JPS5847531B2 - soukou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention, for example, is a wheel loader/backhoe, in which a traveling type work device and a stationary type work device are installed at the front and rear of the machine, and the machine is driven by an engine using a mechanical transmission device. The present invention relates to a driving device for a construction machine of a traveling and stable combination type, in which a hydraulic pump can be driven, and each working device is driven by each hydraulic device to which pressure oil is supplied from the hydraulic pump.

For example, in the case of a wheel loader and backhoe, it is generally set so that 50% or more of the engine output is consumed for driving the machine during loading work, and the remaining 50% or less is used for the work of the loading device. The hydraulic pump that drives the loading device is configured to output less than 50% of its remaining output.

Conventionally, the set pressure of the hydraulic circuit of the loading device and the set pressure of the hydraulic circuit of the excavation equipment were set to the same pressure, so when excavating with a backhoe using the hydraulic pump,
Although the engine has surplus power when the machine is not moving, this surplus power cannot be used to drive the hydraulic pump, and excavation work can only be performed with less than 50% of the engine's output. There were drawbacks.

The present invention enables excavation work (stationary work) to be performed using the full output of the engine by making it possible to use the remaining power of the engine to drive one hydraulic pump during excavation work (stationary work).

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 shows a side view of the shovel loader and backhoe.
This machine 1 is equipped with a loading device 2 at the front, and an excavation device 3 detachably attached to the rear via a coupling device 4.

The engine 5 mounted on the machine 1 is configured to drive a pair of left and right crawlers T via a mechanical transmission device 6, and also to drive one hydraulic pump 8.

This hydraulic pump 8 hydraulically drives the loading device 2 and the excavating device 3, and its hydraulic circuit is structured as shown in FIG.

That is, the hydraulic pressure of the hydraulic pump 8 is transmitted through the circuit 12 of the control valve block 11 of the excavation rig 3 and the control valve block 90 of the loading device 2.
It is designed to be supplied in series with the circuit 10.

Both relief valves 16 are set such that the set pressure of the relief valve 17 of the hydraulic circuit 12 on the excavation equipment 3 side is considerably higher than the set pressure of the relief valve 16 of the hydraulic circuit 9 on the loading equipment 2 side.
・The pressure is set to 17.

For example, the loading side relief valve 16 is 140 kg/d.
In that case, the excavation side relief valve 17 is set to 180 kg/cnf.

As a result, when the hydraulic pressure of the pump 8 drives the loading device 2, the maximum power consumption of the pump 8 is 50% of the engine output because the set pressure of the relief valve 16 of the loading device side hydraulic circuit 10 is low. As shown below, when the pressure oil of the pump 8 drives the drilling rig 3, the maximum power consumption of the pump 8 is the maximum power consumption of the engine 5 because the set pressure of the relief valve 17 of the hydraulic port passage 12 on the drilling rig side is high. Close to full output.

In the figure, reference numerals 18 and 19 indicate self-sealing pipe joints, which allow the excavation equipment side hydraulic circuit 12 to connect and separate from the oil feed path 20 of the hydraulic pump 8 and the loading equipment side hydraulic circuit 10. It is now possible.

When this separation is performed, the oil feed path 2 of the hydraulic pump 8
The hydraulic circuit 10 of the zero loading device 2 can be connected directly or via a connecting pipe (not shown) through the self-sealing pipe joints 18 and 19.

Similar to the hydraulic circuit 12 of the excavation rig 3, the tip of a return oil passage 21 led out from the control valve block 11 is connected to a downstream passage portion of the control valve block 11.

As a result, the return oil from the excavation-side control valve block 11 is returned to the lower part of the excavation-side hydraulic circuit 12 from the return oil path 21, and is transferred to the hydraulic tank 22 through the self-sealing pipe joint 19 and the excavation-side hydraulic circuit 10. be returned.

In the figure, 23 and 24 are the lift cylinders of the loading device 2, and the chill cylinders 25, 26, 27, 28, and 29 are! These cylinders are for the swing, boom, am, packet, and outrigger of the cutting device 3, and each of these cylinders 2129 is driven and controlled by each control valve 23a-29a.

Note that Figure 3 is a side view of the steering lever 30 of the machine 1, and Figure 4 is a side view of the steering lever 30 of the machine 1.
The figure shows a sectional view taken along line A-A in FIG. 3, which shows the steering lever 30.
and the steering clutch rod 31 are pivotally connected by a pivot pin 32, and the pivot pin 32 and the pin pivot hole 3 of the steering lever 30 are connected to each other by a pivot pin 32.
A heat-treated, highly hard pusher 34 is interposed between the pusher 3 and the pusher 3.

Since the present invention is constructed and operates as described above, when the loading device 2 is used for traveling operation, the pump 8 consumes only a part of the output of the engine 5, and the remainder is consumed for the traveling of the machine 1. 5 is not overloaded and can perform its traveling work well, but when the drilling rig 3 is used for stationary work, the pump 8 utilizes the entire output of the engine 5 at or close to the full power to move the drilling rig. 3, the stationary work capacity can be greatly increased.

Moreover, the configuration for this purpose only requires that the set pressure of the hydraulic circuit 12 of the excavation rig 2 be higher than the set pressure of the hydraulic circuit 10 of the loading device 3, which is less complicated and less expensive than the conventional structure. It can be easily implemented.

Furthermore, in the present invention, the tip of the return oil passage 21 from the control valve block 11 for fixed-field work is connected to the hydraulic circuit 1 for driving the drilling equipment.
Since it is connected to the terminal end of 2, the return oil path 2
Compared to the case where the tip of the oil return oil passage 21 is led out directly to the hydraulic tank 22 of the machine 1, the total length of the return oil passage 21 can be significantly shortened, and there is no need to interpose a pipe joint in the middle of the return oil passage 21. , the return oil passage 21 can be easily and inexpensively manufactured.

Moreover, only two pipe joints 18 and 19 are required for connecting and disconnecting the hydraulic circuit 12 for stationary work between the oil feed path 20 of the hydraulic pump 8 and the loading device drive pressure circuit 10, and the stationary work can be carried out easily. When the hydraulic circuit 12 for use is disconnected and the oil feed path 20 of the hydraulic pump 8 and the oil path 10 for traveling work are connected via both pipe joints 18 and 19, both pipe joints 18 and 19 are left open. The oil passage 2 is connected from the pipe fittings 18 and 19 without
No external water or dust can enter into the 0.10.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a side view of a tractor excavator and backhoe, Fig. 2 is a hydraulic circuit diagram, and Fig. 3 is a hydraulic circuit diagram.
The figure is a side view of the travel lever, and FIG. 4 is a sectional view taken along line AA in FIG. 1... This machine, 2... Traveling type working device, 3... Stationary type working device, 5... Engine, 7... Traveling device, 8
... Hydraulic pump, 10... Hydraulic circuit for driving 2, 1
1...12 control valve blocks, 12...3 hydraulic circuits for driving, 18, 19... pipe joints, 20... oil supply path, 21... return oil path.

Claims (1)

[Claims] 1. In a traveling/stationary type construction machine in which the excavator 3 is removably attached to the rear of the machine 1 which is equipped with the loading device 2 at the front, the engine 5 installed in the machine 1 is used to operate the machine 1. The traveling device 7 and the hydraulic pump 8 are configured to be able to be driven once, and a self-sealing pipe joint 18 is provided at each inlet side portion of the driving hydraulic circuit 12 of the excavation device 3 and the driving hydraulic circuit 10 of the loading device 2. 19, and the tips of the return oil passages 21 of each of the control valves 25a to 29a are communicated with the downstream passage portion of the control valve block 11 of the hydraulic circuit 12 for driving the drilling rig 1. The flow path on the downstream side of the control valve block 11 is configured to be able to be connected to the inlet side of the hydraulic circuit 10 for driving the loading device via a self-sealing pipe joint 19, and the hydraulic pump 8
The oil supply passage 20 is configured to be selectively connectable to the inlet side of the hydraulic circuit 12 for driving the excavating rig and the inlet side of the hydraulic circuit 10 for driving the loading device, and a relief interposed in the hydraulic circuit 12 for driving the excavating rig. A drive device for a traveling/stationary construction machine, characterized in that the set pressure of a valve 17 is set higher than the set pressure of a relief valve 16 interposed in a hydraulic circuit 10 for driving a loading device.