JPS5819827B2 - Hide Souchi Fusetuno - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a full-swing type backhoe equipped with an earth removal plate on the truck frame side that can be moved up and down.

In this type of backhoe, the attitude of the earth removal plate (height in percentage)
Depending on the up-and-down posture of the excavating rig and the rotating posture of the swivel table, a part of the excavating rig (mainly the boom cylinder) and the earth removal plate may come into contact with each other. It was necessary to always be aware of the positional relationship between the soil removal plate and the earth removal plate to avoid interference, which caused a great deal of mental fatigue during the work.

The present invention aims to solve the above problem and enable work to be carried out safely and easily at all times by automatically stopping the operation of the device when interference is about to occur.

Embodiments of the present invention will be described below based on the drawings.

Fig. 1 shows an overall side view of a fully rotating backhoe equipped with an earth removal device, in which a swivel platform 3 is hydraulically driven and mounted on a truck frame 2 equipped with a hydraulically driven crawler traveling device 1 so as to be able to fully rotate. A hydraulically driven excavation device 4 is connected to the front part of the swivel table 3, and the truck frame 2
An earth loading device is attached to which the earth removal plate 6 can be raised and lowered by a hydraulic cylinder 5.

Even when the excavation device 4 is most collapsed at a position corresponding to the left and right center of the earth removal plate 6 at the upper limit and reaches the lower limit position, the boom cylinder 7 at the downward lower limit position contacts the upper side of the earth removal plate 6. However, as shown in Fig. 2, there is a difference between the distance ρ1 from the left and right center of the earth removal plate 6 to the turning center P and the distance ρ1 from the end of the earth removal plate 6 to the turning center P. In addition, since the boom cylinder 7 is tilted downward, the boom cylinder 7 comes into contact with the upper side of the earth removal plate 6 when the swivel base 3 turns left and right from the above-mentioned state by an angle α or more.

That is, the two angle β portions on the left and right sides shown in FIG. 2 are the range in which the earth removal plate 6 at the upper limit position and the boom cylinder 7 at the lower limit position interfere.

In the above configuration, the present invention takes the following measures to enable interference to be detected in advance.

In other words, in FIG. 3, between the truck frame 2 and the swivel base 3, the hydraulic control circuit on the swivel base 3 and the traveling hydraulic motor circuit on the truck frame 2 side are connected by piping so as to be rotatable around the swivel center 2. As is well known, this center joint 8 has an outer case 8a connected to the truck frame 2 side, and a center pin 8b connected to the swivel base 3 side. Therefore, in the present invention, a flange-shaped insulating plate 9 is attached to the outer periphery of the center pin 8b, and two contacts a and b made of a conductive material are attached to the lower surface thereof concentrically with respect to the pivot center P. One brush C that can be slid along a-b is attached to the outer case 8a via an insulating material 10.

And both contacts a and b are each connected to one limit switch S.
2, the brush C is connected to another limit switch S1, and one limit switch S2
The other terminal of is connected to the solenoid part 11 of the electromagnetic switching valve v1 as shown in FIG. and this power supply is connected to ground via the center pin 8b.

The electromagnetic switching valve v1 connects in parallel to the pump P a control valve v2 of a hydraulic motor M for driving the swing base 3, a control valve V3 of the boom cylinder 1, and a control valve v4 of the hydraulic cylinder 5 for lifting the earth removal plate 6. It is arranged to open and close the oil passage d on the upstream side of the oil passage d, and is normally in an open state, and is configured to be in a closed state when the solenoid section 11 is energized.

The one limit switch S1 is placed in a proper position so as to be closed when the earth removal plate 6 reaches the upper limit, and the other limit switch S2 is placed in a suitable place so as to be closed when the boom cylinder 7 reaches the lower limit. has been done.

Further, as shown in FIG. 4, the two contact points a and b are arranged to correspond to an angular range that is larger by a certain angular range γ in the left-right direction than the interference-equivalent angular range β explained in FIG. 2,
Brush C and contact point a or b (!
: Turning angle detection mechanism S3 that detects the contact closing operation of
is configured.

That is, the limit switch S1 detects the upper limit of the earth removal plate 6.
, a limit switch S2 that detects the lower limit of the boom cylinder 7, and the swing angle detection mechanism S3 are connected to the electromagnetic switching valve v.
It is connected in series to the solenoid 11 and power supply 12 of No. 1.

In addition, 13 in FIG. 3 is a swing race provided on the truck frame 2, 14 is a swing drive pinion provided on the swivel base 3, and 84 in FIG. 5 is an automatic stop release switch, which is normally closed. It is being

The invention is constructed as described above, and the swivel base 3 is driven to swivel with the earth removal plate 6 at the upper limit and the boom cylinder 7 at the lower limit, and the boom cylinder 1 is moved within the detection swivel angle range θ. When the position corresponding to is reached, the circuit shown in Fig. 5 is closed and the electromagnetic switching valve
2 is in the swing operation state, the oil passage d is cut off and the hydraulic motor M is stopped, and interference between the earth removal plate 6 and the boom cylinder 7 is avoided.

In addition, when the automatic stop state is reached, the control valve v2 is first returned to neutral, and then the automatic stop release switch S4 is opened to return the switching valve v1 to the open state. direction, lower the earth removal plate 6, or raise the boom cylinder 7.

Also, if the earth removal plate 6 is raised by the hydraulic cylinder 5 while the boom cylinder 7 located at the lower limit is within the detection rotation angle range, the limit switch S1 is closed just before the earth removal plate 6 reaches the upper limit. Hydraulic cylinder 5 stops.

In addition, when the earth removal plate 6 is at the upper limit and the boom cylinder 7
Similarly, if the boom cylinder 7 is lowered within the detected rotation angle range θ, the contraction operation of the boom cylinder 7 will be automatically stopped until interference occurs.

In the embodiment, when the interference range approaches, the hydraulic circuit is rendered inoperable and all devices are stopped, but if a relay or the like is used, it is also easy to automatically stop only the devices that are operating as they approach.

As described above in the embodiments, the present invention detects the relative position of the earth removal plate 6 and the boom cylinder 7 (!:) using the earth removal plate upper limit position detection mechanism S1, the boom cylinder lower limit detection mechanism S2, and the rotation angle detection mechanism S3. When all of these detection results indicate that interference is approaching, the interference approach operation is automatically stopped, so the operator can concentrate on his work while the equipment he is operating can operate. , it is only necessary to return to a safe state by switching the operation in the interference approach direction to neutral or reverse only when the operation becomes impossible, so there is no need for special emergency operations even when interference approaches, and interference avoidance is extremely possible. It is safe and easy to do.

Therefore, the operator does not need to take special precautions to prevent interference, and can easily and efficiently perform excavation or earth removal work.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an embodiment of the present invention, in which Fig. 1 is an overall side view of a fully rotating backhoe equipped with an earth removal device, Fig. 2 is a schematic plan view of the main parts, and Fig. 3 4 is an enlarged vertical sectional view of the center joint section, FIG. 4 is a schematic plan view of the turning angle detection mechanism section, and FIG.
The figure is a circuit configuration diagram. 2... Truck frame, 3... Swivel base, 4... Excavation equipment, 6... Earth removal plate,
1...Boom cylinder, β...Angle range equivalent to interference, γ...Constant angle range, Sl...
... Upper limit position detection mechanism, S2 ... Lower limit position detection mechanism, s3 ... Turning angle detection mechanism.

Claims (1)

[Claims] 1 The truck frame 2 is equipped with an earth removal plate 6 that can be raised and lowered, and the revolving base 3 is equipped with the excavation device 4, so that the earth removal plate 6 is located at the upper limit and the boom cylinder 1 of the excavation device 4 is directed diagonally downward. In a full-swivel type backhoe, in which the boom cylinder 1 at the lower limit position and the earth removal plate 6 at the upper limit position interfere with each other in a constant rotation phase angle range β due to the rotation of the swivel base 3, the earth removal plate 6 is located at the lower limit position. Upper limit position detection mechanism S1 of 6 and lower limit position detection mechanism S of boom cylinder 7
2, and a turning angle detection mechanism S for detecting that the turning table 3 has reached a predetermined angle range before and after the interference equivalent angle range β.
3 are provided respectively, and all these detection mechanisms S1. S2. A fully rotating backhoe equipped with an earth removal device, characterized in that the interference approach operation is automatically stopped in conjunction with S3 being in a detection state.