Patent Application
20210138487
The invention relates to a fluidic component as per the preamble of claim 1 and to a fluid-distributing appliance which comprises a fluidic component of said type.
In fluid-distributing appliances, such as for example cleaning appliances, it is desirable to be able to generate fluid jets with different spray characteristics in order to satisfy the requirements in different fields of use. For example, there is a demand for an appliance which can selectively generate round and fan-shaped jets. It is thus possible for very stubborn dirt to be treated and cleaned in punctiform fashion with the high jet impetus of a round jet, and for sensitive surfaces to be treated and cleaned areally with the locally lower jet impetus of a fan-shaped jet (that is to say with lower output per unit of area). A fan-shaped jet or a fluid jet with a large spatial distribution of the fluid is highly suitable for rinsing purposes.
To generate a fluid jet with different spray characteristics, nozzle systems are known from the prior art in which switching back and forth between a multiplicity of nozzles, each with different spray characteristics, is realized for example by means of a slide or a rotary mechanism. Here, each nozzle has a defined and invariant spray characteristic, and fixedly predefines a jet shape for the fluid jet.
These nozzle systems generate quasistatic or static and non-oscillating fluid jets. To generate a moving fluid jet, nozzles are known from the prior art which are set in motion by means of a kinematic mechanism or a (movable) device. The kinematic mechanism or (movable) device comprises movable components which are subject to high levels of wear. The costs associated with production and maintenance are correspondingly high. Furthermore, owing to the movable components, a relatively large structural space is required overall.
To generate a movable fluid flow (or fluid jet), fluidic components are also known which generate a fluid jet which oscillates in a plane. The fluidic components comprise no movable components that serve for generating a movable fluid flow. In this way, by contrast to the nozzles with movable components, they do not have the disadvantages that result from the movable components.
The fluidic component is provided for generating a moving, oscillating or pulsing fluid jet. Examples of fluid flow patterns of an oscillating jet are sinusoidal jet oscillations, rectangular, sawtooth-shaped or triangular jet profiles, spatial or temporal jet pulsations and switching processes. Such fluid jets are used for example in order to distribute a fluid jet (or fluid flow) uniformly on a target area. The fluid flow may be a liquid flow, a gas flow, a multi-phase flow (for example wet steam) or else a fluid containing particles.
The fluidic components known from the prior art for generating a moving fluid flow generally have a fixed spray characteristic in the case of a constant volume flow and/or entry pressure of the fluid. U.S. Pat. No. 6,497,375 B1 and WO 02/07893 A1 describe fluidic components with different operating points, in the case of which, by means of closable air ingress bores, air can be conducted into the fluidic components and the oscillation can be activated and deactivated in targeted fashion. It is thus possible to switch between a spray jet with a fixed oscillation angle and a punctiform spray jet. US 2006/0065765 A1 has disclosed a device which comprises a multiplicity of fluidic components which have respectively different spray characteristics and of which selectively one fluidic component can be rotated into the fluid jet and a fluid flow with different spray characteristics can thus be generated (in a manner dependent on the selection of the fluidic component). Such a device requires a relatively large structural space overall. Furthermore, the spray characteristic of the emerging fluid flow can be varied only between a predefined number of possibilities.
The present invention is based on the object of creating a device which is designed to generate a moving fluid jet, the spray characteristic of which is settable prior to operation and/or variable during operation, wherein the device exhibits a high degree of fail safety and involves correspondingly low maintenance effort.
Said object is achieved according to the invention by means of a fluidic component having the features of claim 1. The subclaims specify embodiments of the invention.
Accordingly, the fluidic component comprises a flow chamber, which flow chamber can be flowed through by a fluid flow which enters the flow chamber through an inlet opening of the flow chamber and which exits the flow chamber through an outlet opening of the flow chamber. Preferably, the inlet opening and the outlet opening are arranged on mutually opposite sides of the flow chamber. In the flow chamber, there is provided at least one means for generating an oscillation of the fluid flow at the outlet opening. The means for generating an oscillation may for example be at least one secondary flow channel. Other means for generating an oscillation of the fluid flow may alternatively also be provided.
The fluidic component is characterized in that the flow chamber has a variable shape. For the variation of the shape of the flow chamber, it is possible in particular for a device to be provided which acts in targeted fashion on the fluidic component and thus effects a change in the shape of the flow chamber. The change in shape of the flow chamber is in this case preferably reversible. This means that the device can effect and also reverse a change in shape. For the variation of the shape of the flow chamber, various parameters of the fluidic component (or parts thereof), such as for example the shape or the volume, may be varied. In this way, a variation of the spray characteristic of the emerging fluid flow can be effected without varying the parameters of the fluid flowing through the fluidic component, such as for example the type of fluid, the entry pressure of the fluid, the entry speed of the fluid and the volume throughflow. The variation of the shape may be performed in continuously variable fashion (or optionally also in stepped fashion), such that the spray characteristic of the emerging fluid flow correspondingly also changes in continuously variable fashion (in stepped fashion) and can thus be adapted in targeted fashion to a specific application. The spray characteristic may in particular relate to the spray angle that can be set by means of the fluidic component according to the invention. Accordingly, the emerging fluid jet can be modulated between a punctiform jet and a fan-shaped jet. The fluidic component according to the invention can be used for generating a directed fluid jet with an adjustable spray characteristic for the targeted wetting, sprinkling or coating of a surface. Since, by means of the fluidic component according to the invention, the emerging fluid flow firstly performs an oscillation movement and, secondly, can be adjusted in terms of its spray characteristics, the cleaning, the surface wetting or the surface treatment performance can be massively increased. Since no movable components are used to generate the oscillation, the likelihood of failure can also be reduced. By changing the spray characteristic of the emerging fluid flow, the fluidic component can be adapted to different cleaning requirements. Thus, the fluidic component according to the invention is of interest for high-pressure, medium-pressure and low-pressure cleaning and for surface treatment and for surface coating. The variation of the shape of the flow chamber may be performed prior to commencement of operation or also during the operation of the fluidic component, that is to say while a fluid is flowing through the fluidic component.
The fluid that enters the flow chamber through the inlet opening may be charged with a pressure of 0.001 to 6000 bar (in relation to the ambient pressure). The pressure may preferably lie between 0.005 and 1800 bar. A pressure range between 0.05 and 1100 bar is especially preferred. For some applications, so-called low-pressure applications, such as for example for washing machines, dishwashers and fluid-distributing devices (sprinkler devices, handheld showers or cleaning installations), an entry pressure of 0.01 bar to 12 bar above ambient pressure is advantageous. For medium-pressure applications, such as for example high-pressure cleaning appliances with low power output, or kitchen appliances with integrated cleaning appliances, the entry pressure preferably lies between 6 bar and 120 bar above ambient pressure. In the case of high-pressure applications, the entry pressure may amount to over 40 bar. The oscillation frequency of the oscillating fluid flow emerging from the fluidic component may lie between 0.25 Hz and 40 kHz. A preferred frequency range lies between 3 Hz and 600 Hz.
The fluid may be a gaseous, liquid or multi-phase flowable medium, which may also contain particles. If the fluid is a liquid (for example water), it is advantageous for the geometry of the fluidic component to be selected such that, within the fluidic component (upstream of the outlet opening), a pressure dissipation occurs which is smaller than the pressure dissipation that occurs at the outlet opening. The geometrical parameters (shape, size, number and shape of the secondary flow channels, (relative) size of the inlet and outlet opening) of the fluidic component are in this case selected such that the pressure with which the fluid flow is charged when it enters the fluidic component via the inlet opening is substantially dissipated at the outlet opening. If the fluid is water vapor, the parameters may be selected such that the pressure with which the fluid flow is charged when it enters the fluidic component via the inlet opening is dissipated already before (upstream of) the outlet opening.
In one embodiment, the flow chamber is delimited by a delimiting wall. Here, the delimiting wall need not form the external appearance of the fluidic component. The delimiting wall may be formed by the inner surface of a hollow body, wherein the cavity of the hollow body forms the flow chamber. The external appearance of the fluidic component is then defined by the outer surface of the hollow body. The outer surface of the hollow body may in particular be substantially cuboidal and have interruptions for the inlet opening and the outlet opening.
The flow chamber may have a main flow channel, which connects the inlet opening and the outlet opening to one another, and at least one secondary flow channel, as a means for generating an oscillation of the fluid flow at the outlet opening. The direction from the inlet opening to the outlet opening may in this case be regarded as the main flow direction of the fluid flow. Here, the main flow channel and the at least one secondary flow channel may be separated from one another by at least one inner block, such that the main flow channel, the at least one inner block and the at least one secondary flow channel are arranged substantially in a plane. The emerging fluid flow then oscillates in an oscillation plane which corresponds to the plane which is defined by the main flow channel, the at least one inner block and the at least one secondary flow channel. In particular, the flow chamber may have two secondary flow channels which lie in a plane with the main flow channel, wherein the main flow channel lies between the two secondary flow channels (as viewed transversely with respect to the main flow direction). In this case, each secondary flow channel is separated from the main flow channel by at least one inner block. The secondary flow channels may each have one entrance and one exit, via which said secondary flow channels are fluidically connected to the main flow channel.
In order to be able to vary the shape of the flow chamber, the delimiting wall may, in one embodiment, have at least one portion which is deformable. For this purpose, the at least one portion may have different material characteristics, such as for example material thickness or extensibility (elasticity), in relation to the rest of the delimiting wall. The at least one deformable portion of the delimiting wall can then be deformed under targeted action of an external force.
A targeted action of an external force is in particular not to be understood to mean the pressure of the fluid flowing through the fluidic component. Rather, a device for imparting the external force may be provided, which device is actuatable by a user. This likewise applies to the other embodiments.
As an alternative to the abovementioned targeted action of an external force, an internal force that results substantially from the pressure of the fluid flowing through the fluidic component may be utilized to deform the at least one deformable (for example elastic) portion of the delimiting wall in targeted fashion. Here, the at least one deformable portion may be designed such that it is reversibly deformable as a result of action of the internal force, that is to say changes from a first into a second configuration in the event of an increase of the mass flow at the inlet opening (of the entry pressure) and returns from the second into the first configuration in the event of a drop of the mass flow at the inlet opening (of the entry pressure). The transition between more than two configurations, or a continuously variable transition, is also conceivable. In particular, by means of the deformation, dependent on the mass flow, of the at least one deformable portion of the delimiting wall, and in a manner dependent on the physical position of the at least one deformable portion, a virtually constant pressure and/or volume flow can be set in the flow chamber and in particular at the outlet opening. In this way, the fluidic component can be made into a so-called self-regulating system which, despite varying admission pressure or fluid entry pressure, exhibits a virtually constantly high volume flow at the outlet opening and generates a virtually invariant droplet spectrum. Here, in the event of increasing (decreasing) pressure at the inlet opening, the spray angle of the emerging fluid flow may remain virtually constant or decrease (increase). For example, the at least one deformable portion of the delimiting wall may be formed as an elastically deformable wall which delimits the outlet opening (transversely with respect to the fluid flow direction) and which deforms in the event of a change in the fluid pressure at the outlet opening and, in so doing, changes the cross-sectional area of the outlet opening to such an extent that the resulting droplet sizes of the emerging fluid flow are scarcely dependent on the admission pressure, and that the pressure at the outlet opening substantially returns to the previously prevailing level, or remains at said level. In other words, in the case of the self-regulating system, in relation to a virtually rigid, non-variable system, the Sauter diameter of the droplets of the emerging fluid flow decreases to a lesser extent with increasing entry pressure, or remains virtually stable despite an increasing entry pressure.
The material of the at least one deformable portion of the delimiting wall must in this case be selected such that it does not deform in the presence of an arbitrary pressure of the fluid which flows through the fluidic component and which exerts the so-called internal force on the at least one deformable portion, but rather deforms only in a predetermined pressure range or pressure change range. The fluidic component according to the invention can be used for various applications in which, firstly, the dimensions of the fluidic component and, secondly, the volume flow that is to be provided at the outlet opening may vary to a greater or lesser extent. In particular, the narrowest point of the fluidic component through which flow can pass plays a role in terms of the dimensioning. The narrowest point of a fluidic component through which flow can pass is, as viewed in a fluid flow direction, to be understood to mean that point (outside the secondary flow channels) at which the fluidic component has its smallest cross-sectional area extending substantially transversely with respect to the fluid flow direction. The narrowest point may in this case be formed by the inlet opening, the outlet opening or by a point in the main flow channel at which the distance (transversely with respect to the fluid flow direction) between the inner blocks is at its smallest.
Fluidic components for cleaning, wetting, coating or rinsing applications may, at their narrowest point, have a cross-sectional area of 0.005 mm2 to 200 mm2. For special applications with low throughflow rates, the narrowest point may have a cross-sectional area of 0.005 mm2 to 5 mm2. In the agricultural sector and for sprinkling tasks, the fluidic component may have a narrowest point with a cross-sectional area of 0.01 mm2 to approximately 30 mm2. Typical entry pressures for the fluid in this application sector (cross-sectional area of 0.01 mm2 to approximately 30 mm2) are 0.25 bar to 16 bar above ambient pressure. For uses of the fluidic components for low-pressure cleaning, entry pressures of 1 bar to 60 bar above ambient pressure are common, wherein the narrowest point may have a cross-sectional area of 0.3 mm2 to 200 mm2. For uses of the fluidic components for high-pressure cleaning, pressures of 40 bar to approximately 1500 bar above ambient pressure may be used, wherein the narrowest point may assume a cross-sectional area of 0.5 mm2 to 180 mm2.
In a self-regulating nozzle system which, despite changes in the entry pressure (of the fluid flow entering the fluidic component at the inlet opening), provides a virtually constant volume flow at the outlet opening, the at least one deformable portion of the delimiting wall may be arranged so as to delimit the inlet opening and/or the outlet opening or so as to permit a movement of a movable part of the delimiting wall, wherein the movement leads to a change in the cross-sectional area of the inlet opening and/or of the outlet opening. Accordingly, by means of the physical orientation of the movable part of the delimiting wall, it is possible to determine whether the movement of the movable part of the delimiting wall owing to a deformation (expansion as a result of an increase of the entry pressure) of the at least one deformable portion increases or decreases the cross-sectional area. In addition or alternatively, the inner blocks may have at least one deformable portion at or close to that point in the main flow channel at which the distance (transversely with respect to the fluid flow direction) between the inner blocks is at its smallest, such that a change in the cross-sectional area of this point in the main flow channel is possible. As a material for said at least one deformable portion (of the delimiting wall or of the inner blocks), a material may be used which can expand or contract in accordance with the pressure changes in order to change the size of the cross-sectional areas.
For a fluidic component with a resistance coefficient of 0.89 and a narrowest point (inlet opening, outlet opening or point in the main flow channel) with a cross-sectional area of approximately 0.75 mm2, the material should be deformable such that, in the event of a pressure drop by a factor of 100, said cross-sectional area increases in size by a factor of 10. If, in this fluidic component, the pressure at the inlet opening conversely increases by a factor of 100 (for example from 3 bar to 300 bar), said cross-sectional area should decrease in size by a factor of 10 (from approximately 0.75 mm2 to approximately 0.075 mm2). The extent of the variation of the cross-sectional area is in particular dependent on the (partially pressure-dependent) resistance coefficient of the fluidic component.
A self-regulating nozzle system may also be designed such that, in the case of varying volume flows at the narrowest point (inlet opening, outlet opening or point in the main flow channel) caused by varying entry pressures, the same pressure dissipation occurs within the fluidic component. For this purpose, in the case of increasing volume flow, the cross-sectional area of the narrowest point should increase in size. For example, the cross-sectional area (1 mm2) increases in size by approximately 14% if, at the narrowest point, the volume flow increases from 1.4 l/min to 1.6 l/min.
For the change in the size of the cross-sectional area of the narrowest point, it is for example possible to utilize geometrical non-linearities, elastically deformable portions of the delimiting wall or of the inner blocks (similarly to the case of flexure hinges), or the so-called fin-ray effect. The increase of the entry pressure can result in an increased (internal) force acting on the delimiting wall and on the inner blocks. Said force provides for a reversible (elastic) deformation of a portion of the wall, which, depending on operating principle, then provides for a deformation of another portion of the wall. A change in the throughflow may furthermore be achieved by means of an adaptation of the pressure loss coefficient. To increase the cross-sectional area of the narrowest point, the wall portion that delimits the narrowest point may be designed so as to elastically or reversibly deform said wall portion in a manner dependent on the increasing pressure, for example by means of the elasticity (flexibility) of the material.
In a further embodiment, the at least one deformable portion of the delimiting wall may form a portion of the at least one secondary flow channel. In the case of two secondary flow channels, two such deformable portions may be provided, such that the two secondary flow channels may be of similar construction. The deformable portion may be designed such that the cross-sectional area of the one or more secondary flow channels can be locally varied (reduced) by deformation of the portion. In this way, in the case of compressible fluids, it is possible in particular for the oscillation frequency of the emerging fluid flow to be varied. In this way, it is furthermore possible for a fan-shaped jet to be generated which is oriented substantially orthogonally with respect to the oscillation plane. As an alternative to the deformation of the delimiting wall in the region of the secondary flow channel, the cross-sectional area of the secondary flow channel may be varied by means of a slide, which can be introduced in targeted fashion into the secondary flow channel. The cross-sectional variation may also be realized by means of a bolt or a threaded rod which can be screwed into the secondary flow channel.
It is furthermore possible for the delimiting wall to comprise at least two parts, wherein one of the two parts is movable relative to the other of the two parts. The movement may in this case be a displacement or a rotation. Here, the axis of rotation may in particular be oriented perpendicular to the oscillation plane. However, the angle between the oscillation plane and the axis of rotation may also deviate from 90°. The displacement may in particular take place in the oscillation plane. However, a displacement that takes place at an angle with respect to the oscillation plane (for example 90°) is conceivable.
In one embodiment, the flow chamber has an outlet channel (directly) upstream of the outlet opening. At its downstream end, the outlet channel opens into the outlet opening. In particular, the outlet channel may be formed so as to be free from obstructions, that is to say no elements which impede or influence the fluid flow are arranged in the outlet channel. As viewed in the oscillation plane, the outlet channel narrows in a downflow direction along the main flow direction. To form the outlet channel, two portions of the delimiting wall above and below the oscillation plane extend substantially parallel to the oscillation plane. These two portions are connected to one another by a further two portions of the delimiting wall, which extend substantially perpendicular to the oscillation plane and which enclose an angle with one another in the oscillation plane. The portions of the delimiting wall that form the outlet channel may be formed together as a single piece. It is also possible for the outlet channel to be formed as a single piece with the rest of the delimiting wall, which forms the rest of the flow chamber. Here, the outlet opening constitutes an interruption of the delimiting wall.
However, the two portions of the delimiting wall that extend substantially perpendicular to the oscillation plane and are part of the outlet channel may be formed as two movable parts (portions) of the delimiting wall which are movable relative to a third part of the delimiting wall (the rest of the outlet channel, the remaining flow chamber or the rest of the delimiting wall).
These two movable parts of the delimiting wall may be rotatable relative to the third part of the delimiting wall. Here, each of the two movable parts may be rotatable independently of the other of the two movable parts relative to the third part of the delimiting wall. Here, the axis/axes of rotation may extend substantially perpendicular to the oscillation plane. By means of the rotation of these two movable parts of the delimiting wall, the angle between the two movable parts of the delimiting wall in the oscillation plane can be varied. This can lead to a variation of the oscillation angle of the emerging fluid flow. Depending on the position of the axes of rotation (in particular the distance thereof to the outlet opening (as viewed in the oscillation plane)), the width of the outlet opening can also be varied by means of the rotation of the two movable parts of the delimiting wall. Here, the width of the outlet opening is the extent of the outlet opening perpendicular to the main flow direction within the oscillation plane. The further remote from the outlet opening the axes of rotation are, the greater the extent to which the width of the outlet opening also changes in the event of a rotation of the two movable parts of the delimiting wall. A variation of the width of the outlet opening can lead to a change in the jet impetus and in the pressure loss at the outlet opening. By means of a reduction of the outlet width, the jet impetus can be increased in the case of an unchanging internal pressure, which can lead to an increase in the cleaning performance by means of the focusing of the jet force. To minimize the coupling between the change in the angle and the outlet width, the axes of rotation may be provided as close as possible to the outlet opening. In order to primarily change the angle between the two movable parts of the delimiting wall without simultaneously influencing the outlet width, an eccentric may be provided instead of an axis of rotation. In the extreme case, it is possible to keep the outlet width constant while said angle is varied.
These two movable parts of the delimiting wall may also be displaceable relative to the third part of the delimiting wall. The displacement may in particular take place in the oscillation plane. Here, the displacement may take place such that the outlet width but not the angle between the two movable parts of the delimiting wall is varied. For example, the displacement may take place along the width of the outlet opening or along those axes in which the planes spanned by the two movable parts of the delimiting wall and the oscillation plane intersect. In the latter case, the width of the outlet opening changes without the cross-sectional area of the secondary flow channel at the entrance of the secondary flow channel being varied. In both cases, the width of the emerging fluid jet can be varied. In one advantageous embodiment, the width of the outlet opening can be varied approximately to the value zero. Alternatively, for the purposes of changing the outlet width, an aperture-like device may be provided which is arranged in the region of the outlet opening and which extends substantially transversely with respect to the main flow direction of the fluid flow. By means of such an aperture, the outlet opening can be varied, in particular reduced in size. Furthermore, a displacement of these two movable parts of the delimiting wall can be performed along the main flow direction in the direction of the inlet opening. Here, the cross-sectional area of the entrance of the at least one secondary flow channel can be reduced. By means of this measure, the oscillation mechanism can be reduced or rendered inactive, such that the emerging fluid jet can be varied between an oscillating fluid jet and a compact, straight fluid jet (or a fluid jet similar to an orifice nozzle).
It is furthermore conceivable for the displacement to take place along the main flow direction of the fluid flow away from the inlet opening. Here, the width of the outlet opening and the angle between the two separate parts of the delimiting wall, which are part of the outlet channel, do not change, but the volume of the outlet channel does change. This can have the effect that the oscillation angle varies only slightly, while the oscillation frequency and the profile with respect to time of the emerging fluid jet vary to a greater extent.
In order to be able to move (rotate or displace) the two movable parts of the delimiting wall relative to the third part of the delimiting wall, a device may be provided which can be actuated by a user. The movement of the two separate parts may in particular take place in a mutually independent manner. Thus, the angle at which the fluid flow emerges from the fluidic component can be varied.
For example, one of the two parts may be moved downstream and the other of the two parts may be moved upstream. Consequently, the angle at which the fluid flow emerges from the fluidic component is diverted in the direction of the part that has been moved upstream.
In one advantageous embodiment, the delimiting wall that forms the outlet channel is manufactured from a different, specifically a harder or more wear-resistant, material than the rest of the delimiting wall. Accordingly, the delimiting wall that forms the outlet channel may be formed from a ceramic material, whereas the rest of the delimiting wall is manufactured from a rust-resistant steel.
In a further embodiment, for the purposes of changing the shape of the flow chamber (and thus for the purposes of changing the spray characteristic of the emerging fluid flow), the at least one inner block may be deformable and/or movable relative to the delimiting wall. In this way, the shape and the volume of the main flow channel and/or of the at least one secondary flow channel can be influenced. By means of this variation, the oscillation angle and the oscillation frequency and the behavior of the emerging fluid jet with respect to time can be varied. The movement may be a rotational movement (about an axis of rotation that extends substantially perpendicular to the oscillation plane) or a displacement (within the oscillation plane). An eccentric may also be provided instead of an axis of rotation.
The at least one inner block may be formed in two parts, such that one part of the inner block is movable relative to the other part of the inner block, or the two parts of the inner block are movable independently of one another relative to the delimiting wall. By movement of the two parts of the at least one inner block with respect to one another, it is for example possible for the shape of the main flow channel to be changed, without influencing the at least one secondary flow channel in the process, and vice versa. Here, a gap or a channel may form between the two parts. The division of the at least one inner block into the two parts may in this case be provided such that the gap formed as a result of the movement does not connect the main flow channel and the at least one secondary flow channel to one another, but rather the gap that forms extends through the at least one inner block from the entrance of the at least one secondary flow channel to the exit of the at least one secondary flow channel. In this way, a leakage flow between the main flow channel and the at least one secondary flow channel is avoided.
In a further embodiment, the at least one inner block may have a channel which extends through the at least one inner block such that the channel fluidically connects the main flow channel and the at least one secondary flow channel to one another. Here, the at least one inner block need not imperatively be constructed in two parts. The channel may also extend in the manner of a pipe through the at least one inner block. By means of the described orientation of the channel from the main flow channel to the at least one secondary flow channel, an additional fluid connection between the main flow channel and the at least one secondary flow channel is provided in a targeted manner. The channel may function as an additional secondary flow channel and thus influence the spray characteristic of the emerging fluid flow. In particular, provision may be made for the channel and/or the at least one secondary flow channel to be closable. It is thus possible for selectively either the channel or the at least one secondary flow channel to be closed, such that the other of the two can be passed through by the fluid and influences the generation of the oscillation.
In one embodiment, the fluidic component has a component length, a component width and a component depth. Here, the component length is defined along a direction which extends substantially from the inlet opening to the outlet opening (the main flow direction of the fluid flow). The component width and the component depth are each defined perpendicularly with respect to one another and with respect to the component length.
In the case of a substantially cuboidal fluidic component, the ratio of component length to component width may amount to 1/3 to 5/1. The ratio preferably lies in the range from 1/1 to 4/1. The component width may lie in a range from 0.1 mm to 1.75 mm. In a preferred design variant, the component width lies between 1.5 mm and 300 mm. The stated dimensions are in particular dependent on the use for which the fluidic component is intended. For example, for cleaning showers in the low-pressure range, the component width typically lies between 4 mm and 50 mm.
The extent of the flow chamber along the component length, the component depth or the component width may be variable. In this way, it is possible in particular for the volume of the flow chamber to be changed. With increasing component length, the jet profile with respect to time can be approximated to a rectangular function. By means of a further lengthening of the component length, the oscillation angle can be reduced, as far as the limit case in which a quasistatic orifice jet is realized.
The delimiting wall may, for the purposes of changing the component length, depth or width, be of telescopic or bellows-like form. Here, it is also possible for the length, depth or width of the at least one inner block to be variable (by means of a telescopic or bellows-like construction). Here, the delimiting wall and the at least one inner block can be varied independently of one another. In one advantageous embodiment, either the length of the at least one inner block or the length of the flow chamber is varied.
A change of the component length may take place in particular in the region of the outlet channel. This means that the outlet channel can, with shortening of the component length by means of a telescopic construction, be moved in the direction of the inlet opening along the main flow direction or, with lengthening of the component length, be moved away from the inlet opening along the main flow direction.
The outlet opening may be adjoined, downstream, by an outlet widening. The outlet widening may comprise two portions of the delimiting wall which extend substantially perpendicular to the oscillation plane. These two portions may be formed so as to be movable relative to the rest of the delimiting wall. Here, the two movable portions of the delimiting wall may be oriented so as to enclose an angle in the oscillation plane, wherein the outlet widening widens in a downstream direction along the width of the outlet opening. Here, the angle between the two movable portions of the delimiting wall, which are part of the outlet widening, may be variable. For this purpose, the movable portions may be rotatable about an axis which extends substantially perpendicular to the oscillation plane. By means of a change in the angle between the movable portions, the oscillation angle of the emerging fluid flow can be varied. The outlet widening should have a length (along the component length) which is at least 25% of the width of the outlet opening. By means of the outlet widening, the spray jet is guided within the oscillation plane, which leads to an increase of the spray impetus.
An outlet channel may be provided upstream of the outlet opening, and an outlet widening may be provided downstream of the outlet opening. Here, the outlet opening may form the transition between the outlet channel and the outlet widening. The transition may in particular be formed by a radius. A radius is to be understood here to mean a circular arc of a circular portion. In one embodiment, the magnitude of the radius in the oscillation plane is variable. If the radius is equal to zero, then the outlet opening is formed by a sharp edge. By enlargement of the radius, the droplet spectrum can be shifted in the direction of smaller droplets. In the event of a change in the radius, it is in particular possible for the shape of the outlet channel that adjoins the outlet opening in an upstream direction and/or the shape of the outlet widening that adjoins the outlet opening in a downstream direction to also change. Furthermore, the width of the outlet opening (that is to say the extent thereof in the oscillation plane transversely with respect to the fluid flow direction) can be changed simultaneously with the change in the radius. By means of a change in the radius, not only the droplet spectrum but also the spray angle and/or the fluid distribution within the spray fan of the emerging fluid flow can be varied. The radius may also be changed into some other rounded shape, which may be constituted for example by a polygon. Here, the abovementioned angle of the outlet widening may also change.
For the change in the radius, it is for example possible for a plunger device to be provided, which plunger device is integrated into a wall, which extends parallel to the oscillation plane, of the fluidic component and which plunger device can be displaced perpendicularly with respect to the oscillation plane. The plunger device may have a multiplicity of shapes for the purposes of configuring the radius of the outlet opening, which shapes can be moved into the oscillation plane as required.
Alternatively, for the purposes of changing the radius, provision may be made whereby, in the region of the outlet opening and possibly in the adjoining region of the outlet channel and/or of the outlet widening, the material of the respective wall (which extends substantially perpendicular to the oscillation plane) is elastically deformable. For this purpose, the elastic material may have a spring sheet or an elastic plastic. For the deformation of the elastic material, a body which is displaceable in the oscillation plane may be provided, which body can, by displacement, exert a force on the elastic material and thus effect a deformation of the elastic material, changing the radius of the outlet opening.
The angle enclosed by the walls of the outlet widening which adjoins the outlet opening in a downstream direction, which walls extend substantially perpendicular to the oscillation plane, may be changed simultaneously with the change in the radius. The change in angle may be realized, with deformation of the elastically deformable material in the region of the outlet widening which adjoins the outlet opening, by means of an action of force, or displacement, of a body transversely with respect to or in the oscillation plane. Depending on the physical embodiment of the flow chamber of the fluidic component, the spray angle of the fluid jet can be changed by means of the change in angle of the outlet widening and the change in radius of the outlet opening. Thus, by enlargement of the radius, the fraction of relatively small droplets in the emerging fluid flow can be increased, and thus the Sauter diameter of the droplets can be reduced, which is advantageous for example for wetting and coating processes.
In a further embodiment, the inlet opening may have a variable width. Here, the width of the inlet opening is defined substantially perpendicularly with respect to the main flow direction of the fluid flow within the oscillation plane. By means of a variation of the width of the inlet opening, the spray characteristic of the emerging fluid flow can be set between a virtually punctiform jet and an oscillating fluid jet, wherein the oscillating fluid jet may be regarded as a fan-shaped jet. It is thus for example possible for the output per unit of area of the fluidic component to be set in accordance with the field of use.
In a further embodiment, the flow chamber has at least two secondary flow channels connected in parallel as means for generating an oscillation of the fluid flow at the outlet opening. Here, the at least two secondary flow channels connected in parallel have different shapes. At a given point in time, only one of the at least two secondary flow channels connected in parallel can be flowed through by the fluid flow. This means that the at least two secondary flow channels connected in parallel cannot be flowed through simultaneously by the fluid flow. Depending on the desired profile of the emerging fluid flow, a secondary flow channel with a particular shape may be selected for the throughflow. In order to close the secondary flow channels, a displaceable partition may be provided which, by means of a closing mechanism, can be pushed transversely with respect to the fluid flow direction into a secondary flow channel so as to close the secondary flow channel over the entire cross section. Here, provision may be made whereby, when one (specifically exactly one) of the at least two secondary flow channels connected in parallel is opened up, the one or more others of the at least two secondary flow channels connected in parallel is or are simultaneously closed.
The at least two secondary flow channels connected in parallel form a unit. For example, the fluidic component may comprise two such units, wherein the main flow channel is arranged for example between the two units. In this case, always two secondary flow channels are opened up for the throughflow, wherein the two secondary flow channels belong to in each case one unit.
A unit may for example comprise two secondary flow channels connected in parallel. There may however also be more than two. The secondary flow channels, connected in parallel, of a unit may be arranged in a plane, which for example corresponds to the oscillation plane. However, the secondary flow channels connected in parallel may, in order to save space, be arranged in different planes. This arrangement may be of particular interest if a unit comprises more than two secondary flow channels connected in parallel, or if a relatively long secondary flow channel is provided.
Through selection of the shape of a secondary flow channel, and in particular by means of a change in the length of a secondary flow channel, the oscillation frequency of the emerging fluid flow can be varied. If, for example, a switch is made from a relatively short secondary flow channel to a relatively long secondary flow channel, the oscillation frequency is reduced.
The at least one secondary flow channel or the at least two secondary flow channels connected in parallel may have each one entrance and each one exit and may extend between the respective entrance and the respective exit. Here, said entrance and exit constitute the transition at which the main flow channel is fluidically connected to the secondary flow channels. In one embodiment, in the region of at least one entrance and/or of at least one exit, one or more elements project into the flow chamber such that it/they can be flowed around by the fluid flow. Here, the at least one element is adjustable in position within the region of the at least one entrance and/or of the at least one exit. For the adjustment of the position, an adjusting device may be provided which is suitable for adjusting the at least one element (in continuously variable fashion). Here, the at least one element may be displaceable in the oscillation plane or may be rotatable about an axis which extends substantially perpendicular to the oscillation plane. Here, the axis of rotation may run through the center of the respective element, or eccentrically. The adjustability of the position is in this case restricted to the at least one element remaining in the region of the respective entrance or exit. In particular, the at least one element is not adjustable such that it passes into the outlet channel situated upstream of the outlet opening. Alternatively or in addition, the at least one element may be adjustable in terms of its position such that it is movable (by means of a translational or screwing movement), in the manner of a plunger, into the flow chamber transversely with respect to the oscillation plane. For this purpose, the corresponding front or rear wall, which delimits the flow chamber, of the fluidic component may be of elastic form in certain portions. Thus, the at least one element can be adjustable (in continuously variable fashion) between two maximum deflections, at which the at least one element either extends over the entire depth of the fluidic component or does not project into the flow chamber at all.
The at least one element may have various shapes. For example, it may (as viewed in the oscillation plane) have a circular, elliptical, sickle-shaped or polygonal cross section, or mixed forms of these. Here, a rotatable element has in particular a rotationally asymmetrical shape. If multiple elements are provided, these may differ in terms of shape and/or adjustability (translation, rotation). By changing the position of the at least one element, the jet characteristic of the fluid flow emerging from the fluidic component can be changed. By means of the at least one adjustable element, the flow is influenced to such an extent that the spray angle and/or the profile with respect to time of the emerging fluid flow change(s).
The at least one element extends preferably over the entire depth of the fluidic component, that is to say over the entire extent of the fluidic component perpendicular to the oscillation plane. However, the at least one element may extend only over a portion of the depth.
In a further embodiment, the fluidic component has at least two secondary flow channels, which can be flowed through simultaneously by a fluid flow. Here, each of the at least two secondary flow channels has an opening. Via the openings, the at least two secondary flow channels are connected to a connecting channel, which is designed to be closable. To close the connecting channel, at least one partition may be provided which is movable into the connecting channel and out of the latter again. In particular, multiple partitions may be provided which correspond in number to the number of openings of the at least two secondary flow channels. Here, the partitions may be arranged respectively in the region of an opening of the at least two secondary flow channels in order to close or open up the openings. If the connecting channel is not closed, it fluidically connects the at least two secondary flow channels to one another. In this way, the oscillation frequency of the emerging fluid flow (and thus the shape of the spray fan) are reduced, and the spray angle is influenced. If the connecting channel is closed, the fluid flows only through the at least two secondary flow channels and the main flow channel.
The various embodiments of the fluidic component may also be combined with one another in order to realize a desired spray characteristic.
The movement or deformation of individual elements of the fluidic component (for the purposes of deforming the flow chamber) is realized in all embodiments by means of a device which exerts a force on the corresponding element in targeted fashion and thereby effects the movement or deformation respectively. Said device is designed to reverse the movement or deformation respectively.
The invention furthermore relates to a fluidic assembly as per the preamble of claim 19. Accordingly, the fluidic assembly comprises the fluidic component according to the invention and a sealing body into which the fluidic component is embedded. Here, the sealing body seals off the entire fluidic component with the exception of the inlet opening and the outlet opening of the fluidic component. By means of the sealing body, it can be achieved that, in the event that a leak arises during a variation of the shape of the flow chamber, the fluid cannot enter the flow chamber or exit the flow chamber outside the inlet opening and the outlet opening. The sealing body may comprise a flexible material, for example a flexible plastics material, which is suitable for deforming, in particular expanding, in the event of a corresponding variation of the shape of the flow chamber.
The invention furthermore relates to a fluid-distributing appliance which comprises the fluidic component according to the invention or the fluidic assembly according to the invention. The fluid-distributing appliance may in particular be a cleaning appliance or a watering appliance. The watering appliance may be used for example in irrigation systems, lawn sprinklers or handheld showers.
The invention will be discussed in more detail below on the basis of exemplary embodiments in conjunction with the drawings, in which:
The flow chamber 10 comprises an inlet opening 101, via which the fluid flow enters the flow chamber 10, and an outlet opening 102, via which the fluid flow emerges from the flow chamber 10. The inlet opening 101 and the outlet opening 102 are arranged on two sides of the fluidic component 1, which are situated oppositely (in terms of flow), between a front wall 12 and a rear wall 13. The front wall 12 and the rear wall 13 are a part of the delimiting wall 5 of the flow chamber 10. The fluid flow 2 moves in the flow chamber 10 substantially along a longitudinal axis A of the fluidic component 1 (which connects the inlet opening 101 and the outlet opening 102 to one another) from the inlet opening 101 to the outlet opening 102. The inlet opening 101 has an inlet width bIN and the outlet opening 102 has an outlet width bEX. The widths are defined, in the oscillation plane, substantially perpendicularly with respect to the longitudinal axis A.
The flow chamber 10 comprises a main flow channel 103 which extends centrally through the fluidic component 1. The main flow channel 103 extends substantially rectilinearly along the longitudinal axis A, such that the fluid flow in the main flow channel 103 flows substantially along the longitudinal axis A of the fluidic component 1. At its downstream end, the main flow channel 103 transitions into an outlet channel 107, which narrows in a downstream direction as viewed in the oscillation plane and ends in the outlet opening 102.
To generate an oscillation of the fluid flow at the outlet opening 102, the flow chamber 10 comprises, by way of example, two secondary flow channels 104a, 104b, wherein the main flow channel 103 is arranged (as viewed transversely with respect to the longitudinal axis A) between the two secondary flow channels 104a, 104b. Directly downstream of the inlet opening 101, the flow chamber 10 divides into the main flow channel 103 and the two secondary flow channels 104a, 104b, which are then merged upstream of the outlet opening 102. The two secondary flow channels 104a, 104b are in this case, by way of example, of identical shape and arranged symmetrically with respect to the longitudinal axis A (
Proceeding from the inlet opening 101, the secondary flow channels 104a, 104b, in a first portion, each initially extend in opposite directions at an angle of substantially 90° with respect to the longitudinal axis A. The secondary flow channels 104a, 104b subsequently bend such that they each extend substantially parallel to the longitudinal axis A (in the direction of the outlet opening 102) (second portion). In order to merge the secondary flow channels 104a, 104b and the main flow channel 103 again, the secondary flow channels 104a, 104b change their direction once again at the end of the second portion, such that said secondary flow channels are each directed substantially in the direction of the longitudinal axis A (third portion). In the embodiment of
The secondary flow channels 104a, 104b are a means for influencing the direction of the fluid flow that flows through the flow chamber 10, and ultimately a means for generating an oscillation of the fluid flow at the outlet opening 102. For this purpose, the secondary flow channels 104a, 104b have each one entrance 104a1, 104b1, which is formed by that end of the secondary flow channels 104a, 104b which faces toward the outlet opening 102, and each one exit 104a2, 104b2, which is formed by that end of the secondary flow channels 104a, 104b which faces toward the inlet opening 101. A small part of the fluid flow, the secondary flows, flows through the entrances 104a1, 104b1 into the secondary flow channels 104a, 104b. The remaining part of the fluid flow (the so-called main flow) exits the fluidic component 1 via the outlet opening 102. The secondary flows emerge from the secondary flow channels 104a, 104b at the exits 104a2, 104b2, where they can impart a lateral impetus (transversely with respect to the longitudinal axis A) on the fluid flow entering through the inlet opening 101. Here, the direction of the fluid flow is influenced such that the main flow emerging at the outlet opening 102 spatially oscillates, specifically in a plane, the so-called oscillation plane, in which the main flow channel 103 and the secondary flow channels 104a, 104b are arranged. The oscillation plane is parallel to the main extent plane of the fluidic component 1. The moving emerging fluid jet oscillates within the oscillation plane with the so-called oscillation angle.
In an alternative which is not illustrated, it is possible instead of the secondary flow channels to use other means for generating the oscillation of the emerging fluid jet. Examples for this are edges which extend into the flow chamber 10, or steps which are visible to the fluid flow, in order to thus generate a periodically detaching flow within the component 1. To intensify this periodically oscillating flow, the flow chamber 10 is shaped such that so-called recirculation areas can alternately build up and dissipate within this flow chamber. It is also possible for the secondary flow channels to be arranged asymmetrically with respect to the longitudinal axis A. Furthermore, the secondary flow channels may also be positioned outside the illustrated oscillation plane. Said channels may for example be realized by hoses outside the oscillation plane, or by channels which run at an angle with respect to the oscillation plane.
In the design variant illustrated here, the secondary flow channels 104a, 104b each have a cross-sectional area which is virtually constant over the entire length (from the entrance 104a1, 104b1 to the exit 104a2, 104b2) of the secondary flow channels 104a, 104b. In a design variant which is not illustrated here, the cross-sectional areas may be non-constant. By contrast, the size of the cross-sectional area of the main flow channel 103 increases substantially steadily in the flow direction of the main flow (that is to say in the direction from the inlet opening 101 to the outlet opening 102).
The main flow channel 103 is separated from each secondary flow channel 104a, 104b by an inner block 11a, 11b. In the embodiment from
At the entrance 104a1, 104b1 of the secondary flow channels 104a, 104b, there are provided separators 105a, 105b in the form of indentations (into the flow chamber). From the perspective of the flow, the separators are protuberances. Here, at the entrance 104a1, 104b1 of each secondary flow channel 104a, 104b, respectively one indentation 105a, 105b projects beyond a portion of the circumferential edge of the secondary flow channel 104a, 104b into the respective secondary flow channel 104a, 104b and, at this location, changes the cross-sectional shape thereof, with a decrease in size of the cross-sectional area. In
Positioned upstream of the inlet opening 101 of the flow chamber 10 is a funnel-shaped extension 106 which (in the oscillation plane) narrows in the direction of the inlet opening 101 (in the downstream direction). Also, upstream of the outlet opening 102, the flow chamber 10 narrows (in the oscillation plane). The narrowing is formed by the abovementioned outlet channel 107, which extends between the entrances 104a1, 104b1 of the secondary flow channels 104a, 104b and the outlet opening 102. In
The outlet channel 107 is formed by portions of the delimiting wall 5. Here, two portions of the delimiting wall 5 are perpendicular to the oscillation plane and enclose an angle δ in the oscillation plane. These two portions are each formed as planar surfaces. Alternatively, these two portions may be formed by curved surfaces.
The inlet opening 101 and the outlet opening 102 each have a rectangular cross-sectional area (transversely with respect to the longitudinal axis A). These each have the same depth t but differ in terms of their width bIN, bEX. Alternatively, a non-rectangular cross-sectional area is also conceivable for the inlet opening 101 and the outlet opening 102.
The distance between the inlet opening 101 and the outlet opening 102 (the component length l) may have a ratio to the component width b of 1/3 to 4/1, preferably of 1/1 to 4/1. The component width b may lie in the range from 0.1 mm to 1.75 m. In a preferred design variant, the internal component width bi lies between 1.5 mm and 150 mm. The width bEX of the outlet opening 102 amounts to 1/3 to 1/50 of the component width b, preferably 1/5 to 1/20. The width bEX of the outlet opening 102 is selected in a manner dependent on the volume throughflow, the component depth t, the entry speed of the fluid and/or the entry pressure of the fluid, and the desired oscillation frequency. The width bIN of the inlet opening 101 amounts to 1/3 to 1/30 of the component width b, preferably 1/5 to 1/15.
In
The outlet widening 108 is formed by portions of the delimiting wall 5. Here, two portions 53a, 53b of the delimiting wall 5 are perpendicular to the oscillation plane and enclose an angle ε in the oscillation plane. Said two portions 53a, 53b are each formed as planar surfaces. Alternatively, said two portions may be formed by curved surfaces. The angle ε may have different values. In particular, the angle ε may be set in a manner dependent on the desired oscillation angle of the fluid flow. Preferably, the angle ε is greater than the oscillation angle of the fluid flow by at least 8° in order to obtain a fluid jet which moves in an undisrupted manner. In order to obtain a defined oscillation angle or in order to restrict the oscillation angle, an angle ε less than or equal to the oscillation angle of the freely oscillating fluid jet (without outlet widening) is advantageous.
The outlet opening 102 defines the transition between the outlet channel 107 and the outlet widening 108. The transition may be formed by a radius 109. Said radius 109 is preferably smaller than the width bIN of the inlet opening 101 or the width b103 of the main flow channel 103 at its narrowest point in the oscillation plane. Here, the narrowest point of the main flow channel 103 in the oscillation plane is the point at which the distance between the inner blocks 11a, 11b in the oscillation plane and transversely with respect to the longitudinal axis A is at its smallest. If the radius 109 is equal to 0, then the outlet opening 102 is sharp-edged. However, owing to the greater mechanical stability, a radius 109 with a value greater than zero is preferred.
As per
On the basis of the fluidic component 1 illustrated in
With regard to the possibilities, illustrated in
The fluidic component 1 from
As an alternative to the embodiment from
The movable portions 51a, 51b in the embodiment of
The delimiting wall 5 of the flow chamber 10 is formed by the inner surface of a hollow body, wherein the cavity of the hollow body forms the flow chamber 10. The delimiting wall 5 is connected to the outer surface, which determines the external appearance of the fluidic component, of the hollow body. In
Depending on the position of the axes of rotation Ra, Rb, which in turn is dependent on the shape of the inner blocks 11a, 11b, on the shape or the presence of separators and on the fluid characteristics (type of the fluid, entry pressure and volume flow), the emerging fluid jet may exhibit an intense and/or abrupt change in acceleration or a virtually invariant profile with respect to time without abrupt changes in acceleration. Thus, the fluid distribution can be varied to a minimal extent within the spray fan within the oscillation angle.
For certain applications, a jet with edge emphasis is desirable, that is to say an oscillating jet which, averaged over time, remains for longer in the outer region than in the inner region of the spray fan. To generate such a jet, the position of the axes of rotation Ra, Rb, the shape of the inner blocks 11, the shape of the separators 105a, 105b (if present), the type of the fluid, the entry pressure and the volume flow may be selected such that, averaged over time, the fluid flow is in contact with the outlet channel 107 (with those portions 51a, 51b of the delimiting wall 5 which are oriented perpendicular to the oscillation plane and which are part of the outlet channel 107) for as long as possible. To generate a jet with edge emphasis, it is furthermore possible for the angle ε of the outlet widening 108 (if present) to be set to be smaller than the free oscillation angle of the fluid flow without the outlet widening 108.
The embodiment from
The rotation of the movable portions 51a, 51b causes the angle δ and also the width bEX of the outlet opening 102 to change. In this way, the oscillation angle of the emerging fluid flow, the jet impetus and the pressure loss of the component can be varied. By means of a reduction of the width bEX of the outlet opening 102, the jet impetus can be increased (in the case of an invariant internal pressure), and thus the cleaning performance can be increased as a result of the focusing of the jet force.
In a further embodiment, the axes of rotation Ra, Rb may be positioned even closer to the outlet opening 102, in order to thus minimize the coupling between the change in the angle δ and in the outlet width bEX, or prevent a change in the outlet width bEX.
In the embodiment from
By means of the displacement of the movable portions 51a, 51b, the spray characteristic, such as for example the oscillation angle, of the fluid flow can be changed. In this way, firstly, the spray angle α is varied. If the width bEX of the outlet opening 102 is increased, the oscillation angle is also increased, and the spray impetus (in the case of an invariant throughflow) is reduced. This is advantageous for example for cleaning or wetting of (sensitive) surfaces.
Through variation of the width bEX of the outlet opening 102, the nozzle size can be changed, that is to say, in the case of a constant entry pressure of the fluid, the throughflow can be regulated.
As an alternative to the movement of the movable portions 51a, 51b as per
The embodiment from
Alternatively, the two movable portions 51a, 51b may also be moved simultaneously in the same way (direction, speed). This may be realized for example by means of a telescopic construction of the fluidic component 1. Here, it is for example the case that the movable portions 51a, 51b are displaced along the longitudinal axis A relative to the rest of the fluidic component 1 by means of rails.
Irrespective of the specific movement of the movable portions 51a, 51b (or of other movable elements), the material of the movable portions 51a, 51b (or of the other movable elements) may comprise a harder or more wear-resistant material than the rest of the delimiting wall 5. It would thus be possible for the fluidic component 1 to be manufactured from a rust-resistant steel, and for the movable portions 51a, 51b (or the other movable elements) to be manufactured from a ceramic material.
In
In
The embodiment from
Alternatively, the inner blocks 11a, 11b may not be rotated about an axis of rotation but rather displaced in the oscillation plane in order to change the shape of the flow chamber 10. By means of a displacement along the longitudinal axis A, the cross-sectional areas of the entrances 104a1, 104b1 and exits 104a2, 104b2 of the secondary flow channels can be varied. By means of a displacement transversely with respect to the longitudinal axis A, the width of the main flow channel 103 and of the secondary flow channels 104a, 104b (in the second portion) can be varied.
Here, the surface 110a to be deformed may for example comprise a spring material which can assume two stable or metastable states and can be moved back and forth between these two states by means of the action of an external force (imparted by a device) or by means of a so-called internal force. The so-called internal force may result from the pressure of the fluid flow flowing in the fluidic component.
In the case of the fluidic component being used in the field of agricultural technology, the material of the surface 110a that is to be deformed may be selected (with regard to material thickness and elasticity) such that it deforms if the pressure at the inlet opening changes by at least 0.01 bar. If the fluidic component is used in the cleaning sector, the material of the surface 110a that is to be deformed may be selected (with regard to material thickness and elasticity) such that it deforms if a pressure change, in the case of which it is the intention for the flow characteristic in the flow chamber 10 to change, of 5 bar (for low-pressure cleaning) or of 10 bar (for high-pressure cleaning) occurs at the inlet opening. These pressure specifications may also serve for the selection of a suitable material for the deformable portions, mentioned further above, of the parts 51a, 51b. Instead of the spring material, use may also be made of a so-called intelligent material, such as for example a shape memory alloy. The deformation of the inwardly pointing surface 110a of the inner block 11a may be predetermined by means of additional joints or pivot points 110a1 and fixed points 110a2. In a further alternative, the wall thickness of the inwardly pointing surface 110a of the inner block 11a may, in certain portions, be formed with varying thickness, such that the deformability (flexibility) of the material is varied in targeted fashion in certain portions, and the surface 110a can then be correspondingly deformed under the action of an external force. Preferably, the inwardly pointing surface 110a of the inner block 11a is, in one stable or metastable state, shaped such that the main flow channel 103 steadily widens or diverges in the downstream direction. In the other stable or metastable state, the inwardly pointing surface 110a of the inner block 11a is preferably shaped such that, in the downstream direction, the main flow channel 103 initially diverges (widens) and, at the level of the final third of the inner block 11a, converges (narrows) along the longitudinal axis A. (It is basically also possible for other shapes to be assumed in the stable or metastable states.) By means of the change, effected in this way, of the shape of the main flow channel 103, the change in acceleration of the fluid flow in the profile with respect to time is reduced, or the change in acceleration assumes an approximately sinusoidal course. It is particularly advantageous if the inwardly pointing surface 110a is formed by a planar surface or a curved surface with a large radius of curvature. The inwardly pointing surface 110a may also comprise polygons or splines in order to thus for the most part form a virtually constant angle γ between the inner blocks 11a, 11b. In this way, it is possible for wedges to be formed on the inwardly pointing surface 110a which project into the main flow channel 103.
In a further embodiment, the inner block 11a, 11b is constructed such that the fin-ray effect can be utilized. With this effect, by means of a displacement or an action of force at one point, a defined curvature of the inner delimiting wall 110a, 110b of the main flow channel 103 can be realized. By means of a skeleton-like construction of the inner block 11a, 11b which is suitable for the fin-ray effect, it is possible for the weight of the fluidic component to be reduced owing to the additional cavities within the inner block 11a, 11b. This fin-ray effect can also be used for the targeted variation of the size of the cross-sectional area of the outlet opening, for example through variation of the shape of the portions 51a, 51b.
The inner block 11b illustrated on the right in
Through the variation of the shape of the inner blocks 11a, 11b as described with regard to
In
As an alternative to the deformable portions, the cross-sectional area of the secondary flow channels 104a, 104b may also be varied by means of a slide which can be moved into the secondary flow channels 104a, 104b transversely with respect to the flow direction in the secondary flow channels 104a, 104b.
In this embodiment, in the case of compressible fluids, it is substantially possible for the oscillation frequency to be varied. (In the case of an excessive reduction of the cross-sectional area of the secondary flow channels 104a, 104b, the oscillation may however be rendered inactive.) In this way, a fan jet can be generated which extends orthogonally with respect to the original oscillation plane.
In
Aside from the delimiting wall 5, the inner blocks 11a, 11b are also of telescopic or bellows-like design in order to adapt the length l11, l11′ of the inner blocks 11a, 11b in accordance with the component length l, l′ of the fluidic component 1. The change in the length l of the fluidic component 1 and in the length of the inner blocks 11a, 11b may be realized here in a mutually independent or coupled manner. In a further embodiment, it is possible for either only the length l11, l11′ of the inner blocks 11a, 11b or the component length l, l′ of the fluidic component 1 to be varied.
By means of the embodiment illustrated in
In a further embodiment, in the event of a change in the length of the inner blocks 11a, 11b, the orientation of the inwardly pointing surfaces 110a, 110b of the inner blocks 11a, 11b can also change, such that the angle γ simultaneously jointly changes. The change in the oscillation angle can thus be amplified. This is the case for example if the length l11 of the inner blocks 11a, 11b is changed but the distance between the inner blocks 11a, 11b (in the oscillation plane and transversely with respect to the longitudinal axis A) remains unchanged.
Depending on the arrangement of the channels 113a, 113b, the oscillation frequency of the fluid flow and the jet profile with respect to time of the emerging fluid jet can be changed.
The embodiment from
Downstream of the outlet opening 102, there may additionally be provided an outlet widening 108. This is illustrated by way of example in the embodiments from
In the embodiment of
In the embodiment of
Illustrated in the region of the entrance 104b1 of the secondary flow channel 104b are multiple (in this case, by way of example, three) elements 200′ around which flow can pass, which in the oscillation plane have an (in this case exemplary) circular cross section and which are displaceable in the oscillation plane. A device provided for the displacement of the elements 200′ is not illustrated in
Illustrated in the region of the exit 104b2 of the secondary flow channel 104b is a translationally adjustable element 200″ which is of (in this case exemplary) sickle-shaped form in the oscillation plane. The element 200″ is fastened to a device 201 which serves for changing the position and/or the orientation of the element 200″. By means of the position of the adjustable element 200″, the flow in the main flow channel can be additionally influenced, and the spray characteristic of the emerging fluid flow thus set in targeted fashion. Here, the further the element 200″ projects into the main flow channel 103, the smaller the oscillation angle of the emerging fluid flow can become.
The elements 200, 200′, 200″ illustrated in
In all embodiments in which a rotation about an axis of rotation is provided, it is possible for an eccentric to be used instead of the axis of rotation. It is thus possible for the relationship between an angle variation (for example of the angle δ or of the angle γ) and a change in distance (for example of the outlet width bEX or between those ends of the inner blocks 11a, 11b which face toward the inlet opening) to be reduced, or for the angle to be changed without simultaneously changing the distance.
In all embodiments in which multiple parts can be moved, the movement of said parts may take place in a coupled manner or independently of one another and simultaneously or in a time-offset manner. The speed with which the movement takes place may also be configured to be equal or different for the multiple parts.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2017 212 747.3 | Jul 2017 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2018/069785 | 7/20/2018 | WO | 00 |
