WO2016000987A1

WO2016000987A1 - Annular piston valve

Info

Publication number: WO2016000987A1
Application number: PCT/EP2015/063877
Authority: WO
Inventors: Khaled MALOUF
Original assignee: Erhard Gmbh & Co. Kg
Priority date: 2014-07-02
Filing date: 2015-06-19
Publication date: 2016-01-07
Also published as: DE102014212786A1

Abstract

The invention relates to an annular piston valve comprising the following features: - a housing that has an inlet and an outlet; - a rotationally symmetrical hollow member in the housing; - an annular duct between the housing and the hollow member; - a piston which is located in the hollow member and can move in and against the direction of flow; - two perforated cylinders which are concentric to the piston and are stacked inside one another; - one of the perforated cylinders has a greater axial length than the other perforated cylinder.

Description

Needle Valve

The invention relates to a plunger valve according to the preamble of

Claim 1.

Such spool valves include a housing having an inlet port and an outlet port. Inlet opening and outlet usually align with each other. The housing encloses a rotationally symmetrical hollow body. Housing and hollow body together form an annular gap through which a medium flows. On the Umströmungswege the flow of the medium is also annular. The hollow body encloses a piston. Housing and hollow body are coaxial with each other. The piston is displaceable in the hollow body in the direction of the flow of the medium and in the opposite direction by operation from the outside.

At the downstream end of the hollow body is a perforated cylinder through which the annular flow passes and passes to the subsequent outlet, to which a pipeline is connected. The perforated cylinder is also arranged coaxially to the piston and hollow body. It at least partially blocks the annular flow. It is also known, instead of a single hollow body to use two hollow body, which are nested in one another.

Such annular piston valves serve to reduce the pressure in the flow of the valve. This happens because energy is consumed when flowing through the holes in the perforated cylinder or in the perforated cylinders.

Numerous embodiments of such spool valves have become known. See DE 43 04 972 A1, DE 93 20 686 U1. DE 20 2012 003 033 U1 describes an annular piston valve, in which two nested one another

Punching cylinder of the same axial length to the downstream end of the piston are connected and are axially displaceable by this in the sense of shutting off and opening the annular gap.

In another, undocumented embodiment is a single

Perforated cylinder provided, which is stationary, but in which the annular gap can be opened and closed by a sleeve with a closed lateral surface. Sleeve and hole cylinder are coaxial with each other.

The invention has for its object to make a plunger valve such that the risk of cavitation when flowing through the

or the hole cylinder is reduced, and that the pressure reduction runs in a controlled manner. In addition, the annular piston valve should be flexible for various applications and be inexpensive. This object is achieved with a plunger valve according to claim 1.

Accordingly, two nested in a known manner

Hole cylinder used, but - unlike the prior art - have different axial lengths. In this case, preferably the outer

Punch cylinder the largest axial length, and the subsequent one is slightly shorter. Also, a third hole cylinder may be used, which in turn is within the second, and which is shorter than the second.

As a result, the following is achieved in detail: The cavitation risk is greatly reduced by the embodiment according to the invention, since the pressure reduction is distributed over two or more perforated cylinders. At the same time, however, the throughput of medium - that is, the amount of the medium per unit time - can be adjusted by exchanging a perforated cylinder unit with certain lengths of the individual perforated cylinder against another perforated cylinder unit with other lengths of the individual perforated cylinder. Of the

But throughput can be achieved without the effort of exchanging two Very easy to adjust perforated cylinder units, that the

Punch cylinder unit is made displaceable from the outside in the piston valve.

The prior art and the invention are explained in more detail with reference to the drawing. The following is shown in detail:

FIG. 1 shows a known annular piston valve according to the state of the art

Technology.

Figure 2 shows a schematic representation of an annular piston valve with a double annular piston in a first position.

FIG. 3 shows the article of FIG. 2 in a second position.

FIG. 4 shows the article of FIG. 2 in a third position.

The annular piston valve shown in FIG. 1 comprises a housing 1 with an inlet 1 .1 and an outlet 1 .2. In the housing there is a hollow body 2. Between the hollow body 2 and housing 1 remains an annular channel 3, which is flowed through during operation of the annular piston valve of a medium. In the hollow body 2 is a piston rod 4. This is by a mechanism in the direction of

Flow (see arrow) or displaced in the opposite direction, by means of a mechanism comprising a threaded spindle 5 and a

Helical toothing 6. On the piston rod 4, a piston 7 is fixed, which thus can also go back and forth, in the sense of a shut-off

or releasing the flow coming from the annular channel 3.

You can see a hole cylinder unit 8. This is permanently installed. In the

shown position of the piston 7 flows through the medium through the holes of the hole cylinder unit 8 and reaches the outlet 1 .2. If the piston 7 after shifted to the right, so the holes of the hole cylinder unit 8 are shut off, and there is no medium flows through the annular piston valve.

Figures 2 to 4 show an embodiment according to the invention. The figures show only the necessary components. The valve according to the invention has, just as in the prior art, a housing 1, and also an annular channel 3 arranged therein. The device also comprises a piston which is located inside the hollow body 2, but which is not shown here. The piston carries at its downstream end a perforated cylinder unit 8. This comprises a first perforated cylinder 8.1 and a second perforated cylinder 8.2.

These are one piece with each other. Punch cylinder 8.1 is longer in the axial direction, as a hole cylinder 8.2.

The perforated cylinder unit 8 is fixedly connected to said piston, not shown, so that upon displacement of the piston in the axial direction, the perforated cylinder unit performs a displacement.

At the downstream end of the housing 1 is a sealing ring 9. Figure 2 shows that position of the perforated cylinder unit 8, in which it is furthest away from the sealing ring 9.

In the illustration according to FIG. 3, the perforated cylinder unit 8 is extended somewhat further in the downstream direction. The free end of hole cylinder 8.1 is already on the sealing ring.

In Figure 3, the hole cylinder unit 8 is extended so far that hole cylinder 8.1 fits snugly against the inner wall of the sealing ring 9. Instead of the illustrated perforated cylinder unit with two individual perforated cylinders, it is quite conceivable, even a unit with a large number of individual

Punch cylinders project, for example four five or six. Here you will use a hole cylinder with a small wall thickness.

The embodiment of the perforated cylinder unit according to the invention has the following advantages: By the plurality of individual, nested one another

Punched cylinders reduce the flow forces per hole cylinder accordingly, and thus the risk of cavitation.

- With the embodiment of the invention can on the throughput

Be influenced. In the illustrated embodiment according to Figures 2 to 4, the entire hole cylinder unit 8 in

Flow direction or this move against. If the perforated cylinder unit 8 is in the position shown in FIG. 2, a relatively large flow quantity emerges from the annular channel 3. If the perforated cylinder unit 8 is in the embodiment shown in FIG. 3, only the holes of the two remain for the through-flow

Punch cylinder 8.1 and 8.2.

In the position shown in Figure 4, the flow remain only some of the holes of the perforated cylinder 8.1, and all holes of the cylinder hole 8.2.

The perforated cylinder unit according to the invention may be preceded by a filter, for example a fixed hole cylinder, as already known from the prior art. Instead of the described perforated cylinder unit 8, which is displaceable in the direction of flow or against this, it is conceivable to use a multipart

Provide perforated cylinder unit that is stationary.

LIST OF REFERENCE NUMBERS

casing

inlet

outlet

hollow body

annular channel

piston rod

screw

helical teeth

piston

Hole cylinder unit

perforated cylinder

poetry

Claims

claims

1 . Ring piston valve comprising the following features:

1 .1 a housing (1) having an inlet (1 .1) and an outlet (1.2);

1 .2 in the housing (1) arranged rotationally symmetrical hollow body (2);

1 .3 an annular housing provided between housing (1) and hollow body (2);

1 .4 one in the hollow body (2) arranged piston (7), in

Flow direction or against this is displaceable;

1 .5 two perforated cylinders (8.1, 8.2), which are arranged concentrically to the piston (7) and nested in one another;

characterized by the following features:

1 .6 one of the hole cylinder (8.1, 8.2) has a greater axial length, as the other hole cylinder (8.2).

Second annular piston valve according to claim 1, characterized in that the shorter hole cylinder (8.2) within the longer hole cylinder (8.1) is arranged.

3. annular piston valve according to claim 1 or 2, characterized in that more than two perforated cylinders are provided, whose axial length decreases from outside to inside.

4. plunger valve according to one of claims 1 to 3, characterized

in that the perforated cylinder unit 8 is firmly connected to the piston (7).

5. plunger valve according to one of claims 1 to 3, characterized

in that the perforated cylinder unit 8 is stationary.

6. annular piston valve according to one of claims 1 to 5, characterized

characterized in that a sleeve with a closed lateral surface is provided, which is arranged coaxially with the perforated cylinder unit 8, and which is movable in a closed position or in an open position.