JPS6044457B2 - Loader hydraulic translation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive device for hydraulic equipment such as a lift cylinder (dump cylinder) in a port for loading earth, sand, hay, etc. Remove the packet at the tip of the handle or a scooping tool such as a fork.
The purpose is to move the cargo in parallel to prevent it from falling.

The present invention will be explained as follows based on the drawings.

In Fig. 1, 1 is a vehicle chassis, 2 is a post erected thereon, and 3 is a lift arm whose root part is pivoted to the post 2 with a pin 4 so that it can rise freely, and a scooping body 5 is attached to the tip part with a pin 6 that allows it to move up and down. Rotatably attach to.

Reference numeral 7 denotes a single-acting lift cylinder whose bottom bracket is pivotally connected to the post 2 by a pen 8, and the tip of a ram 9 is fixed to the bracket of the lift arm 3 by a pin 10.

11 is a guide cylinder that connects the bottom bracket to pin 1.
2, the piston rod 13 is fixed to the lift arm 3 by a pin 14, and is provided on the same side as the lift cylinder 7.

Reference numeral 15 designates a double-acting dump cylinder installed along the tip of the lift arm 3, whose bottom bracket is pivoted to the bracket on the lift arm 3 with a pin 16 so as to be freely raised.
The piston rod 17 is connected to the scooping tool 5 by a pin 18.

The cylinders 7, 11, and 15 mentioned above are the left and right posts 2 on the chassis 1, the lift arm 3, and the scooping tool 5 at its tip.
Identical ones are provided on both sides of the In Figure 2, 19 is a dump operation valve for pump boat A.
, B, Cl tank boat D1, valve boat E, and cylinder boats F, G are used as three-position switching valves.

Reference numeral 20 denotes a lift operation valve, which is a three-position switching valve having a valve boat H1, a pump boat 11, a tank boat J1, a cylinder boat K1, a tank boat L1, and a cylinder boat N, M, and O.

Hydraulic pump 21 and boat A1 boat E (5H1 boat L
and the tank 22 are connected by circuits 23, 24, and 25, respectively, and a relief valve 26 is provided in the middle of the circuit 23. The rod side of the dump cylinder 15, the bottom side of the boat F1, and the boat G are connected by circuits 27 and 28. Lift cylinder 7 and boat N guide cylinder 11 and boat 0
and are connected by circuits 29 and 30. Branch circuit 27'' of circuit 27 to boat K, branch circuit 28'' of circuit 28 to boat M, branch circuit 23'', 23'', 23'' of circuit 23
"" to boats B, O, I, circuit 25, branch circuit 25
″, 25″ are connected to boats J and D, respectively. In addition,
Circuits 27, 2 are connected to the left and right pair of cylinders 7, 11, 15.
8, 29, and 30 are branched and connected in the same manner. In the neutral state Z of each valve 19, 20 shown in FIG. ，
M, O, and K are closed.

In this state, when the spool of the dump operation valve 19 is switched to the right side in the figure, boats B, F, G, and D are connected to each other, and the pressure oil from the pump passes through circuits 23'' and 27.
It flows to the rod side of the dump cylinder 15 and the piston rod 17 retracts, and the pressure oil on the bottom side is connected to the circuits 28 and 25''.
It returns to tank 22 through. Conversely, if the spool of the same valve 19 is switched to the left side in the figure, boats B, G, F,
O are connected to each other, and pressure oil from the tank is connected to circuits 23'' and 2.
8 to the phototom side of the basket cylinder 15, the piston rod 17 is extended, and the pressure oil on the rod side is connected to the circuit 2.
Return to pump boat C from 7. That is, the pressure oil from the pump flows to the bottom side where the piston in the cylinder 15 has a larger pressure receiving area, and the pressure oil on the rod side returning to the boat C flows to the bottom j side to increase speed. When the dump operation valve 19 is operated independently in this way and the piston rod 17 of the dump cylinder 15 is extended, the scooping tool 5 rotates counterclockwise about the pin 6. Further, when the piston rod 17 of the cylinder 15 is retracted, the scooping tool 5 rotates clockwise. Therefore, the scooping tool 5 can be operated independently at the scooping angle and the discharging angle. Next, when the spool of the lift operation valve 20 is switched to the right side in the figure with the valve 19 in the neutral position, the boats I, N, H, M, K, O
are applicable to each.

The pressure oil from the hydraulic pump 21 is supplied to circuits 23″″″, 2
9 to the lift cylinder 7, the ram 9 extends and the lift arm 3 stands up. At the same time, the pressure oil from the pump flows through the circuits 24 and 28'' to the bottom side of the dump cylinder 15, and the piston rod 17 is extended to extend the scooping tool 5.
rotates counterclockwise. At the same time, the pressure oil on the rod side of the dump cylinder 15 flows to the guide cylinder 11 through the circuits 27, 27'', 30. That is, in response to the lift arm 7 rising, the piston rod 13 of the guide cylinder 11
is pulled toward the extension side, and in response, the dump cylinder 15
The pressure oil on the rod side is supplied to the guide cylinder 11, and each cylinder 7, 11, 15 extends without any trouble. As described above, in response to the raising of the lift arm 3, the scooping tool 5 rotates counterclockwise, and the inclination caused by the raising is offset. That is, the scooping tool 5 rises while maintaining parallelism. Finally, when the spool of the lift operation valve 20 is switched to the left side in the figure with the valve 19 in the neutral position, the boats H, L, N
. The pressure oil returns to the tank.At the same time, the piston rod of the guide cylinder 11 is retracted, and the pressure oil is returned to the recirculating oil 30, 27'', 27
The oil flows to the rod side of the dump cylinder 15 and the piston rod 17 retracts, and the pressure oil on the bottom side flows into the circuit 28.
, 2", 25" and returns to the tank 22. That is,
The lift arm 3 is inverted, the scooping tool 5 rotates clockwise in response to this, the inclination is offset, and the scooping tool 5 descends while maintaining its parallel position. As explained above, the present invention includes a lift arm that is pivotably mounted to a post provided on a vehicle chassis so that its root can be raised, and a scooping body that is pivotably mounted to the tip of the lift arm so that an ascending scoop and a descending dump can be pivoted. is provided between the lift arm and the post, and the extension operation is performed hydraulically to raise the lift arm, and the contraction action is performed by the own weight of the lift arm and the scooping body, as well as the weight of the loaded object, and the lift arm is raised. A single-acting lift cylinder is provided between the scooping body and the lift arm, and its extension operation causes the scooping body to perform a downward dumping operation, and its contraction operation causes the scooping body to perform an upward scooping operation, a double-acting dump cylinder that hydraulically performs both operations of the scooping body; a single-acting guide cylinder that is installed between the lift arm and the post and expands when the lift arm ascends and contracts when it descends; It has three switching positions: rake, neutral, and dump. In the neutral position, the boat connected to both chambers of the dump cylinder is locked, and in the rake position, pressure oil from the hydraulic pump is supplied to the rod side chamber, and the bottom side chamber is connected to the tank. A dump operation valve has a boat that communicates with the tank, supplies pressurized oil from the hydraulic pump to the bottom side chamber in the dump position, and has a boat that communicates the rod side chamber with the tank, and has three switching positions: up, neutral, and down. In the raised position, pressure oil from the hydraulic pump is supplied to the bottom side chamber of the single-acting lift cylinder and the bottom side chamber of the dump cylinder, and the rod side chamber of the dump cylinder and the bottom side chamber of the guide cylinder are connected to the bottom side chamber of the dump cylinder. In the lowered position, the bottom side chamber of the lift cylinder and the bottom side chamber of the dump cylinder are communicated with the tank, and the rod side chamber of the gump cylinder and the bottom side chamber of the guide cylinder are connected to each other through a branch pipe. The lift cylinder is provided with a boat that communicates with the dump cylinder through a branch pipe in the rod side chamber, and a lift operation valve that locks the guide cylinder, the lift cylinder, and the connection boat containing the dump cylinder in the neutral position. When the arm is raised, return oil from the rod side chamber of the dump cylinder is introduced into the guide cylinder to make the amount of rotation of the scooping body in the downward dumping direction proportional to the amount of rise of the lift arm, and when the lift arm is lowered, the guide cylinder is discharged. Since oil is introduced into the rod side chamber of the dump cylinder and the scooping body is rotated in the upward scoop direction in proportion to the amount of descent of the lift arm, the lift arm can be operated by a single-acting lift cylinder. With this type of rotor, without making any major changes to the conventional rotor, by adding a guide cylinder, making slight improvements to the lift operation valve, and branching piping that includes a dump cylinder, the rotor can be scooped in proportion to the amount of elevation of the lift arm. The handle can be moved in parallel while correcting its posture to maintain a constant angle with respect to the ground, and the structure is simple and can be implemented at low cost.

That is, when the lift arm is raised, pressure oil is supplied from the hydraulic pump to the bottom side chamber of the lift cylinder and the bottom side chamber of the dump cylinder via the lift operation valve, and as a result, the lift arm rises, and the amount of rise is reduced. The guide cylinder is extended to enlarge the bottom chamber, and the rod side chamber of the dump cylinder is communicated with this bottom chamber via the lift operation valve. It is rotated in the dumping direction. Furthermore, when the lift arm is lowered, both the bottom side chambers of the lift cylinder and the dump cylinder are communicated with the tank via the lift operation valve, thereby allowing the lift arm to move the scooping body (including the load) and The lift arm descends due to its own weight moment, and at this time, the same external force acts on the bottom side chamber of the guide cylinder, sending pressurized discharged oil to the rod side chamber of the dump cylinder.
At this time, the resistance force of the dump cylinder in the rake direction is
Since the external force acting on the guide cylinder is superior to the self-weight moment of the scooping body (including the load), the dump cylinder moves through the guide cylinder in proportion to the amount of descent of the lift arm, and It can be rotated in the direction.

[Brief explanation of the drawing]

FIG. 1 is a side view of the main parts of the rotor, and FIG. 2 is a hydraulic circuit diagram. 1...Car chassis, 2...Post, 3...
...Lift arm, 7...Lift cylinder,
5...Scooping tool, 15...Dump cylinder,
11...Guide cylinder, 20...Lift operation valve, 19...Dump operation valve.

Claims (1)

[Claims] 1. A lift arm whose root part is pivotably mounted to a post provided on the vehicle chassis, a scooping body which is pivotably mounted to the tip of the lift arm so that a lifting scoop and a descending dump can be rotated, and a combination of the lift arm and the post. A single-acting type lift that is installed in between, and whose extension operation is performed by hydraulic pressure to raise the lift arm, and whose contraction action is performed by the weight of the lift arm and the scooping body, as well as the weight of the loaded object, to lower the lift arm. The cylinder is provided between the scooping body and the lift arm, and its extension action causes the scooping body to perform a downward dump operation, and its contraction action causes the scooping body to perform an upward scooping operation, and both operations of the scooping body are performed. A double-acting dump cylinder operated by hydraulic pressure, a single-acting guide cylinder installed between the lift arm and the post, which extends when the lift arm rises and contracts when it descends, and a scoop, neutral, and
The dump has three switching positions; the neutral position locks the ports connected to both chambers of the dump cylinder, and the scoop position supplies hydraulic pressure from the hydraulic pump to the rod side chamber, and the port connects the bottom side chamber to the tank. In the dump position, it supplies pressure oil from the hydraulic pump to the bottom side chamber, and has a dump operation valve with a port that connects the rod side to the tank, and has three switching positions: up, neutral, and down; In this case, pressure oil from the hydraulic pump is supplied to the bottom side chamber of the single-acting lift cylinder and the bottom side chamber of the dump cylinder, and the rod side chamber of the dump cylinder and the bottom side chamber of the guide cylinder are connected to a branch of the rod side chamber of the dump cylinder. In the lowered position, the bottom side chamber of the lift cylinder and the bottom side chamber of the dump cylinder are connected to the tank, and the rod side chamber of the dump cylinder and the bottom side chamber of the guide cylinder are connected to each other through piping. Equipped with a port that communicates with the rod side chamber through branch piping, and in the neutral position, the guide cylinder,
Equipped with a lift operation valve that locks connection ports to the lift cylinder and dump cylinder,
When the lift arm ascends, return oil from the rod side of the dump cylinder is introduced into the guide cylinder to make the amount of rotation of the scooping body in the downward dumping direction proportional to the amount of rise of the lift arm. A hydraulic parallel displacement device for a loader, characterized in that discharged oil is introduced into a rod side chamber of a dump cylinder, and a scooping body is rotated in a rising scoop direction in proportion to the amount of descent of a lift arm.