JP2591753Y2 - Hydraulic pilot valve - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pilot valve for outputting hydraulic oil having a pressure proportional to the operating force of a lever.

[0002]

2. Description of the Related Art A spool for communicating and shutting off an inlet port and an outlet port is provided in a valve body, and this spool is biased and held at a shut-off position by a metering spring to form a pressure reducing valve.
A disk is provided on a lever that is swingably supported on the valve body, the push rod pushed by this disk is pushed up by a centering spring to hold the lever in a neutral position, and the lever is operated to push the push rod with the disk. 2. Description of the Related Art There is known a hydraulic pilot valve that presses a spool in a communication direction via a metering spring to reduce high-pressure oil at an inlet port in accordance with a lever operation stroke and output the oil from an outlet port.

[0003]

In such a hydraulic pilot valve, the lever is returned to the neutral position and held, and the centering spring and the metering spring are disposed coaxially with the spool of the pressure reducing valve. The pressure reducing valve part becomes large and assembly work becomes troublesome.Moreover, the number of centering springs required is the same as the number of pressure reducing valves. Get higher.

Therefore, an object of the present invention is to provide a hydraulic pilot valve capable of solving the above-mentioned problems.

[0005]

A lever 3 having a disk 4 is swingably supported on a valve body 1, and a ring-shaped groove 5 is formed in an annular groove 5 formed outside the lever support portion of the valve body 1. The spool 6 is inserted, and the spool 6 is pressed against the disc 4 with the centering spring 7 to release the lever 3.
In the neutral position, and the valve body 1 has an inlet port 10
A spool 12, which communicates and shuts off the air with the outlet port 11, a push rod 13 operated by the disk 4, and a feeling spring 14 interposed between the push rod 13 and the spool 12 to provide a pressure reducing valve. Pilot valve.

[0006]

[Operation] Since the centering spring 7 for holding the lever 3 in the neutral position is provided at a position different from the spool of the pressure reducing valve, the structure of the pressure reducing valve is simple and compact, and the assembling work of the pressure reducing valve is performed. And the center ring spring 7 pushes up the ring-shaped piston 6 along the annular groove 5 so that the lever 3 is set to the neutral position. 3 can be returned to the neutral position and held. Even when a plurality of pressure reducing valves are provided, it is sufficient to provide one center spring, so that the cost can be reduced.

[0007]

[Embodiment] As shown in FIG.
A lever 3 is swingably supported in an arbitrary direction via a universal joint 2 at a substantially central portion of the plane of FIG. 1, and an arc-shaped disk 4 is mounted on the lever 3. An annular groove 5 is formed on the outer periphery of the lever 3 support portion of the valve body 1, and a ring-shaped piston 6 is slidably fitted in the annular groove 5, and the piston 6 is fitted with a center ring spring 7. The lever 3 is held at the neutral position by pushing up on the annular projection 8 near the inner periphery of the disk 4. This annular projection 8
Instead, a plurality of balls may be radially supported near the inner periphery of the disk 4.

A plurality of spool holes 9 are formed at radial positions on the outside of the annular concave groove 5 of the valve body 1, and the spool hole 9 communicates with an inlet port 10 and an outlet port 11, and a spool 12 and a pusher. The rod 13 is inserted,
A metering spring 14 is provided between the spool 12 and the push rod 13, and an auxiliary spring 15 is provided on the opposite side of the metering spring 14 to hold the spool 12 in the shut-off position, and 4 against the projection 16 from the outer periphery,
By operating the lever 3 to push down the push rod 13 with the disk 4, the spool 12 is pushed via the metering spring 14 in the direction that connects the inlet port 10 and the outlet port 11, thereby forming a pressure reducing valve. The push rod 13 and the disk 4 may be connected via a rod.

Next, the operation will be described. When the lever 3 is in the neutral position, the state shown in FIG. 1 is established, the inlet port 10 and the outlet port 11 are shut off by the spool 12, and the discharge pressure oil of the hydraulic pump 17 stops.

When the lever 3 is operated in the direction of the arrow, the push rod 13 is pushed down by the disk 4, whereby the spool 12 is pushed down via the feeling spring 14 so that the inlet port 10 becomes the small diameter portion 18 and the shaft hole 19.
To the outlet port 11, and the discharge pressure oil of one hydraulic pump is reduced in pressure from the output port 11 and output. This output pressure becomes higher sequentially with respect to the lever stroke S as shown in FIG.

When the hand is released from the lever 3, the center ring spring 7 pushes the disk 4 through the piston 6 to return the lever 3 to the neutral position, the force of the feeling spring 14 becomes weak, and the spool 12 returns to the shut-off position. I do.

FIG. 3 shows a push rod 13 and a spool 12.
The upper portion of the spool hole 9 is a large-diameter hole 9a, a plug 20 is attached to the large-diameter hole 9a, a push rod 13 is fitted into the plug 20, and a spool is attached to the push rod 13. small径杆21 of 12 by a gap S ₁ are relatively displaced linked.

[0013] In this way, the output pressure when operating the only lever 3 meet the gap S ₁ between the small径杆21 and the push rod 13 becomes abruptly high as shown in FIG. 4, then the lever operation stroke Correspondingly, the pressure becomes higher sequentially.

[0014]

Since the centering spring 7 for holding the lever 3 at the neutral position is provided at a position different from the spool of the pressure reducing valve, the structure of the pressure reducing valve portion is simple and compact, and the assembly of the pressure reducing valve portion is achieved. The work becomes easy, and the lever 3 is set to the neutral position by pushing up the ring-shaped piston 6 along the annular groove 5 by the center spring 7. 3 can be returned to the neutral position and held. Even when a plurality of pressure reducing valves are provided, it is sufficient to provide one center spring, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a table showing a relationship between a lever stroke and an output pressure.

FIG. 3 is a cross-sectional view showing another example of a connecting portion between a spool and a push rod.

FIG. 4 is a table showing a relationship between a lever stroke and an output pressure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Valve body, 3 ... Lever, 4 ... Disk, 5 ... Annular groove, 6 ... Piston, 7 ... Centering spring, 9
... Spool, 10 ... Inlet port, 11 ... Outlet port, 1
3 ... Push rod, 14 ... Feeling spring.

Claims (2)

(57) [Scope of request for utility model registration] 1. A lever 3 provided with a disk 4 on a valve body 1.
A ring-shaped spool 6 is inserted into an annular groove 5 formed outside the lever support portion of the valve body 1, and the spool 6 is pressed against the disk 4 by a centering spring 7. The lever 3 is held at a neutral position, the valve body 1 has a spool 12 communicating and blocking an inlet port 10 and an outlet port 11, a push rod 13 operated by the disk 4, a push rod 13 and a spool 12 A hydraulic pilot valve provided with a feeling spring 14 interposed between the pressure pilot valve and the pressure reducing valve. 2. The push rod 13 and the spool 12.
Hydraulic pilot valve according to claim 1, wherein the opposed with a predetermined gap S ₁ a.