JP5892853B2 - Hydraulic work machine - Google Patents

Description

  The present invention relates to a hydraulic working machine, and more particularly, to a hydraulic working machine that can be operated by mounting a large hydraulic working device on a small and low output hydraulic working machine.

  As a ground improvement machine which is one of hydraulic working machines, a small ground improvement machine which can work in a narrow residential area is often used. Such a small ground improvement machine is equipped with a small engine with a small output due to size restrictions. However, in recent years, it has been desired to increase the efficiency of ground improvement work by using a working device with a large output as much as possible, for example, a large auger, even if it is a small ground improvement machine.

  Therefore, it is possible to drive a large auger by preparing a hydraulic unit with a large output outside the ground improvement machine and supplying hydraulic oil from this high output hydraulic unit to a small ground improvement machine. It becomes. When supplying hydraulic oil from an external hydraulic unit to a small ground improvement machine, an appropriate hydraulic path of the external hydraulic unit and an appropriate hydraulic path provided in the small ground improvement machine are connected via a hydraulic hose. (See, for example, Patent Document 1).

JP 2010-180539 A

  However, in general, since the operation of the hydraulic unit is performed on a panel surface arranged in the hydraulic unit itself, it is necessary to move each time the operation is performed. It is also possible to place a remote control for operating the external hydraulic unit in the cab of the ground improvement machine, and to operate the external hydraulic unit with the remote control. Etc., and there is a possibility that the operation becomes complicated and an erroneous operation occurs. In addition, the low output hydraulic unit mounted on the ground improvement machine and the external high output hydraulic unit differ in the amount of oil during idling. Delicate inching may be difficult.

  Therefore, the present invention can efficiently operate a large work apparatus by supplying hydraulic oil from an external high-power hydraulic unit, and also keeps a good feeling of operation of delicate work such as inching. It aims at providing the hydraulic working machine which can do.

  In order to achieve the above object, a hydraulic working machine of the present invention includes a working machine main body provided with a hydraulic working device, and an external hydraulic unit connected to the working machine main body via a detachable hydraulic hose, The work machine body includes an internal hydraulic unit provided in the work machine body, an operation control unit that controls an operation state of the hydraulic work device, and the internal hydraulic pressure based on an operation signal transmitted from the operation control unit. An internal control valve that controls the flow of hydraulic fluid supplied from the unit to the working device, a path for supplying hydraulic fluid to the working device, a path for the internal hydraulic fluid supplied from the internal hydraulic unit, and a hydraulic pressure from the external hydraulic unit A hydraulic oil supply path switching unit that switches to a path of an external hydraulic oil supplied via a hose, and a hydraulic unit that supplies hydraulic oil to the working device include an internal hydraulic unit or an external hydraulic unit. A hydraulic unit changeover switch for switching to an external hydraulic unit, and an operational signal output unit for cutting off an operational signal transmitted from the operation control unit to the internal control valve and transmitting the operational signal to the external hydraulic unit. Has a maximum output greater than the maximum output of the internal hydraulic unit provided in the work implement main body, and a hydraulic pump driven by an engine, and the hydraulic pump to the work device via the hydraulic hose. An external control valve for controlling the flow of hydraulic oil to be supplied, an operation signal relay means for operating the external control valve based on an operation signal from the operation signal output unit, and a discharge amount at idling of the external hydraulic unit. The flow rate adjusting means is set to be equal to the discharge amount when idling the internal hydraulic unit.

  Furthermore, in the hydraulic working machine according to the present invention, the hydraulic pump provided in the external hydraulic unit is a variable displacement pump, and when the engine of the external hydraulic unit is switched to an idling state, the discharge of the variable displacement pump is performed. When the external control valve switches the engine of the external hydraulic unit to the idling state, the capacity control means for adjusting the amount to be equal to the discharge amount during idling of the internal hydraulic unit, the external control valve It is characterized by comprising valve opening restriction means for setting the flow rate of hydraulic oil supplied to the working device via a hydraulic hose to be equal to the discharge amount during idling of the internal hydraulic unit.

  The operation signal transmitted from the operation control unit to the internal control valve is a hydraulic signal, and the operation signal transmitted from the operation signal output unit to the external hydraulic unit is based on a pressure change of the hydraulic signal. The operation signal relay means is a control valve that is actuated by the electric signal.

  According to the hydraulic working machine of the present invention, the external hydraulic unit can be operated by the operation of the operation control unit provided in the working machine body, and a large working device can be operated without impairing operability. it can. Further, by setting the discharge amount during idling equally between the internal hydraulic unit and the external hydraulic unit, the operational feeling during inching can be kept the same as when the external hydraulic unit is not used. Furthermore, when using the external hydraulic unit, the operation signal transmitted from the operation control unit to the internal control valve is cut off, thereby reducing the burden on the internal hydraulic unit.

It is a hydraulic circuit diagram of the principal part which shows one form example of the hydraulic working machine of this invention. It is a schematic block diagram which shows an example of the whole structure of the hydraulic circuit in the hydraulic working machine of this invention. It is explanatory drawing which shows the other example of a hydraulic oil supply path | route switching part. It is a front view which shows the state which connected the external hydraulic unit to the small ground improvement machine. It is also a plan view.

  This embodiment shows an example of a state in which hydraulic oil is supplied from a high-output external hydraulic unit to a ground improvement machine, which is one of hydraulic working machines, and an auger that is a hydraulic working device is rotationally driven.

  First, as shown in FIGS. 4 and 5, the ground improvement machine 11 serving as a work machine body includes a lower traveling body 12 having a pair of left and right crawlers, and an upper portion provided on the lower traveling body 12 so as to be turnable. A revolving unit 13, a leader 14 provided in a front portion of the upper revolving unit 13, a raising / lowering cylinder 15 supporting the leader 14 from the rear, and a hydraulic working device provided in the leader 14 so as to be movable up and down. A certain rotational drive device (auger) 16, an elevating device 17 for raising and lowering the auger 16 via an elevating chain, an cab 18 provided in the upper swing body 13, a hydraulic unit (internal hydraulic unit), a generator, and the like And an equipment room 19 in which is stored. Also, a pair of front jacks 13 a are provided on the front left and right of the upper swing body 13, and a pair of rear jacks 13 b are provided on the left and right sides of the upper swing body 13. A winch (not shown) is provided on the upper surface of the front of the upper swing body 13. Is provided.

  The ground improvement machine 11 is equipped with an excavating head 21 having an excavating blade 21a and a stirring blade 21b at the lower end, and rotating the hollow rod 23 having an swivel joint 22 at the upper end with the auger 16 while the auger 16 The ground is improved by injecting the ground improver supplied through the swivel joint 22 into the ground from the excavation head 21.

  The external hydraulic unit 51 includes an engine 52, a hydraulic pump 53 driven by the engine 52, and the like in a casing 54 having a soundproof structure. The external hydraulic unit 51 includes the ground improvement machine. 11 having a maximum output that is larger than the maximum output of the internal hydraulic unit mounted in 11, for example, about twice the maximum output is preferably used. Such a hydraulic circuit of the external hydraulic unit 51 and the hydraulic circuit provided in the ground improvement machine 11 can be attached and detached by a pair of hydraulic hoses 55 on the feeding side and the returning side having self-sealing couplings at both ends. It is formed so that it can be connected.

  As shown in FIG. 2, the internal hydraulic unit 30 housed in the equipment room 19 of the ground improvement machine 11 includes a plurality of hydraulic pumps 32 driven by an engine 31 and hydraulic oil discharged from each hydraulic pump 32. An operation control unit 33 having a plurality of control valves for controlling the flow and a plurality of hydraulic pipes for connecting the respective devices are provided, and the operation levers, pedals, and the like provided in the cab 18 are operated according to the operation state. Each control valve is actuated to drive a hydraulic motor 12M for driving the left and right crawlers of the lower traveling body 12, a hydraulic motor 13M for rotating the upper revolving body 13, a hydraulic cylinder 15S for extending and retracting the hoisting cylinder 15, A hydraulic cylinder 13S for extending and contracting the jack 13a and the rear jack 13b, an auger rotating hydraulic motor 16M for rotating the auger 16; Elevating hydraulic motor 17M for driving the descending device 17, such as a hydraulic motor 20M winch drive, it supplies the hydraulic oil ejected from the hydraulic pump 32, respectively. The internal hydraulic unit 30 is formed so that a part of the operation control unit 33 can be controlled by the remote controller 34.

  Among these hydraulic cylinders and hydraulic motors, a motor-side path 35 connected to the auger rotating hydraulic motor 16M is a hydraulic path for supplying hydraulic oil to the auger rotating hydraulic motor 16M that requires the greatest output. Hydraulic oil supply path for switching the path for supplying hydraulic oil to the internal path 36 for supplying internal hydraulic oil from the internal hydraulic unit 30 and the external path 56 for supplying external hydraulic oil from the external hydraulic unit 51 A switching unit 37 is provided.

  As shown in FIG. 2, the hydraulic oil supply path switching unit 37 has self-sealing couplings 35 a, 36 a, and 56 a attached to the respective ends of the motor side path 35, the internal side path 36, and the external side path 56. The self-sealing coupling 35a of the motor-side hydraulic path 35 is connected to either the self-sealing coupling 36a of the inner-side path 36 or the self-sealing coupling 56a of the outer-side path 56 via a hydraulic hose. The hydraulic oil supply source may be set to the internal side or the external side. As shown in FIG. 3, the path communicating with the motor side hydraulic path 35 is divided into an internal path 36 and an external path 56. A switchable direction switching valve 38 may be provided, and the hydraulic oil supply source may be set to the internal side or the external side by switching the direction switching valve 38.

  When the supply source of the hydraulic oil supplied to the auger rotating hydraulic motor 16M is switched to the external hydraulic unit 51 by the hydraulic oil supply path switching unit 37, the external hydraulic oil discharged from the hydraulic pump 53 driven by the engine 52 is In a state in which the flow is controlled by the external control valve 57, the external side passage 56 including the hydraulic hose 55 is supplied to the motor side passage 35 to rotationally drive the auger rotating hydraulic motor 16M.

  Next, a circuit configuration in which the flow of hydraulic oil supplied from the external hydraulic unit 51 to the auger rotating hydraulic motor 16M can be controlled by an operation lever provided in the cab 18 of the ground improvement machine 11 based on FIG. Will be explained. In the following description, the same components as those of the ground improvement machine 11, the internal hydraulic unit 30 and the external hydraulic unit 51 shown in FIGS. Omitted.

  First, in the internal hydraulic unit 30, the hydraulic circuit from the hydraulic pump 32 that supplies the hydraulic oil to the auger rotating hydraulic motor 16M includes the hydraulic cylinder 15S for expanding and contracting the undulating cylinder 15 and the hydraulic oil for one traveling hydraulic motor 12M. A hydraulic circuit to supply is included. In the discharge path 32a of the hydraulic pump 32, a travel control valve 12C that operates the travel hydraulic motor 12M via a relief valve 32b, an auger control valve 16C that operates the auger rotation hydraulic motor 16M, and a hydraulic cylinder 15S. And a relief control valve 15C for actuating the. The cab 18 is provided with a travel lever 12L for operating the travel control valve 12C in the forward or reverse direction, and controls the flow of pilot hydraulic oil supplied from the pilot pump 32P to control the auger An auger pilot valve 16P and a hoisting pilot valve 15P for operating the control valve 16C and the hoisting control valve 15C are provided.

  Furthermore, in order to switch the supply source of the hydraulic oil supplied to the auger rotating hydraulic motor 16M to the internal hydraulic unit 30 and the external hydraulic unit 51, in addition to the hydraulic oil supply path switching unit 37, the auger pilot valve 16P The forward rotation pilot path 16N and the reverse rotation pilot path 16R connected to the auger control valve 16C include pressure detectors 41N and 41R that detect pressures in the paths 16N and 16R, and blocking that blocks the paths 16N and 16R. Valves 42N and 42R are provided, respectively, and a hydraulic unit changeover switch 43 is provided. The hydraulic unit changeover switch 43 turns on / off an electric signal for electrically opening and closing the shutoff valves 42N and 42R and an electric signal for controlling the engine 52 of the external hydraulic unit 51.

  The shutoff valves 42N and 42R open the flow path when the hydraulic unit changeover switch 43 is set to the internal side (OFF), and shut off the flow path when the hydraulic unit changeover switch 43 is set to the external side (ON). Operate. The pressure detectors 41N and 41R serve as an operation signal output unit for transmitting the operation signal of the internal hydraulic unit 30 to the external hydraulic unit 51, and the pressure change of the pilot hydraulic oil in the paths 16N and 16R. The generated electric signal is transmitted as an operation signal to the external pilot valve 58 which is an operation signal relay means provided in the external hydraulic unit 51.

  When performing ground improvement work using the ground improvement machine 11 alone without using the external hydraulic unit 51, the motor side path 35 is connected to the internal side path 36 to connect the hydraulic oil supply path switching unit 37. Is set to the inner side, and the hydraulic unit changeover switch 43 is set to the inner side (OFF). In this state, for example, when the hoisting pilot valve 15P is operated to the expansion side or the contraction side by the hoisting operation lever, a hydraulic signal as an operation signal composed of the pressure of the pilot hydraulic fluid is generated from the hoisting pilot valve 15P. The undulation control valve 15C is actuated by a predetermined amount in a predetermined direction in accordance with the direction and pressure of the hydraulic signal, and the hydraulic oil from the hydraulic pump 32 is supplied to the expansion side or contraction side of the hydraulic cylinder 15S. The cylinder 15 is expanded and contracted.

  Further, when the auger pilot valve 16P is operated, for example, to the forward rotation side by operating the operation lever, the shutoff valve 42N is in an open state, so that the auger pilot valve 16P is passed through the forward rotation pilot path 16N. A forward hydraulic signal is transmitted to the control valve 16C, the auger control valve 16C operates in the forward direction based on the hydraulic signal, and hydraulic oil (internal hydraulic oil) from the hydraulic pump 32 is supplied to the auger control valve. 16C is supplied to the forward rotation side of the auger rotating hydraulic motor 16M via the internal side path 36 and the motor side path 35, and the auger 16 is rotationally driven in the forward direction.

  The auger pilot valve 16P is configured to transmit an amount of pilot hydraulic oil corresponding to the operation amount of the operation lever as a hydraulic signal to the auger control valve 16C. The pressure of the hydraulic signal transmitted from the pilot valve 16P to the auger control valve 16C increases, and the amount of operation of the auger control valve 16C increases, so that the auger rotation hydraulic motor passes from the hydraulic pump 32 through the auger control valve 16C. Since the flow rate of the hydraulic oil supplied to 16M increases, the auger rotating hydraulic motor 16M can be rotated at high speed.

  When the large auger 16 is driven by hydraulic oil from the high output external hydraulic unit 51, the motor side path 35 is connected to the external side path 56 to switch the hydraulic oil supply path switching unit 37 to the outside. Then, the hydraulic unit changeover switch 43 is switched to the outside (ON) to close the shutoff valves 42N and 42R. When the operation lever of the auger pilot valve 16P is operated in this state, for example, when the pilot hydraulic oil is supplied from the auger pilot valve 16P to the normal rotation pilot path 16N by tilting the operation lever to the normal rotation side, the normal rotation pilot path Since the pressure in 16N rises, an electrical signal corresponding to the pressure rise is transmitted from the pressure detector 41N to the external pilot valve 58, and the external pilot valve 58 operates in the forward direction according to the magnitude of the electrical signal, Pilot hydraulic oil supplied from a pilot pump 53P provided in the external hydraulic unit 51 is supplied as an operation signal for operating the external control valve 57 hydraulically.

  As a result, the hydraulic oil (external hydraulic oil) discharged to the discharge path 53a of the hydraulic pump 53 passes through the external path 56 including the hydraulic hose 55 via the external control valve 57, and the motor side path 35 on the forward rotation side. Is supplied to the forward rotation side of the auger rotating hydraulic motor 16M, and the auger 16 rotates the hollow rod 23 in the forward direction. When the auger 16 is rotated in the reverse direction, the pressure detector 41R converts the pressure increase in the reverse pilot path 16R into an electric signal by operating the operating lever of the auger pilot valve 16P in the reverse direction, and the external pilot. By transmitting to the valve 58, the external control valve 57 is operated in the reverse direction, and the auger 16 is rotated in the reverse direction.

  Therefore, even when the external hydraulic unit 51 is used, the operation lever of the auger pilot valve 16P provided in the cab 18 is used only by the ground improvement machine 11 without using the external hydraulic unit 51, and the internal hydraulic unit 30. The hydraulic oil from the external hydraulic unit 51 can be supplied to the auger 16 by performing the same operation as when hydraulic oil is supplied from the hydraulic oil source. Thereby, the large auger 16 can be driven by the hydraulic oil from the external hydraulic unit 51 having a larger output than the internal hydraulic unit 30 without impairing the operability, and the ground improvement work by the ground improvement machine 11 is efficient. Can be done well.

  Furthermore, since the forward rotation pilot path 16N and the reverse rotation pilot path 16R are blocked by the shutoff valves 42N and 42R, the auger control valve 16C does not operate and the hydraulic oil of the internal hydraulic unit 30 is supplied to the internal side path 36. As a result, the pressure in the internal path 36 does not increase, so that the load on the internal hydraulic unit 30 can be reduced and the equipment can be protected. It can be used effectively for the motor 17M and the like.

  Further, the external hydraulic unit 51 has a discharge amount of hydraulic oil to the external path 56 when the operation changeover switch 61 provided in the operation control unit of the engine 52 is switched to the idling position 61a and the engine 52 is in an idling state. In addition, a flow rate adjusting means for setting the discharge amount to the internal side path 36 when the engine 31 of the internal hydraulic unit 30 is in an idling state is provided.

  First, the first flow rate adjusting means shown in the present embodiment uses a variable displacement pump, for example, a swash plate type variable displacement pump, for the hydraulic pump 53, and when the operation changeover switch 61 is switched to the idling position 61a, the displacement The amount of hydraulic oil discharged from the hydraulic pump 53 to the discharge path 53a is adjusted by electrically operating the swash plate angle control unit 62 as control means to adjust the angle of the swash plate. When the engine 31 is in an idling state, the hydraulic oil is set to be equal to the amount of hydraulic oil discharged from the hydraulic pump 32 to the discharge path 32a.

  When the hydraulic pump 53 is a fixed displacement pump, the second flow rate adjusting means electrically operates the valve opening degree restricting means 63 when the operation changeover switch 61 is switched to the idling position 61a to perform external control. By restricting the maximum valve opening degree of the valve 57, the amount of hydraulic oil that passes through the external control valve 57 and is discharged to the external path 56 is reduced to the internal side when the engine 31 of the internal hydraulic unit 30 is in the idling state. The amount of hydraulic oil discharged to the path 36 is set to be equal to the amount of hydraulic oil, and excess hydraulic oil is returned from the relief valve 53b.

  By providing such a flow rate adjusting means in the external hydraulic unit 51, the flow rate of the hydraulic oil supplied from the external hydraulic unit 51 to the auger 16 during idling can be changed to that of the hydraulic oil supplied from the internal hydraulic unit 30 during idling. It can be set to the same flow rate and does not impair the operation feeling of the inching work that is performed by finely operating the operation lever during idling, so that inching is easy even when using the external hydraulic unit 51 And it can be done reliably.

  In the hydraulic circuit diagram shown in FIG. 1, both the first flow rate adjusting unit and the second flow rate adjusting unit are described as the flow rate adjusting unit, but either one of the flow rate adjusting units is appropriately selected. Can be adopted. Further, the external pilot valve 58 and the external control valve 57 can be electrically controlled to adjust the flow rate.

  Further, the operation changeover switch 61 shown in the present embodiment is capable of adjusting the rotational speed of the engine 31 in accordance with the capability of the hydraulic working device such as the auger 16 that supplies hydraulic oil from the external hydraulic unit 51. In addition, although the medium speed position 61b and the high speed position 61c are provided, it can be formed by two-stage switching between the idling position 61a and the normal operation position.

  Furthermore, in this embodiment, the example in which the present invention is applied to a small ground improvement machine for performing ground improvement work in a narrow residential area or the like has been shown. Can also be applied in the same manner.

  DESCRIPTION OF SYMBOLS 11 ... Ground improvement machine, 12 ... Lower traveling body, 12C ... Traveling control valve, 12L ... Traveling lever, 12M ... Traveling hydraulic motor, 13 ... Upper turning body, 13M ... Turning hydraulic motor, 13S ... Hydraulic cylinder, 13a ... front jack, 13b ... rear jack, 14 ... leader, 15 ... hoisting cylinder, 15C ... hoisting control valve, 15P ... hoisting pilot valve, 15S ... hydraulic cylinder, 16 ... rotary drive device (auger), 16C ... auger Control valve, 16M ... auger rotation hydraulic motor, 16N ... forward rotation pilot path, 16P ... auger pilot valve, 16R ... reverse rotation pilot path, 17 ... lifting device, 17M ... lifting hydraulic motor, 18 ... cab DESCRIPTION OF SYMBOLS 19 ... Equipment room, 20M ... Hydraulic motor for winch drive, 21 ... Excavation head, 21a ... Excavation blade, 21b ... Agitation blade, 22 ... 23 ... Hollow rod, 30 ... Internal hydraulic unit, 31 ... Engine, 32 ... Hydraulic pump, 32P ... Pilot pump, 32a ... Discharge path, 32b ... Relief valve, 33 ... Operation control unit, 34 ... Remote control, 35 ... Motor side path, 35a ... Self seal coupling, 36 ... Internal side path, 36a ... Self seal coupling, 37 ... Hydraulic oil supply path switching unit, 38 ... Direction switching valve, 41N, 41R ... Pressure detector, 42N, 42R DESCRIPTION OF SYMBOLS ... Shutoff valve, 43 ... Hydraulic unit changeover switch, 51 ... External hydraulic unit, 52 ... Engine, 53 ... Hydraulic pump, 53P ... Pilot pump, 53a ... Discharge path, 53b ... Relief valve, 54 ... Casing, 55 ... Hydraulic hose, 56 ... External side path, 56a ... Self-seal coupling, 57 ... External control valve, 58 ... External path Lot valve, 61 ... operation switching switch, 61a ... idle position, 61b ... medium speed position, 61c ... speed position, 62 ... swash plate angle control unit, 63 ... valve opening regulating means

Claims (4)

  A working machine body including a hydraulic working device; and an external hydraulic unit connected to the working machine body via a hydraulic hose that can be attached to and detached from the working machine body, wherein the working machine body includes an internal hydraulic pressure provided in the working machine body. An internal control unit that controls the flow of hydraulic oil supplied from the internal hydraulic unit to the work device based on an operation signal transmitted from the operation control unit. An operation for switching a control valve and a path for supplying hydraulic oil to the working device between an internal hydraulic oil path supplied from an internal hydraulic unit and an external hydraulic oil path supplied from the external hydraulic unit via a hydraulic hose. An oil supply path switching unit, a hydraulic unit switching switch for switching a hydraulic unit that supplies hydraulic oil to the working device to an internal hydraulic unit or an external hydraulic unit, and the operation An operation signal output unit that cuts off an operation signal transmitted from the control unit to the internal control valve and transmits the operation signal to the external hydraulic unit, and the external hydraulic unit is provided in the work implement body. A hydraulic pump that has a maximum output that is greater than the maximum output of the internal hydraulic unit, and that controls the flow of hydraulic oil supplied from the hydraulic pump to the working device via the hydraulic hose. A control valve, an operation signal relay means for operating the external control valve based on an operation signal from the operation signal output unit, and a discharge amount at idling of the external hydraulic unit, a discharge amount at idling of the internal hydraulic unit. A hydraulic working machine comprising flow rate adjusting means that is set equal to the amount.   The hydraulic pump provided in the external hydraulic unit is a variable displacement pump, and when the engine of the external hydraulic unit is switched to the idling state, the discharge amount of the variable displacement pump is the discharge during idling of the internal hydraulic unit. 2. The hydraulic working machine according to claim 1, further comprising a capacity control means for adjusting the amount to be equal to the amount.   When the engine of the external hydraulic unit is switched to an idling state, the external control valve supplies a flow rate of hydraulic oil supplied from the external control valve to the working device via the hydraulic hose when the internal hydraulic unit is idling. The hydraulic working machine according to claim 1, further comprising valve opening restriction means for setting the discharge amount to be equal to the discharge amount.   The operation signal transmitted from the operation control unit to the internal control valve is a hydraulic signal, and the operation signal transmitted from the operation signal output unit to the external hydraulic unit is based on a change in pressure of the hydraulic signal. The hydraulic working machine according to any one of claims 1 to 3, wherein the operation signal relay means is a control valve that is output from a pressure detector that generates a signal and is operated by the electric signal.

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