JPS5912287Y2 - Work equipment correction device for construction machinery - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a work machine correction device that enables scooping of earth and sand by horizontal extrusion of packets by operating only the arm portion of a construction machine that performs excavation and loading using packets.

Conventionally, when using construction machinery that excavates and loads using packets, when scooping earth and sand from the front of the vehicle into the packet, the packet is first moved forward by an arm cylinder installed between the boom and the arm, and the packet cylinder is shortened, and It is necessary to operate so that the packet is maintained horizontally.

Therefore, it is necessary to operate two or more operation valves at the same time, which makes the work complicated and also reduces work efficiency because the driver gets fatigued early.

This invention was made with the aim of improving this problem, and by providing a working machine correction device for construction machinery that allows packets to be pushed out horizontally by just operating the arm, it is possible to improve the scooping of earth and sand. It was designed to be easy to do.

This invention will be described in detail below with reference to an illustrated embodiment.

In the figure, reference numeral 1 denotes the body of a construction machine, such as a swinging excavator, which is rotatably mounted on an underbody 2 having crawler tracks 2a.

A boom 4 whose base end is pivotally supported to the vehicle body by a pin 3 is provided at the front of the vehicle body 1, and a boom cylinder 5 is provided at the tip end of the boom 4 so that the boom 4 can be raised and lowered in the vertical direction. The base end of the arm 6 is attached to the pin 7 at the tip of the arm 4.
It is pivoted by.

The tip of the arm 6 is rotatable in the front and back direction by an arm cylinder 8 suspended horizontally between the arm 6 and the boom 4, and a packet 9 is pivotally attached to the lower end of the arm 6 by a pin 10. has been done.

Further, a lever 11 is rotatably attached to the tip side of the arm 6, and the lever 11 and the bottom of the packet 9 are connected to each other by a link 12.
One end of a packet cylinder 13 is pivotally connected to the joint between the lever 1 and the link 12, and one end of a correction cylinder 14 is pivotally connected to the tip of the lever 11.

The other end of the packet cylinder 13 is pivotally attached to the tip of the boom 4, and the other end of the correction cylinder 14 is attached to the lower surface of the boom 4 on the vehicle body 1 side via a bracket 15 so as to be parallel to the arm 6. It is pivoted.

Each of the cylinders 5, 8, 13, and 14 is provided with hydraulic piping as shown in FIG.

That is, hydraulic pressure discharged from a hydraulic pump 16 driven by an engine (not shown) mounted on the vehicle body 1 is transmitted to the boom cylinder 5 via a boom operating valve 18 via a pipe line 17, and to a packet via a packet operating valve 19. cylinder 1
3 and further to the arm cylinder 8 via the arm switching valve 20.

Each of the operating valves 18 and 19 is connected to a boom operating pilot valve 22, a packet operating pilot valve 21, and an arm operating pilot valve 23, respectively, and is operated by pilot pressure supplied from these pilot valves 21 to 23. At the same time, part of the pilot pressure supplied to the packet operation valve 19 is supplied to the selection valve 25 via the check valve 24.

The selection valve 25 is located between the correction cylinder 14 provided in parallel with the boom cylinder 5 and the boom cylinder 5,
When the packet 9 is not operated, it is in position A due to the action of the return spring 26, and the compensation cylinder 14 is connected in parallel with the boom cylinder 5, and when the packet 9 is operated, it is switched to position B, and the boom cylinder 5 and compensation cylinder 14 are connected in parallel. At the same time, correction cylinder 1
It is designed to drain the hydraulic pressure inside 4.

The operation of storing earth and sand located in front of the vehicle body 1 into the packet 9 will now be described.

First, when the arm cylinder 8 is extended from the position shown in FIG. It flows from the pipe 27 through the selection valve 25 to the rod side of the boom cylinder 5, and the boom cylinder 5 is shortened.

Oil on the head side of the boom cylinder 5 flows into the head side of the correction cylinder 14 via the pipe line 28.

Therefore, the boom 4 is sequentially lowered as the tip of the arm 6 moves forward, so that the tip of the arm 6 is moved forward parallel to the road surface.

This also applies when the arm cylinder 8 is shortened.

In addition, the boom cylinder 5 and the correction cylinder 14 are set in advance so that the piston diameter, piston rod diameter, pressure receiving area ratio, etc. are equal in order to prevent a vacuum state from occurring due to a difference in the amount of oil flowing between them. ing.

On the other hand, as the tip of the arm 6 moves forward, the packet 9 maintains the cutting edge 9a horizontally as shown in FIG. The packet 9 is pushed forward, and the dirt in front is accommodated in the packet 9.

From this state, earth and sand can be scooped up into the packet 9 by switching the packet operation valve and rotating the packet 9 in the direction of arrow a.

At the same time, the selection valve 25 is switched to position B by part of the pilot pressure supplied to the packet operation valve 19 by the operation of the packet 9, so that all the oil in the correction cylinder 14 is drained and the operation of the packet cylinder 13 is controlled. does not cause any trouble.

Note that the above operation is the same in horizontal extrusion with the packet 9 held at a certain height.

Therefore, it is convenient to discharge the earth and sand in the packet 9 onto the loading platform of a transport vehicle.

It also has the effect of increasing the extrusion force during horizontal extrusion of the packet 9.

That is, during the excavation operation by pushing out and pulling out the packet 9, an excavation reaction force F as shown in FIG. 4 is generated at the tip i9a of the packet 9.

When the correction cylinder 14 of this invention is installed, the digging reaction force is F1, the force generated in the arm cylinder 13 is P, and the force generated in the correction cylinder 14 communicating with the boom cylinder 5 is Q. Then, the balance of the forces is FB − a Tomi P * β 0 Q, 7 −−−−−−−
-- ” (1) Here, α: Distance from the base point of arm 6 to excavation reaction force F1 β: Vertical distance from the base point of arm 6 to generated force P of arm cylinder 8, γ: From the base point of arm 6 Vertical distance to the generated force Q of the correction cylinder 14 According to the above formula (1), the excavation force F1 is calculated by If the excavation reaction force is F2, the force balance is F,.α=p.β
Song・1・・Song 1・・1・・−・・ (3) Then, the formula (
3), β F,=P. One, one, one, one...
・・・1・・・・・・(ri α and the difference is F1 Ft=Q−”・・・・・・・・・・・・・−・・
- (5) α Therefore, by providing the correction cylinder 14, the excavation reaction force can be increased by Q·1, and the excavation capacity can be improved by about 30% with the link ratio of the above embodiment compared to the conventional one.

This means that the arm cylinder 8 can be made smaller and lighter than the conventional one with the same capacity.

On the other hand, the acting force Q of the correction cylinder 14 may be positive or negative in some cases.

This is because when the excavation reaction force F acts from an upward direction (θ direction) from the line connecting the tip of the packet 9 and the pivot points of the boom 4 and the vehicle body, the boom cylinder 5 tends to be shortened, and the pressure on the head side is reduced. If the excavation reaction force F' flows into the correction cylinder 14 via the path 28 and acts in the direction of extending the correction cylinder 14, that is, in the positive direction, and conversely, the excavation reaction force F' acts from below (θ' direction), In contrast to the above, the correction cylinder 14 works in the shortening direction, that is, in the negative direction.

However, in actual work, the digging reaction force acts mostly in the positive direction, which improves digging capacity, but if it acts in the negative direction, the digging reaction force decreases by Q.L. However, since the vehicle body 1 with α is receiving an upward force at this time, the ground contact force of the crawler belt 2a is decreasing, and as a result, the effect of preventing slipping can be obtained.

Note that the same effect can be obtained even if one end of the correction cylinder 14 and one end of the packet cylinder 13 are pivotally connected to the lever 11.

As explained in detail above, this device has a correction cylinder installed in parallel with the arm, and this correction cylinder is connected in parallel to the boom cylinder via a selection valve that operates when the packet is operated. can be pushed out horizontally, making it easy to scoop up dirt, etc. from the front of the vehicle.

This makes the operation easier than the conventional method in which scooping is done by operating two or more operating valves, reducing operator fatigue and improving work efficiency.

In addition, by providing a correction cylinder, the potential energy of the vehicle weight can be added to the excavation force, increasing the excavation capacity. The size and weight of the device can be reduced.

Furthermore, since the correction cylinder is located on the outside of the arm and is installed almost parallel to the arm, the existing arm can be used as is, and the closed cross-section structure of the arm provides higher rigidity. It is economical as there is no need to make it large.

In addition, since the oil in the compensation cylinder is drained by the selection valve when the packet cylinder is operated, the tip of the boom does not fall during loading, which increases the rate at which the packets ascend, making loading work more efficient. Not only does it work well, but it also improves work efficiency by making it possible to excavate curved surfaces while operating the arm and packet.

[Brief explanation of drawings]

The drawings show one embodiment of this invention, in which Figure 1 is a side view of the arm cylinder when it is shortened, Figure 2 is a side view when it is extended, and Figure 3 is a side view of the arm cylinder when it is extended.
The figure is a hydraulic circuit diagram, and FIG. 4 is an explanatory diagram of the action of excavation reaction force. 1 is the vehicle body, 2 is the suspension, 4 is the boom, 5 is the boom cylinder, 6 is the arm, 8 is the arm cylinder, 9 is the packet, 11 is the lever, 13 is the packet cylinder, 14 is the correction cylinder, and 25 is the selection valve.

Claims (1)

[Scope of utility model registration request] A boom 4 that can be raised and lowered by a boom cylinder 5 is provided at the front part of a vehicle body 1 that can move freely by a foot shift 2, and an arm 6 that can freely rotate in the front and rear directions by an arm cylinder 8 is provided at the tip of the boom 4. At the same time, a rotatable packet 9 is mounted on the packet cylinder 13 at the tip of the arm 6.
A correction cylinder 14 is provided between the boom 4 and the lever 11 and link 12 that connect the packet cylinder 13 and the packet 9, and is located inside the arm 6 and is substantially parallel to the arm 6. The boom cylinder 5 and correction cylinder 14 of the packet cylinder 13 are connected in parallel between the correction cylinder 14 and the boom cylinder 5, and the oil in the correction cylinder 14 is drained when the packet cylinder 13 is operated. A work machine correction device for construction machinery, which is provided with a selection valve 25 for draining.