JPH01145401A - Flow control valve - Google Patents

Abstract

PURPOSE: To miniaturize an entire body of a device by providing regulator spools changing an orifice opening in accordance with a pressure produced by reversely developing a load pressure and a feedback pressure within a vertical compartment. CONSTITUTION: An upper edge of a regulator segment 24 is sealed with a plug 38. A regulator spool 46 pushed by an eccentric spring 54 and having a metering land 50 and an upper land 52 is provided within a sealed space. A load pressure is developed to a spring chamber of the regulator spool 46 and a feedback pressure is developed at the bottom surface 16 of the regulator spool 46. This allows to disuse a special sleeve or a differential area for regulating a flow to a switch road, so it is possible to minimize an entire body of a device.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates generally to fluid valves used to control fluid flow, and more particularly to fluid valves used to control fluid flow through a spool opening in a proportional directional valve. related to valves.

BACKGROUND OF THE INVENTION Valves and devices used to control fluid flow have been developed in the past. For example, US Pat. No. 4,361,169 discloses a multi-chamber control valve bank. The metering and logic elements of this valve bank consist of a control valve chamber connected to a signal chamber so that the fluid flow through the inlet of the valve is varied by the signals generated therefrom. The invention then utilizes a spool and hole requiring multiple lands and U-shaped passages to generate appropriate signals and control fluid properties.

Another U.S. Pat. No. 4,352,375 also discloses a control valve bank. The control valve bank of this patent is the fourth U.S. patent.
Similar to No. 361169, multiple lands are used along the intricate heart-shaped flow passages to control fluid flow around the dual feed passages.

Yet another U.S. Pat. No. 4,519,419 discloses a fluid valve that uses a hollow piston with multiple independent lands of different diameters and various seal diameters.

Additionally, U.S. Pat. No. 4,574,839 discloses a pressure compensated directional control valve. The valve provides a constant flow rate for a given fluid load regardless of the applied load and uses a sleeve valve insert and a piston mounted in a number of springs that generates a variable orifice. It moves to control fluid flow relative to the load.

An adjustable sleeve operates in conjunction with the hollow piston to provide the appropriate actuation to the valve.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved individual segment flow regulator that is simpler and less expensive to operate than conventional devices.

It is another object of the present invention to provide a compact individual segment flow regulator that does not require the use of special sleeves or differential areas to properly regulate the flow to the switching load. shall be.

Another object of the invention is to adjust the flow to the load;
It is an object of the present invention to provide an individual segment style flow regulator that uses a single spring in association with a single spool.

How these and further objects of the invention are achieved will be explained in connection with the description of preferred embodiments of the invention in conjunction with the drawings. However, in general, the purpose is to provide a spool with two lands and a separate segment with a hole with two lands, which have the same diameter, plug, spring and sensing passage from the main spool of the valve. This is accomplished in a formal flow regulator. The supply oil flowing between the two lands of the hole is separated from the sensing pressure by the land of the - spool which is slidable within the hole. The other spool lands are usually unsupported and meter the oil supply. The metering land of the regulator spool opens away from the land of the valve hole to allow supply fluid to flow and to shut off the supply. When the main spool of the device opens, a spring chamber above the spool senses load pressure. The pressure in the spring chamber opens the metering spool, thereby increasing the flow and increasing the pressure drop across the opening in the main spool area. A feedback pressure is developed at the bottom of the metering land of the spool to oppose the preload force of the spring chamber biasing spring and the pressure of the load. This feedback force reduces the flow and pressure drop across the main spool.
As the preload force of the biasing spring is increased beyond that, the regulator spool closes. Therefore, the feedback land at the bottom of the spool is also a metering land for controlling the supply pressure to the regulated pressure.

The regulator can also act as a limiter to limit maximum segment pressure by including an orifice in the communication line between the main spool load sensing flow passage and the regulator valve load sensing spring chamber.

- Once the pressure drop caused by the pilot relief valve exceeds the spring preload force acting on the regulator spool, the regulator spool cuts off the flow to the main spool and
By generating a small amount of leakage, the set pressure of the pilot relief is maintained.

Other variations and modifications of the invention will become apparent to those skilled in the art upon reading this specification, and may fall within the scope of the opening claims following the preferred embodiments described below. For example, it is included within the scope of the present invention. - (Example) The regulator of the present invention has a housing 20 in FIG.
is embodied within. Two holes are drilled into the housing 20, the first of which is the main spool hole 22, and these two holes lead to the regulator compartment 24. Cylinder ports 26,27 communicate with main spool hole 22. The main spool hole 22 intersects the regulator section 24 at right angles, and the regulator section 24 reaches the main spool hole 22 at its lower end.

A generally U-shaped chamber 28 is connected to the sides of the main spool 30 on either side of the regulator compartment 24. The main spool 30 has a pair of land portions 32, and these land portions 3
2 allows fluid communication between chamber 28 and compartment 24;
or limit it. Furthermore, the main spool 30 has a land portion 34.
These lands 34 allow or restrict fluid communication between the chamber 28 and the cylinder ports 26,27. Movement of the main spool 30 in the left-right direction selectively allows communication between the cylinder ports 26,27 and the regulator compartment 24. When the main spool 30 shifts, cylinder ports that do not receive fluid from a source communicate with the appropriate exhaust boat 36 or 37.

Regulator compartment 24 is sealed at its upper end with a plug 24 that uses an O-ring 40 to ensure a tight seal. Section 24 has a first metering land 42 and an upper sliding spool land 44 that forms a support for a spool 46 . Fluid from supply port 48 is routed between lands 42 and 44 to regulator compartment 2.
4. As shown in FIG. 3, the regulator spool 46 also includes two lands, namely a metering land 50.
and an upper land 52 that slides within the upper hole land 44 . In the preferred embodiment, regulator spool lands 50.52, hole lands 42.44 are
All have an apparent upward radius. Bias spring 54 biases regulator spool 46 downward toward main spool hole 22. This downward displacement is caused by the spool 46
It is restricted by the upper restriction ring 53. Spring chamber 56 is defined by the top of regulator spool 46 and the walls of plug 24 and regulator compartment 24. U-shaped chamber 28 is in fluid communication with spring chamber 56 via sensing passageway 58 .

The lower surface 60 of regulator spool 46 functions as a feedback surface. That is, the pressurized fluid in the regulator compartment 24 below the land 42 has a feed pack signal on the lower surface 60 of the regulator spool 46, which counteracts the force created by the bias spring 54.

FIG. 1 shows the valve of the present invention in a neutral position, ie, in a position where no fluid flows to either cylinder port 26 or 27. FIG. As seen in FIG. 1, the handle 31, which controls the position of the main spool 30, is moved up and down in an arc. When the handle 31 moves, the main spool 30 moves.

FIG. 2 shows the main spool moved onto the fabric as a result of the handle 31 being raised. This rightward movement of the main spool 30 establishes open fluid communication between the cylinder port 26 and the relief 36, thereby causing the cylinder port 26 to
6 to the exhaust port 36. Similarly, fluid communication is also established between cylinder port 27 and supply hole 48 .

The feed stream from boat 48 is fed to regulator spool 46
The unsupported land 50 of the valve hole is spaced apart from the land 42 of the valve hole so that it is constricted by that land 50. When the metering land 50 of the regulator spool 46 is supported, the land is closed.

The load pressure from the boat 27 is applied to the main direction control spool 30.
When the switch is switched to the right as shown in FIG. 2, it is threaded into the spring chamber 56 above the regulator spool 46. When the main spool 30 opens the metering area along the land 34, a load pressure is sensed within the spring chamber 56. The load pressure acting on the top of the regulator spool 46 opens the metering land 50 of the regulator spool from the bore land 42. When land 50 of the regulator spool opens,
The increased flow into main spool 30 increases pressure across the main spool area that opens at land 32. When the pressure drop across main spool 30 equals the spring force from spring 54 acting on the end of the regulator spool at surface 60, then spool 46 adjusts around its steady state position. This state of equilibrium is created in part by the preloading force of the biasing spring plus the loading pressure acting within the spring chamber on the top surface of the regulator spool 46. These combined forces cause metering land 50 of the regulator spool to open. Both of these forces are equally opposed by regulated pressure acting on the underside 60 of spool 46.

This opposing force is a feedback force used to close the metering land 5θ of the regulator spool when the flow and pressure drop across the main spool 30 exceeds the preload force of the bias spring 54. The regulated/feedback pressure is upstream of the main spool section that is open at land 32 and is at a higher pressure than the load pressure due to the pressure drop across main spool 30. Therefore, the pressure drop across the main spool 30 is equal to the spring preload force acting on the regulator spool 46 since the sum of the load pressure and the spring preload force is generally equal to the regulated pressure. The metering land 50 of the regulator spool is in a position where the forces are balanced, and the metering land 50 of the regulator spool is in a position where the force is balanced.
The main spool metering area along the main spool changes and/or automatically adjusts its position within the chamber 24 as the load pressure or supply fluid pressure to the regulator spool 46 changes.

A feedback surface 60 at the end of the spool 46 provides a metering land 50 that throttles the supply pressure from the boat 48 to a specified pressure.
is part of. The supply fluid pressure is throttled down to a lower prescribed pressure and the flow passes around the metering land 50 of the spool 46 and directly impinges on the region 60 at the end of the flow spool 46 . The pressure adjusted to the specified pressure is applied to the spool 4 when the fluid flows to the main spool area opened at the land 32.
A feedback force is generated directly at the end 60 of 6.

Angle 51 is added to the spool metering land 50 of the regulator to compensate for fluid forces acting on spool 46. Regarding the angle 51 of the spool 46, the spool movement increases progressively as the fluid force descends closer to the spool opening between the metering land 50 and the valve orifice land 42. Movement of the spool increases the effectiveness of the spring preload.

This offsets the opposing fluid forces.

Another feature that can be added to the device is its ability as a regulator to act as a maximum segment pressure limiter. An orifice 62, shown in phantom in FIG. 2, is located in the transmission line 58 between the main spool load sensitive flow path 28 and the load sensitive spring chamber 56 of the regulator valve. Thus, a pressure drop occurs across the orifice 62 when the pilot relief valve is connected to the spring chamber 56 and the relief valve opens at a preset value. - once the pressure drop exceeds the spring preload of the spring 54 on the spool 46 of the regulator, the spool 46 of the regulator
The flow to the main spool 30 is cut off, and sufficient leakage is caused between the lands 50 and 42 to maintain the pressure set at the pilot relief. This limits the maximum operating pressure to maintain a fixed clamping force on the cylinder or a fixed torque on the rotary motor.

Various variations, modifications and other applications will be apparent to those skilled in the art. Accordingly, the preferred embodiments described above are to be construed as illustrative rather than limiting.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the regulating valve of the present invention in its neutral position, FIG. 2 is a sectional view showing the regulating valve supplying regulating fluid to the operating port, and FIG. 3 is a line taken along the line of FIG. 1. 3-3 is a side cross-sectional view of the valve; FIG. 20: Housing, 22: Main spool hole 24:
Compartment, 30: Main spool 46: Adjustment spool, 56: Spring chamber. (4 others) Procedural amendment December 27, 1988

Claims (1)

[Claims] 1. A flow regulating valve comprising: a valve body having a supply port; an actuating port connected to a fluid pressure device that produces a load pressure on the actuating port; fluid being able to be discharged from the actuating port. an evacuation port; movable to allow a first orifice to open to a preselectable area between the actuation port and the evacuation port, and the actuation port communicates with the evacuation port; a main spool that is also movable to a position in which the adjustment spool is biased downwardly by a biasing force in the vertical compartment, the adjustment spool having an upper land and a lower land; comprising: a flowing horizontal hole, wherein the upper hole land of the vertical compartment and the upper land of the adjustment spool define an upper chamber of the vertical compartment and a lower chamber of the vertical compartment; a vertical compartment intersecting the feed port, the vertical compartment having an upper hole land and a lower hole land respectively positioned on opposite sides of the feed port; a main spool disposed within the horizontal hole; , forming a body seal and support between the actuation port and the vertical compartment; the lower land of the adjustment spool and the lower land of the vertical compartment being of variable size; forming a second orifice; the size of the second orifice being determined by the position of the adjustment spool within the vertical compartment; and sensing a load pressure within the upper chamber. a sensing passageway communicating the upper chamber with the actuation port is further provided to communicate the upper chamber with the actuation port; the main spool is positioned such that the first orifice opens into a preselected area; and a load. Pressure is sensed in the upper chamber and is operable to force a top surface of the adjustment spool downwardly; feedback pressure in the lower chamber is operable to force a bottom surface of the adjustment spool upwardly. the position of the adjusting spool is determined by the difference between the feedback pressure acting on the bottom of the adjusting spool and the combined pressure of the load pressure and the biasing force acting on the top of the adjusting spool; A flow regulating valve featuring: