DE102022000635A1 - reverse current limiter - Google Patents

Abstract

The invention relates to a backflow limiter (10) with a channel element (12), with a first through-opening (14) which is fluidically connected to a second through-opening (16) through a channel (18), wherein in the channel (18) at least a flow guide device (20) for dividing a fluid flow of a fluid flowing through the channel (18) into a plurality of directed partial flows is arranged, wherein the backflow limiter (10) has an essentially rotationally symmetrical outer contour and the at least one flow guide device (20) consists of an im Substantially rotationally symmetrical impact ring (22) and an essentially rotationally symmetrical impact body (24) which is connected to the impact ring (22) by at least one radially arranged web (26) and is oriented to form partial flows.

Description

The invention relates to a backflow limiter with a channel element according to the preamble of patent claim 1.

A backflow limiter can be designed, for example, in the form of a Tesla valve. A Tesla valve is a device that can function as a passive, fluidic valve. In principle, a Tesla valve is a check valve with no moving mechanical parts. The essence of the classic Tesla valve is the blocking of a fluid flow in one direction, while the direction other than the flow direction is hardly impeded. The Tesla valve thus represents a backflow preventer which, however, is designed without moving parts that are therefore susceptible to wear.

A basic principle of the Tesla valve is to deflect a partial flow of a flowing fluid and thus a fluid flow in the blocking direction or in the blocked direction in such a way that it impedes the remaining fluid flow, thereby impeding the entire flow. For this purpose, in a Tesla valve, the partial flow is alternately deflected slightly in one direction in one plane and deflected back there in a loop-shaped channel onto the fluid or the fluid flow, or which has not penetrated the loop channel. In the further course, this distraction can sometimes take place in one direction and then in the other. In the direction of flow or through-flow, however, the fluid can flow relatively unhindered through the channel, which is only slightly winding in this direction. By lining up several of these deflections and loops, the blocking effect of the Tesla valve can be increased, but this also makes it correspondingly long or large.

the DE 10 2021 002 680 A1 shows a ventilation device for an interior of a motor vehicle with a duct, a Tesla valve being arranged in a central part of the duct.

The disadvantage of Tesla valves in general is that they cannot be used, for example, in narrow bores due to their shape. Thus, backflow limiters in the manner of a Tesla valve are generally particularly long and assume a particularly large volume, in particular in relation to a volumetric flow.

It is therefore the object of the present invention to provide a backflow limiter which can be used as a non-return valve without having moving parts, and at the same time the volume or the installation space of the backflow limiter is particularly small relative to the volume flow of a fluid in order to achieve particularly high efficiency .

This object is achieved according to the invention by the subject matter of the independent patent claim. Advantageous refinements and developments of the invention are specified in the dependent patent claims as well as in the description and in the drawing.

The backflow limiter according to the invention comprises a channel element which has a first through-opening which is connected to a second through-opening in a fluidically conductive manner by a channel, with at least one flow guide device in the channel for dividing a fluid stream of a fluid flowing or flowing through the channel into a plurality of directed partial streams is arranged. The partial flows are oriented or directed towards one another by the flow guide device in such a way that when the fluid flows through the channel from the first through-opening to the second through-opening, the partial flows are at least partially directed towards one another, as a result of which a flow resistance is higher than when the fluid flows through in Direction of passage through the channel from the second through-opening to the first through-opening, in which the partial flows are in the same direction and/or meet at a flat angle.

In order to be able to do without mechanically movable components in a particularly advantageous manner and to provide a particularly component-optimized backflow limiter, the backflow limiter has an essentially rotationally symmetrical outer contour and the at least one flow guide device consists of an essentially rotationally symmetrical impact ring and an essentially rotationally symmetrical, in particular inner one , Impact body, which is connected to the impact ring by at least one radially arranged web and is oriented to form the partial flows formed.

In other words, a backflow limiter is provided with a first inlet and outlet opening and a second inlet and outlet opening, which has a flow guide device which, in a first flow direction from the first to the second inlet and outlet opening, causes partial flows to be directed against one another and Flow is impeded while the partial flows formed in a second flow direction from the second inlet and outlet opening to the first inlet and outlet opening are rectified and/or in fla at a small angle so that the flow is less impeded.

The backflow limiter is characterized by the fact that it is designed as an insert with an essentially rotationally symmetrical contour and is composed of at least one essentially rotationally symmetrical impact ring and at least one associated rotationally symmetrical inner impact body, which are connected to one another by means of at least one radially aligned web. The impact ring in conjunction with the impact body forms the at least one flow guide device. The backflow limiter can be used particularly advantageously in round bores or flow channels due to its essentially rotationally symmetrical outer contour. Essentially rotationally symmetrical means that, for example, with an outer contour that is circular due to the rotational symmetry, slight deviations from a circle to an elliptical shape are possible. Additionally or alternatively, essentially rotationally symmetrical means that, for example, the at least one web connecting the impact ring and the impact body can break the rotational symmetry on the impact body or on the impact ring in a partial area.

The invention is based on the finding that the classic Tesla valve expands predominantly in one plane, while the height of the channel is significantly less than the width of a channel construction of the Tesla valve for reasons of flow resistance. This is not suitable for use in a round hole. Alternatively, venturi nozzles could be used, for example, but in order to achieve a significant change in the return flow, a large number of these venturi nozzles would have to be connected in series, as a result of which a corresponding valve would become very long.

Furthermore, hat-shaped disks with a nozzle-shaped constriction are known, which can be arranged in round bores and can also form a type of blocking device for a fluid flow, with the flow forming annular vortices on the disks. This can be supported by the middle passages through these discs becoming smaller and smaller in one direction, but this also means that a cross section is reduced for a fluid flow and the usable valve cross section is therefore small in relation to the total volume, which means that this is not suitable for optimizing the installation space.

With a conventional Tesla valve, the flow can always be directed in a different direction and there be guided to a dead end. However, this does not make sense in a substantially rotationally symmetrical arrangement.

A basic idea of the invention is that the fluid flow or the fluid stream and the individual partial flows generated by the at least one flow guide device repeatedly flow into the outer area and then back into the inner area of the in particular essentially rotationally symmetrical channel, which is designed as a bore, for example to steer. There, the partial flows should then be guided in such a way that they impede the remaining flow as much as possible. This is achieved by an alternating arrangement of the impact rings on the outside of the bore and impact bodies inside. The impact bodies are preferably held in their respective position by, in particular, three streamlined small webs.

By designing the rings and the impact body appropriately, the flow is purposefully directed counter to the rest of the flow. A good blocking effect is thus achieved with particular utilization of the installation space by just a few such pairs of impact bodies or by the at least one and in particular a plurality of flow guide devices. In order to achieve good flow in the flow direction, care should be taken to maintain a particularly uniform cross-sectional area in the channel of the channel element of the backflow limiter. For this purpose, corresponding cones can be provided on both sides of the impact body. “Both sides” is to be understood as meaning that one side is assigned to the first through-opening and the other side is assigned to the second through-opening.

One advantage of the backflow limiter according to the invention is that its volume is small in relation to the volume flow and/or its blocking ratio, which puts the volume flow in one direction (blocking direction) in relation to that in the other direction (opening direction), is large.

In an advantageous embodiment of the invention, the outer contour of the backflow limiter is cylindrical.

In a further advantageous embodiment of the invention, several flow guide devices are arranged one behind the other and thus in particular in a row in the channel element, these being oriented to one another in such a way that the flow resistance when the fluid flows through the channel from the first passage opening to the second passage opening is particularly high. In other words, the multiple flow lines The devices are oriented in such a way that their transmission directions point in the same direction.

In a further advantageous embodiment of the invention, the backflow limiter and/or the at least one flow guide device are designed in one piece or several flow guide devices arranged one behind the other, and in particular their impact rings and impact bodies, are supported on one another.

In a further advantageous embodiment of the invention, the impact ring is concave and/or conical in shape towards its annular opening counter to the passage direction on its side facing the second through-opening and/or it has an annular or circumferential groove on its side facing the first through-opening. Additionally or alternatively, the impact body is conically shaped in the passage direction and/or counter to the passage direction and/or has an annular or circumferential groove on a side facing the first passage opening.

Further advantages, features and details of the invention result from the following description of a preferred exemplary embodiment and from the drawing. The features and combinations of features mentioned above in the description and the features and combinations of features mentioned below in the description of the figures and/or shown alone in the figures can be used not only in the combination specified in each case, but also in other combinations or on their own, without going beyond the scope of the leave invention.

• 1 eine schematische Seitenansicht eines Rückstrombegrenzers;
• 2 eine schematische Schnittansicht entlang einer ersten Ebene des Rückstrombegrenzers gemäß 1;
• 3 eine schematische Draufsicht des Rückstrombegrenzers gemäß 1; und
• 4 eine schematische Schnittansicht entlang einer zweiten Ebene des Rückstrombegrenzers gemäß 1.

It shows:

• 1 a schematic side view of a backflow limiter;
• 2 a schematic sectional view along a first level of the backflow limiter according to FIG 1 ;
• 3 a schematic top view of the reverse current limiter according to FIG 1 ; and
• 4 a schematic sectional view along a second level of the backflow limiter according to FIG 1 .

1 shows a schematic side view of a backflow limiter 10 with a channel element 12, with a first through-opening 14 and a second through-opening 16, which are fluidly conductively connected to one another via a channel 18 of the channel element 12. At least one flow guide device 20 for dividing a fluid stream of a fluid flowing through the channel into a plurality of directed partial streams is arranged in the channel 18 . The partial flows are directed towards one another by the at least one flow guide device 20 in such a way that when the fluid flows through the channel 18 from the first through-opening 14 to the second through-opening 16, a flow resistance is higher than when the fluid flows through the through-flow direction through the channel 18 from from the second through-opening 16 to the first through-opening 14, in which the partial flows are directed in the same direction and/or meet at a flat angle.

In order to be able to form the backflow limiter 10 in a particularly advantageous manner so that it has a particularly high flow resistance in the blocking direction against the flow direction and at the same time can be made particularly compact, the backflow limiter 10 has an essentially rotationally symmetrical outer contour. Furthermore, the at least one flow guide 20, such as in the 2 , which shows a section along the AA plane, is formed from an essentially rotationally symmetrical impact ring 22 and from an essentially rotationally symmetrical impact body 24, which is connected to the impact ring 22 by at least one radially arranged web 26, the impact ring 22 and the Baffle 24 are oriented to form the partial flows to each other. Advantageously, the outer contour and thus the shape of the channel element 12 and thus in particular of the entire backflow limiter 10 is cylindrical.

The impact rings 22 and impact bodies 24 can be produced by simple processes such as turning and/or pressing and can be connected to the webs 26, which are designed in particular as spacer webs and/or sleeves, to form ring impact body pairs. This valve or the backflow limiter 10 designed in this way can, for example, be easily inserted into a bore and secured there, for example, by means of a press fit, caulking, screwing, gluing and/or in some other way.

As 3 shows, three webs 26 per flow guide device 20 can be oriented at an angle of 120° to one another, for example, and thereby connect the impact body 24 to the impact ring 22 .

4 shows another sectional view through the backflow limiter along the in 3 drawn BB level, compared to that in 2 AA section plane shown, this is rotated so that the section is made through the webs 26.

As 2 and 4 shows, a plurality of flow guide devices 20 are arranged one behind the other in a row in the channel element 12 and are oriented to one another in such a way that the flow resistance when the fluid flows through the channel 18 from the first through-opening 14 to the second through-opening 16 is particularly large, since the blocking direction and thus the passage direction of the flow guide devices 20 points in the same direction.

The backflow limiter 10 and/or the at least one flow guide device 20 are in particular designed in one piece or several flow guide devices 20 arranged one behind the other are supported on one another.

In summary, the backflow limiter 10 has a cylindrical design and can therefore be used in particular in a cylindrical hollow cross section. It is possible to line up several combinations of impact ring 22 and impact body 24 that follow one another in cross-section, with a one-piece design of this row of impact rings 22 and impact bodies 24 advantageously being implemented. In a multi-part design of this series, the individual impact rings 22 and impact bodies 24 are advantageously supported on one another.

The respective impact ring 22 is formed concavely and/or conically towards its annular opening 28 on its side facing the second through-opening, for example counter to the passage direction. Additionally or alternatively, the respective impact ring 22 has on its side associated with the first passage opening 14 an annular or peripheral groove 30 which directs at least one of the partial flows counter to the fluid flow. Additionally or alternatively, the respective impact body 24 has a conical shape in the passage direction and/or counter to the passage direction. In addition, the respective impact body 24 can advantageously also have an annular or circumferential groove 32, in particular for directing one of the partial flows counter to the flow direction of the fluid in the blocking direction at the front or counter to the passage direction at the rear.

The backflow limiter 10 shown can be designed to be particularly compact, in particular in relation to the required installation space or volume to the volume flow of the fluid that can be conducted through the backflow limiter 10 . Thus, the backflow limiter 10 or backflow preventer can be used in many different areas of application.

In particular, if a complete blocking of a fluid backflow is not important, such a backflow limiter 10 can advantageously replace conventional check valves and is cheaper and requires less maintenance, since it has no moving parts and therefore cannot wear out or become defective during normal use. Thus, an advantage of the reverse current limiter 10 is that its lifespan is virtually unlimited. In addition, it can react particularly advantageously to a high-frequency and/or pulse-like reversal of the direction of flow. In addition, particularly low-noise operation is possible, since no noise and/or vibrations occur during a closing movement.

In contrast to conventional non-return valves, there is also no shearing effect in the fluid, so that another advantage of the backflow limiter 10 is that it can also be used with sensitive liquid mixtures, such as blood in laboratory work. In addition, depending on the use of the material and the absence of moving parts, the backflow limiter 10 can also be used with particularly hot and/or aggressive fluids. Furthermore, the compact design makes it possible to save weight and/or material in a particularly advantageous manner.

With the backflow limiter shown, a Tesla valve for round bores is implemented in a particularly simple and effective manner.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102021002680 A1 [0004]

Claims (5)

Backflow limiter (10) with a channel element (12), with a first through-opening (14) which is fluidically conductively connected to a second through-opening (16) through a channel (18), wherein in the channel (18) there is at least one flow guide device (20 ) is arranged for dividing a fluid stream of a fluid flowing/flowing through the channel (18) into a plurality of directed partial streams, the partial streams being oriented/directed relative to one another in such a way that when the fluid flows through the channel (18) from the first through-opening ( 14) towards the second through-opening (16) are at least partially directed towards one another, as a result of which a flow resistance is higher than when the fluid flows in the through-flow direction through the channel (18) from the second through-opening (16) towards the first through-opening (14) , In which the partial flows are rectified and / or meet at a shallow angle, characterized in that the rest flow limiter (10) has an essentially rotationally symmetrical outer contour and the at least one flow guide device (20) consists of an essentially rotationally symmetrical impact ring (22) and an essentially rotationally symmetrical impact body (24) which is connected to the impact ring (22) by at least one radially arranged Web (26) is connected and oriented to form the partial flows is formed. Reverse current limiter (10) after claim 1 , characterized in that the outer contour of the backflow limiter (10) is cylindrical. Reverse current limiter (10) after claim 1 or 2 , characterized in that in the channel element (12) several flow guide devices (20) are arranged one behind the other and are oriented to one another in such a way that the flow resistance when the fluid flows through the channel (18) from the first passage opening (14) to the second passage opening (16) is particularly large. Backflow limiter (10) according to one of the preceding claims, characterized in that the backflow limiter (10) and/or the at least one flow guide device (20) are made in one piece or several flow guide devices (20) arranged one behind the other are supported on one another. Backflow limiter (10) according to one of the preceding claims, characterized in that the impact ring (22) is concave and/or conical in shape towards its ring opening (28) counter to the passage direction on its side facing the second through-opening (16) and/or on has a circumferential groove (30) on its side facing the first through-opening (14) and/or the impact body (24) is conically shaped in the throughflow direction and/or counter to the throughflow direction and/or has a circumferential groove on a side facing the first through-opening (14). Has groove (32).

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