving the auger screw 14 by the hydraulic motor 36 and the electric motor 32, a large excavating ability can be obtained,
The hydraulic motor 36 is very small in comparison with the electric motor 32, and the electric motor 32 may have a small capacity as much as the hydraulic motor 36 assists, so that the auger driving device can be downsized.

Next, an auger driving apparatus according to a second embodiment different from the above-described embodiment will be described with reference to FIG.
The same members as those described above are denoted by the same reference numerals, and detailed description is omitted. In the second embodiment, the main flow path 46
And the tank 52 are connected via a pilot operation relief valve 70, and the pilot operation relief valve 70 is connected so that pilot pressure from the electromagnetic proportional pressure reducing valve 72 can be introduced. The electromagnetic proportional pressure reducing valve 72 reduces the operating oil pressure supplied from the hydraulic pump 74 in accordance with the input excitation signal and supplies it to the pilot operation relief valve 70. The electromagnetic proportional pressure reducing valve 72 is connected so that an excitation signal corresponding to a load can be input from the control circuit 62 in the same manner as described above.

According to the auger driving device of the second embodiment, the relief pressure of the main flow passage 46 can be changed in accordance with the load of the electric motor 32 and the output torque of the hydraulic motor 36 can be changed as in the above-described embodiment. . The hydraulic pump 74
A relief valve 76 is connected to the discharge side of the valve.

As described above, the present invention is not limited to such embodiments at all, and can be implemented in various modes without departing from the gist of the present invention.

[0026]

As described above in detail, the auger drive device of the present invention drives the auger screw to rotate simultaneously by the hydraulic motor and the electric motor, so that the capacity of the electric motor can be reduced by that amount and the overall size can be reduced. It has the effect that it can be converted. In addition, the generator connected to the electric motor can be reduced in size, and energy can be used without waste. Furthermore, by controlling the pressure control valve according to the load of the electric motor, it is possible to automatically increase the torque of the hydraulic motor in response to load fluctuations, and to efficiently use the output of the engine of the pile construction machine for excavation. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an auger driving device as one embodiment of the present invention.

FIG. 2 is a hydraulic circuit diagram of a pressure control valve according to a second embodiment.

FIG. 3 is a side view of a conventional pile construction machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pile construction machine 2 ... Leader 12 ... Auger drive device 14 ... Auger screw 32 ... Electric motor 36 ... Hydraulic motor 44 ... Switching valve 46 ... Main flow path 48 ... Hydraulic pump 56 ... Pressure control valve 60 ... Load detection sensor 62 ... Control circuit

Claims (6)

[Claims] 1. An auger driving device which is moved up and down along a guide rail of an erect leader and rotationally drives an auger screw, comprising: an electric motor and a hydraulic motor for simultaneously driving the auger screw; An auger drive device comprising a pressure control valve for controlling a working oil pressure supplied to the auger. 2. The pressure control valve according to claim 1, wherein the pressure control valve is an electromagnetic proportional pressure control valve, and the control circuit controls the electromagnetic proportional pressure control valve according to a load of the electric motor. Auger drive. 3. The auger drive device according to claim 1, wherein hydraulic oil is supplied to the hydraulic motor from a hydraulic pump driven by an engine of the pile construction machine. 4. The auger drive device according to claim 1, wherein the electric motor is connected to a generator. 5. The auger drive device according to claim 2, wherein the electromagnetic proportional pressure control valve is an electromagnetic proportional relief valve. 6. The electromagnetic proportional pressure control valve comprises a pilot operated relief valve and an electromagnetic proportional pressure reducing valve, and introduces a pilot pressure reduced by the electromagnetic proportional pressure reducing valve to the pilot operated relief valve. 5. The auger driving device according to claim 2, wherein