JP4145008B2 - Multiple control valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multiple control valve optimum for use in, for example, a forklift.
[0002]
[Prior art]
The conventional multiple control valve shown in FIGS. 2 and 3 is used for a forklift control circuit. FIG. 2 shows this forklift control circuit.
In FIG. 2, a priority valve 2 is provided on the upstream side of the supply flow path 1. The priority valve 2 supplies a constant flow rate to the control flow circuit 3 side such as a power steering circuit among the flow rates supplied to the supply flow path 1, and supplies an excess flow rate higher than the constant flow rate to the valve units 4 and 5. Like to do.
[0003]
The upstream valve unit 4 controls the lift cylinder 6, and the downstream valve unit 5 controls the tilt cylinder 7.
Now, when the spools provided in the valve single bodies 4 and 5 are in the neutral position shown in the figure, the pressure fluid that has passed through the priority valve 2 passes through the neutral flow paths 9 and 10 of both the valve single bodies 4 and 5 and the tank port 8. Is returned to the tank. When the spools of the valve single bodies 4 and 5 are switched from the neutral position to either the left or right position, the neutral flow paths 9 and 10 are blocked. Therefore, at this time, the pressure fluid flowing into the supply flow channel 1 is guided to the parallel passage 11.
[0004]
The parallel passage 11 communicates with a branch passage 12 connected to the inflow port 4 a of the valve unit 4 and a branch passage 13 connected to the inflow port 5 a of the valve unit 5.
The branch passages 12 and 13 are provided with load check valves 14 and 15, respectively. The load check valves 14 and 15 permit only the flow from the branch passages 12 and 13 to the inflow ports 4a and 5a.
[0005]
Therefore, when the pressure fluid is guided to the parallel passage 11 as described above, the pressure fluid pushes open the load check valves 14 and 15 and flows into the inflow ports 4a and 5a, from there, the lift cylinder 6 or the tilt cylinder 7 To be supplied.
FIG. 3 specifically shows the single valves 4 and 5. As is clear from FIG. 3, the valve units 4 and 5 have the same specific configuration.
[0006]
That is, these valve single bodies 4 and 5 formed the connecting body a by forming parallel flow holes 11a and 11b in the valve bodies 16 and 17, respectively, and connecting the valve bodies 16 and 17 as shown in the figure. When these parallel flow holes 11a and 11b communicate with each other, a parallel passage 11 is formed.
In this way, the connecting body a having the parallel passage 11 is provided with the inlet member 18 outside the valve unit 4 located on the upstream side, and with the outlet member 19 outside the valve unit 5 located on the downstream side.
[0007]
The inlet member 18 is formed with an import IN communicating with a pump (not shown), and the outlet member 19 is formed with a tank port 8 communicating with a tank.
The parallel passage 11 communicates with the inflow ports 4a and 5a via the branch passages 12 and 13, and load check valves 14 and 15 are provided in the branch passages 12 and 13, respectively.
[0008]
As is apparent from FIG. 3, the load check valves 14 and 15 have one of the poppets 14 a and 15 a facing the spring chambers 20 and 21 and the other facing the seat portions 22 and 23.
The spring chambers 20 and 21 are provided with springs 33 and 34. Normally, the poppets 14a and 15a are pressed against the seat portions 22 and 23 by the spring force of the springs 33 and 34.
[0009]
The load check valves 14 and 15 configured as described above have the poppets 14a and 15a as a boundary, the seat portions 22 and 23 facing the inlet members 18 and 19, and the spring chambers 20 and 21 facing the outlet member 19 side. Yes.
When the spring chambers 20 and 21 are directed to the outlet member 19 side in this way, the spring chamber 21 of the valve unit 5 on the most downstream side opens to the side surface of the valve body 17. However, the opening of the spring chamber 21 is blocked by the outlet member 19. In other words, the outlet member 19 also has a function for closing the spring chamber 21.
[0010]
Now, when the spool is switched, the pressure fluid is guided to the parallel passage 11, but the pressure fluid pushes the load check valves 14 and 15 open and is guided to the inflow / inflow ports 4a and 5a.
[0011]
[Problems to be solved by the invention]
In the conventional multiple control valve as described above, the spring chamber 21 must be blocked by the outlet member 19. In other words, the conventional multiple control valve absolutely requires the outlet member 19 to close the spring chamber 21. Therefore, there is a problem that the number of parts increases by the amount of the outlet member 19.
An object of the present invention is to provide a multiple control valve in which an outlet member is not required and the number of parts can be reduced.
[0012]
[Means for Solving the Problems]
In this invention, when an inlet member is provided in one of the connecting members connected to a plurality of single valves, the pressure fluid is guided from the import provided in the inlet member, while the spools incorporated in the single valves are switched. The pressure fluid flowing from the import pushes the load check valve provided in the parallel passage and is guided to the supply port, and the load check valve is provided in this spring chamber with one of the poppets as a spring chamber. This is based on the premise of a multiple control valve in which the poppet is pressed against the seat portion by the spring force of the spring.
While assuming multiple-control valve described above, the present invention is load check valve provided in each valve alone, only toward the spring chamber to the inlet member, the seat and the inlet member in opposite directions Rutotomoni The spring chamber of the single valve adjacent to the inlet member is blocked by the inlet member, and the spring chamber of the other single valve is blocked by the valve body of the adjacent upstream valve .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
In the embodiment shown in FIG. 1, the load check valves R1 and R2 are provided in the branch passages 24 and 25 in the same manner as in the prior art. However, the load check valves R1 and R2 of this embodiment are reverse in direction to the conventional ones.
That is, the load check valves R1 and R2 provided in each of the valve single bodies 4 and 5 have their spring chambers 26 and 27 directed toward the inlet member 28 and the seat portions 29 and 30 directed in the opposite direction to the inlet member 28. .
[0014]
By determining the direction of the load check valves R1 and R2 as described above, the spring chamber 27 of the load check valve R2 in the most downstream valve unit 5 opens to the valve body 16 side of the upstream valve unit. . Therefore, the spring chamber 27 of the load check valve R2 is blocked by the valve body 16 of the upstream valve unit 4.
Further, the spring chamber 26 of the load check valve R1 in the upstream valve unit 4 opens to the inlet member 18 located on the upstream side, but this is also blocked by the inlet member 18.
[0015]
Therefore, in the case of this embodiment, the outlet member 19 is not required to block the opening of the spring chamber 27 of the load check valve R2. Thus, since the outlet member 19 is not required to block the spring chamber 27, in this embodiment, the parallel flow hole 11b is directly blocked by the valve body 17 of the valve unit 5 on the downstream side, and the conventional outlet is used. The tank port formed in the member 19 is formed in the inlet member 18. That is, both the pump port 31 and the tank port 32 are formed in the inlet member 18.
[0016]
Since both the pump port 31 and the tank port 32 are formed in the inlet member 18 as described above, the conventional outlet member 19 becomes unnecessary. That is, in this embodiment, since the outlet member 19 that has been conventionally required is unnecessary, the number of parts can be reduced accordingly.
The configuration other than the above is the same as the conventional one. Therefore, the same reference numerals are given to the same components as those in the conventional art.
[0017]
【The invention's effect】
According to the multiple control valve of the present invention, since the outlet member that has been conventionally required is unnecessary, the number of parts can be reduced accordingly. Since the number of parts is small, the cost for parts and the cost for assembling parts can be saved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a conventional circuit diagram for controlling a forklift.
FIG. 3 is a cross-sectional view of a conventional multiple control valve.
[Explanation of symbols]
4 Valve unit 5 Valve unit 11 Parallel passage 16 Valve body 17 Valve body a Connecting member 18 Inlet member R1 Load check valve R2 Load check valve 26 Spring chamber 27 Spring chamber 29 Seat portion 30 Seat portion

Claims (1)

An inlet member is provided on one of the connecting members that connect a plurality of valve units, and pressure fluid is introduced from the import provided on the inlet member. On the other hand, when the spool incorporated in each valve unit is switched, it flows from the import. The pressure fluid pushes and opens the load check valve provided in the parallel passage and is guided to the supply port. The load check valve has one of the poppets as a spring chamber, and the spring of the spring provided in the spring chamber. In a multiple control valve that is configured so that the poppet is pressed against the seat part by force, the load check valve provided on each valve unit has its spring chamber facing the inlet member and the seat part facing away from the inlet member. And the spring chamber of the single valve adjacent to the inlet member is closed with the inlet member. Single valve of the spring chamber, multiple-control valve to which the structure to close the adjacent upstream side of the valve alone in the valve body.

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