JPH0433449Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention relates to a composite flow diverter valve that has a built-in relief valve and operates a pilot hydraulic valve with a solenoid valve, and is suitable when installed on a shovel type truck equipped with a breaker. The present invention relates to a composite flow diverter valve.

(Prior Art) When a hydraulic breaker is installed in place of a bucket on a shovel-type truck, such as a power shovel, the piping to the breaker is normally connected to the power shovel's service valve. The circuit breaker is driven using the power source. The control valve group in a power shovel is generally as shown in Fig. 5, and the rotation of the power shovel's body, the vertical movement of the arm and boom, etc. are controlled by individual control valves 101 to 103 via hydraulic motors and hydraulic cylinders. do. Therefore, when stopping the work machine of a power excavator and driving the breaker, the hydraulic pump 10
The entire amount of high-pressure hydraulic oil from pump 104 flows into the breaker, but if the arm, boom, etc. are moved up and down at the same time as the breaker is driven, the high-pressure hydraulic oil from pump 104 is sent toward those working machines, and the remaining of hydraulic fluid flows into the breaker.

(Problem that the invention aims to solve) When using a shovel truck equipped with a breaker, the machine body tends to move and the arm and boom move up and down even when the breaker is being driven. In many cases, this cannot be avoided if it is done quickly. In the shovel type truck, as described above, the high pressure hydraulic oil from the hydraulic pump 104 is consumed due to the movement of the machine body and the vertical movement of the arm and boom, and the amount of hydraulic oil flowing into the breaker service valve 100 is reduced. As a result, if the machine body is moved and the arm or boom is moved up and down at the same time as the breaker is driven, the driving force of the breaker will drop sharply, reducing the efficiency of the crushing operation. Furthermore, since the pump characteristics (hydraulic pressure-oil amount characteristics) of power shovels differ depending on the manufacturer, a problem arises in that the driving force of the breaker is influenced by the pump performance.

(Means for solving the problem) As a result of various studies regarding the above-mentioned problem, the present inventor proposed a new composite diverting valve in which the pilot hydraulic valve is operated by a solenoid valve, and when this valve is used, We have discovered that it is possible to preferentially drive the breaker in a shovel type truck.

As shown in FIG. 1, the composite flow dividing valve 2 according to this invention is a pilot hydraulic valve 1 provided with a P port 4 for input and A ports 6 and H ports 8 for output.
0 and a solenoid valve 12 that is essentially 4 ports and 2 positions.
and a relief valve 16 connected to the port 14 of the solenoid valve. In this case, the solenoid valve 12 does not have to be configured with a complete four ports as shown in FIG. It is also possible to connect to three ports.

The hydraulic valve 10 has pilot passages 20 and 2 connected to the oil chambers 46 or 47 on both end faces of the spool 18.
2, respectively, and has a spool position 24 (FIG. 2) which divides the P port 4 to the output ports 6, 8, and a position 26 (FIG. 2) which communicates substantially only with the A port 6. The solenoid valve 12 has a solenoid 28 above it, and at one spool position 29 (FIG. 2), the flow path 56 branching from the H port 8 of the hydraulic valve 10 is closed, and the oil chamber 47 of the hydraulic valve 10 is connected to the tank. It communicates with port 30. Also, at the other position 32 (FIG. 2), the tank port 30
The flow path 56 branching from the H port 8 of the hydraulic valve 10 communicates with the oil chamber 47 of the hydraulic valve and the relief valve 16.

The composite flow diverter valve 2 of this invention can be applied to various uses, but a typical example is when it is installed on a shovel type truck, and the truck has at least a boom and is equipped with a breaker. . For example, as shown in Figure 3, a shovel type truck is
Such as a power shovel or a boxhoe. The composite flow dividing valve 2 is installed near the operator's cab 36, separately from the valve groups 100 to 103 of the power shovel 34, as shown in FIG. For example, the composite flow dividing valve 2 is installed in front of the valve groups 100 to 103,
The pipeline from the hydraulic pump 104 is directly connected to the P port 4 of the diverter valve 2, the A port 6 is connected to the input pipeline 38 of the valve groups 100 to 103, and the H port 8 is connected to the input pipeline of the breaker 40. 42.

(Function) At the valve position shown in Fig. 2, the breaker 4
0, the breaker 40 can be preferentially driven by energizing the solenoid 28 and switching the hydraulic valve 10 to the right position 24. As a result, the driving force of the breaker 40 does not decrease even if the machine body is moved and the arm or boom is moved up and down at the same time when the breaker 40 is driven. If the breaker 40 is not to be driven, the hydraulic valve 10 may be switched to the left position 26 via the solenoid valve 12, and the body may be moved and the arm or boom may be moved up and down in the same manner as usual.

(Example) To explain this invention based on the drawings, FIG. 1 shows a composite flow dividing valve 2 according to the invention, and a pilot hydraulic valve 10 is located on the right side of FIG. The spool 18 is slidably housed in the housing 44 of the diverter valve 2, and the P port 4, the A
Port 6 and H port 8 are provided. In the housing 44, oil chambers 46 and 47 are formed on the left and right end surfaces of the spool 18, respectively, and a compression spring 48 (indicated by a chain double-dashed line) is arranged in the left oil chamber 47, and the spring always moves the spool 18 to the right side. It is energizing. The spool 18 is provided with pilot passages 20 and 22, both of which communicate the H port 8 with an oil chamber 46 or 47 through appropriate restrictions. On the other hand, the solenoid valve 12
is located on the upper left side of FIG.
A spool 50 is housed therein so as to be vertically slidable. An oil chamber 51 below the spool 50 communicates with the tank port 30, and a compression spring 52 is installed in the oil chamber.
(shown by the two-dot chain line), the spring always urges the spool 50 upward. The port 14 of the solenoid valve 12 branches into two directions, with one passage 53
communicates with the left oil chamber 47 of the hydraulic valve 10 through a suitable restriction, and the other passage 54 connects with the relief valve 16. A port 55 is located near the upper part of the port 14, and this port is connected to the H port 8 through an appropriate restriction.
It communicates with a branch passage 56 of. The illustrated position of the spool 50 is a de-energized state of the solenoid 28;
In this state, the port 14 communicates with the tank port 30 via the spool annular groove 59 and the center hole 57. energizes solenoid 28 and spool 5
Pushing 0 downward connects the ports 55 and 14 via the spool annular groove 58 and closes the tank port 30 with the spool peripheral wall. The built-in relief valve 16 is located at the lower left side in FIG. 1, and has a compression spring 60 (indicated by a two-dot chain line) disposed within the housing 44, which presses the hard ball 61 against the valve seat 62. The center hole 63 of the sheet 62 is
It opens and closes with a hard ball 61 and communicates with the passage 54. Passage 64 provided in the housing peripheral wall of the relief valve 16
is connected to the tank port 30. This relief valve 16 is a direct acting type.

The composite diverter valve 2 is installed near the operator's cab 36 of the power shovel 34, and as shown in FIG. group 100
What is necessary is just to connect the input pipe line 38 of ~103 and the H port 8 with the input pipe line 42 of the breaker 40. In addition, in order to control the energization to the solenoid 28,
Install switch 65. power shovel 34
As shown in Fig. 3, the rear end of a boom 66 bent at the center is pivotally attached to the fuselage, and an arm 67 is pivotally attached to the tip of the boom 66, and these rotations are controlled by a pair of boom cylinders. 68 and other hydraulic cylinders. A hydraulic breaker 40 (for example, trade name Okada Ion UB14) is pivoted to an arm 67 and a bucket ring 70 via a bracket 69. Chisel 71 is breaker 40
A piston (not shown) of the breaker 40 protrudes from the lower end surface of the breaker 40 and causes hydraulic oil to flow into the pipe line 42.
make a reciprocating motion. Hit the rear end of the chisel.

When not driving the breaker 40, switch 65
To keep the solenoid 28 open, the solenoid 28 is not energized, and the spool 50 of the solenoid valve 12 remains stationary in the position shown in FIG. 1, ie, position 29. At this time, the left oil chamber 47 of the hydraulic valve 10 is connected to the port 1 of the solenoid valve 12.
4. It communicates with the tank port 30 through the spool groove 59 and the center hole 57 to lower the pressure. In the illustrated state, since the H port 8 communicates with the P port 4, the same pressure was acting on the left and right oil chambers 46 and 47 of the hydraulic valve 10 via the pilot passage 20 or 22, but the left oil chamber A pressure difference is created by lowering the pressure at 47. Therefore, as long as the pressure in the H port 8 is maintained at a predetermined level or higher, the pressure in the right oil chamber 46 will overcome the elasticity of the compression spring 48 and move the spool 18 to the left position 26, and the H port 8 will move to the P port 4. Although it is shut off, a small amount of oil always flows into the H port 8, so the pressure in the right oil chamber 46 is maintained and the spool 18 is kept stationary at the left position 26. As a result,
Breaker 40 remains stopped and valve group 1
00 to 103, the aircraft can be moved and the arm and boom can be moved up and down in the same way as before.

Next, when the switch 65 is closed and the solenoid 28 is energized, the spool 50 of the electromagnetic valve 12 is pushed downward, connecting the branch passage 56 to the passage 53 via the spool groove 58, and closing the tank port 30. Since the left and right end surfaces of the spool 18 of the hydraulic valve 10 usually have the same area, when the pressure in the left oil chamber 47 increases due to the closure of the tank port 30 and the pressure difference described above becomes smaller, the spool 18 moves to the right. Start. Further, via passages 56 and 53,
By forming a flow path connecting the port 8 to the left oil chamber 47, the pressures in the oil chambers 46 and 47 become equal, so the elasticity of the compression spring 48 causes the spool 18 to
It moves to the position shown in the figure and stops at the right position 24.
In the illustrated shape of the spool 18, the A port 6 seems to be blocked, but a predetermined amount of oil always flows from the P port 4 to the A port 6, and the hydraulic oil in the P port 4 is transferred to the A port. 6 and H port 8. As a result, the breaker 40 is preferentially driven, and the hydraulic oil flowing into the input conduit 38 via the A port 6 allows the aircraft to be moved.

When the breaker 40 is driven, if the pressure in the H port 8 increases due to a change in the load of the hydraulic oil due to hardening of the material to be crushed, etc., the passage 56 and the spool groove 5
8 and 54 to act on the relief valve 16,
Move the hard ball 61 to the left. As a result, hydraulic valve 1
The left oil chamber 47 of No. 0 communicates with the tank port 30 via the passages 53, 54, the relief valve 16, and the passage 64, and the pressure decreases. While limiting the amount, excess oil is allowed to flow out from the A port. Due to this function, the pressure on the A port side does not fluctuate with respect to pressure fluctuations on the breaker 40, that is, the H port side, and the hydraulic oil discharged from the hydraulic pump 104 can be used effectively.

FIG. 4 shows another example of the use of the diverter valve 2 of the present invention, in which the A port 6 of the diverter valve is connected to the input conduit 38, and the H port 8 is connected to the input conduit 42 via a check valve 72. do. In the power shovel 34, pipes 78 and 80 are connected to the head side oil chamber 74 and rod side oil chamber 76 of the boom cylinder 68, respectively.
and both pipes are connected to, for example, a control valve 103. The pressure switch 82 detects the hydraulic pressure in the pipe line 80 of the rod-side oil chamber 76, and connects the solenoid 28 of the solenoid valve 12 to a DC circuit 84 in which the switch is installed. Furthermore, if there is a service valve 100 that is not in use, it is preferable to connect the A port of the valve to the input pipe line 42 of the breaker 40 and shut off the B port. At this time, even if the power to the DC circuit 84 is turned off,
When the valve 100 is switched to the left position, the breaker 40 can be started in the conventional manner, and the hydraulic fluid in the pipe 42 will not flow back toward the hydraulic valve 10 by the check valve 72.

Next, move the breaker 40 downward, and the chisel 7
When the tip of the boom 66 comes into contact with the ground 86, the boom 66 stops, but hydraulic oil still tries to flow into the rod-side oil chambers of the cylinders 68, 68, so the pressure inside the oil chambers rises rapidly. As a result, pressure switch 82 is actuated and solenoid 28
energized, the solenoid valve 12 switches to position 32 and automatically starts the breaker 40. At this time, if the service valve 103 is switched to the left position, all the excess oil not used by other working machines will also flow into the breaker 40, so the breaker can be driven more strongly.

(Effects of the invention) When the composite flow diverter valve according to this invention is installed on a shovel-type truck equipped with a breaker, priority is given to driving the breaker, which prevents the movement of the machine and the vertical movement of the arm and boom during crushing work. The driving force of the breaker does not decrease even if the Therefore, it is possible to move the machine body and move the arm and boom up and down simultaneously with the crushing operation, thereby effectively increasing the efficiency of the crushing operation. By using this composite flow divider valve, the amount of hydraulic oil flowing into the breaker can always be controlled to an appropriate amount, so even if the breaker is driven preferentially, the reduction in the driving force of other working machines is relatively small. In addition, in this composite flow divider valve, the switching is controlled by a solenoid, and the solenoid is energized by opening and closing a switch or automatically, reducing the possibility of erroneous operation by the operator.
This will reduce the occurrence of accidents.

[Brief explanation of the drawing]

Figure 1 is a schematic vertical cross-sectional view of a composite diverter valve according to this invention, Figure 2 is a circuit diagram showing a hydraulic circuit in which the composite diverter valve of this invention is installed, and Figure 3 is a diagram showing the installation of the hydraulic circuit shown in Figure 2. A side view of the power shovel, FIG. 4 is a circuit diagram showing another example of the use of the composite diverting valve of this invention, and FIG. 5 is a circuit diagram showing a conventional hydraulic circuit. 2...Composite flow divider valve, 4...P port, 6...A
Port, 8... H port, 10... Pilot hydraulic valve, 12... Solenoid valve, 14... Port, 16...
...Relief valve, 18...Spool, 20, 22...
...Pilot passage, 28...Solenoid, 34...
...Power shovel, 40...Breaker, 100~
103... Operation valve group.

Claims (1)

[Claims for Utility Model Registration] 1. A composite flow dividing valve in which a pilot hydraulic valve with a relatively large switching flow rate is operated by a solenoid valve, and a position where the input port is divided into both output ports and a position where the other output port is closed. A pilot hydraulic valve having a substantially four-port two-position solenoid valve and a relief valve connected to port 14 of the solenoid valve, in one position of the solenoid valve, the other of the output ports of the hydraulic valve The branch flow path is closed and the oil chamber 47 of the hydraulic valve is communicated with the tank port, and at this time, the hydraulic pressure in the oil chamber 46 overcomes the spring pressure in the oil chamber 47 to move to the left position 26, and the solenoid valve In the other position, the direct passage to the tank port is closed and the branch passage at the other output port of the hydraulic valve is connected to the oil chamber 47 and the relief valve of the hydraulic valve, in which case the oil in the oil chamber 47 is A composite flow dividing valve characterized in that the pressure and spring pressure overcome the hydraulic pressure in the oil chamber 46 to reach the right position 24. 2. The valve according to claim 1 of the utility model registration, in which the branch pipe line at the other output port of the hydraulic valve is connected to the port 14 of the electromagnetic valve through an appropriate restriction. 3. A small amount of hydraulic oil flows into the other output port of the hydraulic valve even when the spool is in the closed position, and this hydraulic oil flows into the oil chamber 46 of the hydraulic valve through the pilot passage 22 and increases the pressure in the oil chamber. The valve according to claim 1, which is registered as a utility model, allows the spool to stand still at the left position by overcoming the elasticity of a spring stored in the oil chamber 47 of the hydraulic valve.