EP3658266B1 - Mixer with compensation channel and/or accumulation chamber - Google Patents

Description

The present invention relates to a mixer with a mixer housing that encloses a mixing space, an input part that can be connected to the mixer housing and that has at least two input openings for the components to be mixed, and a mixing element that extends at least in sections into the mixing space, with each of the input openings is in flow communication with the mixing chamber via at least one inlet channel.

Generic static and dynamic mixers are used, for example, in the dental field or for construction materials and adhesives. The mixing element of the mixer is used for the homogeneous mixing of several, usually two, viscous or pasty components, which are stored separately in a cartridge or a similar container so that they can be discharged. Typical consistencies/viscosities for dental impression materials are described in the DIN EN ISO 4823 standard. The mixing process often starts a reaction between the individual components, with the actual substance to be processed, for example a dental material or a building material or adhesive, being formed. Depending on the composition of the components and the area of application, they are mixed in different ratios. Typical mixing ratios include 1:10, 1:5, 1:4, 1:2 and 1:1.

Since the compositions and concentrations of the viscous/pasty components (hereinafter also referred to as simply: components) and their mixing ratio are coordinated with one another, it is crucial that the ratio of the components to one another is maintained not only during the filling process into the cartridge, but also during the mixing process itself .

For technical reasons, the filling of the components into the cartridges is associated with certain filling level fluctuations, typically in the range of 5%, with greater technical effort also 1%, of the filled volume. In addition, the arrangement of the respective dispensing pistons is associated with certain tolerances. As a result, one of the pistons is located further forward in the discharge direction. Both the technical fluctuations in the filling height and the slightly different arrangement of the dispensing pistons mean that one of the components enters the mixing chamber before the other component. Furthermore, the breakaway torque of the dispensing piston, i.e. the initial impulse of the dispensing piston when releasing from the storage position in the dispensing direction, can vary, in particular due to manufacturing fluctuations, so that even for perfect filling, one of the components will enter the mixing chamber before the other component. Since the components to be mixed generally have a different composition, the components also differ in their rheology and thus in their application behavior. Since the different composition inherently underlies a multi-component system, it is therefore not possible, even by optimizing the known constructions and the filling process, to rule out that even with 1:1 cartridges, one of the components enters the mixing chamber before the other component.

In other words, it will inevitably be observed that one component forms a so-called pre-flow, which enters the mixing space before the other component, so that at least the initial ratio of the components to one another deviates from the ideal mixing ratio. Such a forerun often leads to it being discharged from the mixer unmixed. The unmixed leading component must be discarded since it does not have the properties of the processing stock.

Although the filling-related fluctuations and irregularities in piston positioning occur with all viscous or pasty components, these are often tolerated, especially with large-volume and inexpensive components, e.g. sealing materials or adhesives. However, these fluctuations are unacceptable for small-volume and high-priced components, for example dental materials, since a larger proportion of the expensive material has to be discarded.

In addition, discarding the forerun is inconvenient for a user and creates a safety hazard in use because the forerun does not have the adhesive, impact and/or strength properties obtained for the blend. Also from a visual point of view, unintentional use of the pre-run can lead to undesired results.

EP 2 599 540 B1 describes a mixing element for a static mixer that reduces the overflow of a component by introducing that component through an inlet port separate from the other component to the mixing element. By guiding the components separately, a previously known lead can be compensated.

EP 2 527 029 A2 discloses a mixer having a star-like baffle plate having a central pin or spike extending upstream into the flow of material and diverging in the direction of flow into an axis-perpendicular plate.

The WO 2012 116 873 A1 also relates to the compensation of a lead. For this purpose, two deceleration chambers and a deflection element are provided, with the deflection element deflecting the component flows radially inwards.

Furthermore, describe the EP 0 664 153 A1 , the EP 0 584 428 A1 , the DE 29 902 666 U1 and the DE 3 606 001 A1 generic static mixers, which relate to the problems described above.

US 2012/0 199 607 A1 discloses a dispensing device with a two-component cartridge and a mixer that can be attached to it. The mixer should be able to be easily brought to and removed from the cartridge.

DE 36 06 001 A1 describes a metering and mixing gun for multi-component plastics. Each component is routed into the static mixing chamber via a supply duct provided with a throttle device.

In the documents WO 2013 0 26 722 A1 , EP 1 943 012 B1 , DE 10 112 904 A1 , DE 10 2004 008 748 A1 , DE 299 02 666 U1 , EP 2 190 563 B1 , EP 1 458 467 B1 and EP 1 892 033 A1 describes dynamic mixers which are intended to compensate for a lead.

From the EP 0 885 651 B1 a mixer is known with a foreshots-collecting combining chamber provided within a mixer inlet area. The component inlet openings are divided by a separating rib and the path of the excess component is extended.

The WO 2012/116863 A1 and the DE 20 2012 013429 U1 each describe a mixer with a mixer housing that encloses a mixing chamber, an inlet part that can be connected to the mixer housing and has at least two inlet openings for the components to be mixed, and a mixing element that extends at least in sections into the mixing chamber extends, wherein each of the inlet openings is in flow communication with the mixing chamber via an inlet channel.

In the DE 20 2012 013429 U1 a flowable reservoir chamber is also provided, which receives a flow. The WO 2012/116863 A1 discloses a channel which accommodates the mixing components, however, the components are already mixed in this with the aid of arms, and thus any forerun is not only accommodated but also used during mixing. This can falsify the mixing ratio.

For the solutions described above, the fact is essentially exploited that a bottling-related fluctuation of a component that is present in excess has a greater effect than with a component that is present in deficit. Therefore, there is only a lead of the component present in excess, while a bottling-related fluctuation in the component present in deficit does not form a lead. Especially at If there is a large excess of one component, e.g. with the usual 1:10 mixing ratio, the component present in excess also occurs in advance because the container holding this component and the associated dispensing piston are significantly larger than the respective components of the component present in deficit. In other words, with the known solutions it is essential to know before filling the components which component is in excess and will therefore form forerun. Therefore, the known solutions can only be used with unequal mixing ratios.

However, with mixing ratios of 1:1 and sometimes already with similar mixing ratios with small volume differences, e.g. 1:1.25 or 1:2, it is not possible to predict with certainty which of the components is present in too high a proportion and will therefore form a lead . This problem occurs in all known multi-component cartridges, particularly regardless of whether a static or dynamic mixer is used.

It is therefore the object of the present invention to provide a mixer which, for any mixing ratio, in particular with small volume differences, such as 1:1 to 1:2, takes up the forerun, which in particular is formed both from the first component and from the second component can.

This object is achieved with a mixer according to claim 1.

According to the invention, the mixer has a mixer housing with a mixing chamber, an inlet part that can be connected to the mixer housing and has at least two inlet openings for the components to be mixed, and a mixing element, the mixing element extending at least in sections into the mixing chamber. Each of the entrance openings is standing in flow communication with the mixing chamber via at least one inlet channel. In addition, it is provided that at least one compensation channel is formed in the inlet part, which connects the inlet openings to one another. In addition or as an alternative to this, at least one storage chamber for receiving the flow is provided in the mixing element.

By connecting the inlet openings to a compensation channel, flow emerging from the inlet openings can enter the compensation channel and be collected there as flow. Because the inlet ports are interconnected, forerun is collected independently of the component making up the forerun. In other words, the connection between the inlet openings ensures that the components reach the compensation channel through these inlet openings without having to make a preselection with regard to the components forming the flow.

The compensation channel allows for self-regulation with regard to the flow, since the compensation channel is first filled by the preceding component until the further component flows into the compensation channel and further filling of the compensation channel by the preceding component is prevented. Both can then enter the mixing chamber separately or together via the inlet channels.

In other words, the invention can be seen in the fact that a radially open compensation channel is provided. The compensation channel is formed by an outer closed ring and by an inner ring with symmetrically arranged openings.

During discharge, the leading component spreads out in the compensation channel until it is countered by the trailing component. Depending on the pre-travel, a variable component front is created. The Components form a contact surface on this front. After the compensation channel is filled, the component front remains in its position in the compensation channel, which means that the component mass that continues to flow in flows the shortest way out of the inlet openings through the corresponding openings in the inlet to the mixing chamber and then axially in the discharge direction.

The arrangement of at least one storage chamber in the mixing element also allows the intake of the feed regardless of which of the components forms the feed, since the storage chamber or the storage space is provided in the mixing element and is therefore filled by the preceding component. The storage chamber according to the invention is designed in such a way that the flow is received and remains in the storage chamber. The storage chamber is preferably arranged in the first third of the mixing space in the direction of flow of the components.

The storage chamber is designed in such a way that it has closed side walls and only one opening, which is formed as an inlet opening in a transverse wall. Since the storage chamber has only one inlet opening but is otherwise not flow-connected to the other chambers, the flow entering the storage chamber is held there so that it essentially no longer participates in the further mixing process.

The mixer according to the invention can be a static or a dynamic mixer.

In particular, it is according to the invention that the compensation channel is provided in the input part. Therefore, the compensation channel can be implemented with any type of mixer and works independently of the concrete design of the mixer.

In a preferred variant, the internal volume of the compensation channel and/or the storage chamber is adapted to the filling-related fluctuations in such a way that the fluctuations in the volume of the components are smaller than the internal volume of the compensation channel and/or the storage chamber. In other words, the internal volume of the compensation channel and/or the storage chamber corresponds to 1% to 10%, in particular 1% to 8%, particularly preferably 1% to 5%, of the volume of a component when the mixing ratio is 1:1. If the mixing ratio deviates from 1:1, the volume of the component present in larger proportions is decisive.

Alternatively or additionally, the internal volume of the compensation channel and/or the storage chamber corresponds to 1% to 10%, in particular 1% to 8%, particularly preferably 1% to 5%, of the volume of the component present in excess relative to the volume of the component present in deficit Component or the volume of the component present in excess based on the volume of the component present in excess.

In a preferred embodiment, two compensation channels are formed in the input part, each of which connects the input openings to one another. This prevents any blockage of the flow connection from the inlet opening to the mixing space.

In a further embodiment, the inlet channels are designed in such a way that the components to be mixed are fed into the mixing chamber separately from one another. This prevents the components from reacting prematurely and preventing the intake ports from becoming clogged. In addition, the separate feeding of the components into the mixing space allows better mixing of the components with one another.

It is further preferred if the two inlet openings are arranged diametrically opposite one another in the inlet part, the inlet channels extending along a diagonal connecting the inlet openings and being separated from one another by a partition running transversely to the diagonal. The partition wall prevents any mixing of the components at the inlet openings, which could cause them to become clogged. Preferably, the partitions are formed along part of the periphery of an entry port.

If the entire circumference of the inlet opening is available for the components to flow into the at least one compensation channel, it is preferred if the partition walls are in particular along less than 50%, preferably less than 40%, very particularly preferably between 20% and 30% of the entire circumference of the corresponding Input opening are arranged.

If the entire circumference of the inlet opening is not available for the inflow of the components, e.g. because the inflow of the components through the inlet openings at the radial edge of the inlet is partially blocked, then it is preferable if the partitions along less than 80%, preferably less than 70%, very particularly preferably between 40% and 60% of the circumference of the corresponding inlet opening available for inflow are arranged.

According to a further preferred embodiment, the inlet ducts are designed in such a way that the components to be mixed are guided into the mixing chamber, at least partially enveloping one another. This supports the subsequent mixing process in the mixing room.

As an alternative to this, the inlet channels can be in flow connection with one another, so that the components to be mixed are guided together into the mixing space.

In a preferred variant, the at least one compensation channel extends essentially in the shape of a circular arc between the inlet openings. Such an arrangement ensures that the components can flow into the compensation channel from each of the inlet openings.

In a further embodiment, the at least one compensation channel runs radially outside of the inlet channels. As a result, the flow is routed outwards from the inlet openings or inlet channels into the compensation channel, which is particularly preferred when the inlet into the mixing chamber is arranged centrally, viewed radially. As a result, the flow initially fills the external compensation channel and the components can then enter the mixing chamber together. This prevents the inlet channels from being interrupted by the compensation channel and also ensures a relatively short path from the inlet openings into the mixing chamber, since this path leads centrally along the inlet channels into the mixing chamber. This also reduces the discharge pressure, since the components have to be discharged over a short distance with less effort.

Furthermore, it is preferred if the at least one compensation channel and the inlet channels are designed as depressions or grooves in the inlet part, which are closed at least in regions by the mixer housing or the mixing element. Since the inlet part is manufactured separately from the mixer housing, further material can be saved during manufacture in this variant. It is particularly preferred if the mixer housing or the mixing element covers the compensation channel by a disk-shaped or funnel-shaped collar in the inlet area of the mixing space.

The compensation channel has a mirror plane running through the centers of the input openings. In addition or as an alternative to this, the compensation channel can have a multiple rotating mirror axis. In a preferred variant, the number of rotation axes corresponds to the number of inlet openings. So if there are two input ports, a two-fold rotating mirror axis is preferred, if there are three input openings, a three-fold rotating mirror axis is preferred, etc. This symmetry ensures that with mixing ratios of 1:2 to 1:1 or 1:1:2 to 1: 1:1 compensation of the lead is ensured for more than two components, regardless of the respective leading component.

Finally, it is preferred that the inlet part and the mixer housing are designed and adapted to one another in such a way that the components to be mixed, which emerge from the inlet openings and are to be mixed, flow through 90° from a flow direction extending parallel to the longitudinal axis of the mixer housing into a flow direction transverse to the longitudinal axis of the Mixer housing are deflected. The deflection prevents the components from penetrating directly into the mixing chamber past the compensation channel.

A flow wall is provided along the circumference of at least one inlet opening and is concave or convex in shape when viewed from the corresponding inlet opening.

Particularly in the event that the entire circumference of the inlet opening is available for the components to flow into the at least one compensation channel, it is preferred if the flow wall, in particular is arranged along less than 50%, preferably less than 40%, most preferably between 20% and 30% of the total perimeter of the corresponding entrance opening.

If the entire circumference of the inlet opening is not available for the inflow of the components, e.g. because the inflow of the components through the inlet openings at the radial edge of the inlet is partially blocked, then it is preferred if the flow wall along less than 80%, preferably less than 70%, most preferably between 40% and 60% of the circumference of the corresponding inlet opening available for inflow.

In a continuation of this idea, it is preferred that the at least one flow wall closes off in a sealing manner with a disk-shaped or funnel-shaped collar of the mixer housing or of the mixing element. In other words, the axial length of the flow wall corresponds to the axial length of the compensation channel.

If several flow walls are provided, it is preferable to arrange them at a distance from one another, so that the components can flow centrally through the gaps formed between the flow walls in the direction of the mixing element. The extent of the distance between two adjacent flow walls defines the pressure drop in the center toward the mixing element. The distance is preferably selected in such a way that the pressure drop between the walls is greater than the pressure drop in the compensation channel, so that the material flowing ahead flows into the compensation channel before it enters the mixing chamber centrally.

It is preferred if the inlet part has a storage space that runs radially outside the compensation channel and/or the inlet channels. The Storage space is closed off in the material discharge direction of the components, so that the components cannot flow from the storage space into the mixing element. This separates the storage space from the intake ports. A storage space is particularly advantageous if a large-volume flow is to be expected. Storage space is therefore advantageous, in particular for mixing ratios that deviate from 1:1, in particular 1:10.

Furthermore, it is preferred if at least one of the inlet openings is assigned an optional deflection plate and/or a flow clamp, which at least partially covers and/or laterally delimits the corresponding inlet opening. The deflection plate is preferably provided above the corresponding inlet opening and is therefore located directly in the material discharge direction, so that the component flowing through the corresponding inlet opening hits the deflection plate when exiting the inlet opening and is deflected, in particular in the direction of the mixing chamber. The flow clip preferably delimits the corresponding inlet opening laterally in such a way that the component which flows through the corresponding inlet opening is directed in the direction of the mixing space when it exits the inlet opening. Both the deflection plate and the flow clamp therefore allow a flow direction to be specified for the component flowing out of the corresponding inlet opening. This is particularly advantageous when the proportion of the corresponding component is low, so that this component can flow almost completely into the mixing space and any residues in the input part are minimized. The advantages of the deflection plate described above can also be achieved by a collar provided on the mixing element if this, comparable to the deflection plate, covers at least one of the inlet openings when the inlet part and the mixing element are mounted in the mixer.

It is also preferred if the mixing element has a flow chamber adjacent to the storage chamber, which is in flow communication with the mixing space via a through-opening.

In a further development of this idea, it can be provided that the flow chamber is delimited by a transverse wall in the material discharge direction and that the transverse wall comprises a transverse wall opening, so that the components can at least partially flow through the transverse wall opening. This reduces the discharge pressure when discharging the components through the mixer, resulting in greater ease of use when discharging.

It is also preferred if the cross section of the mixing element perpendicular to the material discharge direction in the section of the storage chamber and/or flow chamber is 105% to 150%, preferably 105% to 120%, particularly preferably 110% ± 5% of the cross section perpendicular to the material discharge direction Mixing element viewed in material discharge direction is subsequent section of the mixing element. In other words, the mixing element is enlarged in an area of the storage chamber and/or flow chamber. As a result, a higher flow cross section can be achieved in this area with the stability of the mixing element remaining the same, which is advantageous for reducing the discharge pressures, particularly in the case of highly viscous components. Furthermore, the capacity of the storage chamber is improved, so that a large-volume flow can be accommodated.

The storage chamber and/or flow chamber are preferably provided in the section that overlaps with the inlet section of the mixing sleeve, which has the advantage that a widening of the mixing element can be accommodated in this section by appropriately adapting the inner contour of the inlet section of the mixing sleeve. Otherwise can Of course, the mixing sleeve itself can be adjusted accordingly to the widened contour of the mixing element.

The invention is explained in more detail below using exemplary embodiments and with reference to the drawings. All of the features described and/or illustrated form the subject matter of the invention, either alone or in any combination, regardless of how they are summarized in the claims or their dependencies.

Fig. 1a bis 1d

eine erste Seitenansicht (Fig. 1a), eine zweite Seitenansicht (Fig. 1b), eine Draufsicht (Fig. 1c) und eine Perspektivansicht (Fig. 1d) eines ersten Eingangsteils,

Fig. 2a bis 2e

mehrere Draufsichten (Fig. 2a bis 2c) des ersten Eingangsteils mit Illustration der Strömungsrichtungen der Komponenten,

Fig. 3a und 3b

eine Perspektivansicht (Fig. 3a) und eine Draufsicht (Fig. 3b) eines zweiten Eingangsteils,

Fig. 4a bis 4e

eine Draufsicht (Fig. 4a), eine Perspektivansicht (Fig. 4b) und weitere Draufsichten (Fig. 4c bis 4e) eines dritten Eingangsteils,

Fig. 5a und 5b

eine Draufsicht (Fig. 5a) und eine Perspektivansicht (Fig. 5b) eines vierten Eingangsteils,

Fig. 6a bis 6c

eine Draufsicht (Fig. 6a), eine Perspektivansicht (Fig. 6b) und eine Draufsicht (Fig. 6c) eines fünften Eingangsteils,

Fig. 7a bis 7e

eine Draufsicht (Fig. 7a), eine Perspektivansicht (Fig. 7b) und weitere Draufsichten (Fig. 7c bis 7e) eines sechsten Eingangsteils,

Fig. 8a bis 8c

eine Perspektivansicht (Fig. 8a), eine Seitenansicht (Fig. 8b) und eine Detailansicht B (Fig. 8c) eines ersten Mischelements,

Fig. 9a und 9b

eine Perspektivansicht (Fig. 9a) eines Helixmischers und eine Draufsicht des entsprechenden Mischeranschlusses (Fig. 9b) gemäß dem Stand der Technik,

Fig. 10

mehrere Draufsichten eines Eingangsteils und eines Mischers beim Austragen zweier Komponenten zu unterschiedlichen Zeitpunkten gemäß dem Stand der Technik,

Fig. 11

eine Explosionsansicht eines erfindungsgemäßen Mischers, mit Mischelement, Mischergehäuse und Eingangsteil,

Fig. 12a und 12b

eine erste Perspektivansicht (Fig. 12a) und eine zweite Perspektivansicht (Fig. 12b) eines zweiten Mischelements mit Eingangsteil,

Fig. 13a und 13b

eine erste Perspektivansicht (Fig. 13a) und eine Seitenansicht (Fig. 13b) des ersten Mischelements mit Eingangsteil gemäß der Fig. 12 und 12b,

Fig. 14

mehrere Draufsichten des zweiten Eingangsteils, des Mischers und die Komponenten 1 und 2 zu unterschiedlichen Zeitpunkten t1, t2 und t3,

Fig. 15

mehrere Draufsichten des dritten Eingangsteils mit (rechts oben) und ohne (links oben) Einlasskanal in den Mischraum (Mischereingang),

Fig. 16 a und 16b

eine Perspektivansicht (Fig. 16a) und eine Detailansicht (Fig. 16b) des ersten Mischelements mit Eingangsteil,

Fig. 17a bis 17c

eine Draufsicht (Fig. 17a), eine Perspektivansicht (Fig. 17b) und einen Längsschnitt (Fig. 17c) entlang der Schnittebene B-B eines siebten Eingangsteils,

Fig. 18a bis 18c

eine Draufsicht (Fig. 18a), eine Perspektivansicht (Fig. 18b) und einen Längsschnitt (Fig. 18c) entlang der Schnittebene E-E eines achten Eingangsteils,

Fig. 19a bis 19c

eine Perspektivansicht (Fig. 19a), eine Seitenansicht (Fig. 19b) und einen Längsschnitt (Fig. 19c) entlang der Schnittebene A-A eines dritten Mischelements,

Fig. 20a bis 20c

eine Perspektivansicht (Fig. 20a) und eine Seitenansicht (Fig. 20b) und einen Längsschnitt (Fig. 20c) entlang der Schnittebene B-B eines vierten Mischelements,

Fig. 21a bis 21c

eine Perspektivansicht (Fig. 21a) und eine Seitenansicht (Fig. 21b) und einen Längsschnitt (Fig. 21c) entlang der Schnittebene C-C eines fünften Mischelements,

Fig. 22a bis 22c

eine Perspektivansicht (Fig. 22a) und eine Seitenansicht (Fig. 22b) und einen Längsschnitt (Fig. 22c) entlang der Schnittebene D-D eines sechsten Mischelements,

Fig. 23a bis 23c

eine Perspektivansicht (Fig. 23a) und eine Seitenansicht (Fig. 23b) und einen Längsschnitt (Fig. 23c) entlang der Schnittebene E-E eines siebten Mischelements, und

Fig. 24a bis 24c

eine Perspektivansicht (Fig. 24a) und eine Seitenansicht (Fig. 24b) und einen Längsschnitt (Fig. 24c) entlang der Schnittebene F-F eines achten Mischelements.

They show schematically:

Figures 1a to 1d

a first side view ( Fig. 1a ), a second side view ( Fig. 1b ), a plan view ( 1c ) and a perspective view ( Fig. 1d ) of a first input part,

Figures 2a to 2e

multiple plan views ( Figures 2a to 2c ) of the first input part with illustration of the flow directions of the components,

Figures 3a and 3b

a perspective view ( Figure 3a ) and a top view ( Figure 3b ) of a second input part,

Figures 4a to 4e

a top view ( Figure 4a ), a perspective view ( Figure 4b ) and more plan views ( Figures 4c to 4e ) of a third input part,

Figures 5a and 5b

a top view ( Figure 5a ) and a perspective view ( Figure 5b ) of a fourth input part,

Figures 6a to 6c

a top view ( Figure 6a ), a perspective view ( Figure 6b ) and a top view ( Figure 6c ) of a fifth input part,

Figures 7a to 7e

a top view ( Figure 7a ), a perspective view ( Figure 7b ) and more plan views ( Figures 7c to 7e ) of a sixth input part,

Figures 8a to 8c

a perspective view ( Figure 8a ), a side view ( Figure 8b ) and a detail view B ( Figure 8c ) of a first mixing element,

Figures 9a and 9b

a perspective view ( Figure 9a ) of a helical mixer and a top view of the corresponding mixer port ( Figure 9b ) according to the state of the art,

10

several top views of an input part and a mixer when discharging two components at different times according to the prior art,

11

an exploded view of a mixer according to the invention, with mixing element, mixer housing and input part,

Figures 12a and 12b

a first perspective view ( 12a ) and a second perspective view ( Figure 12b ) a second mixing element with input part,

Figures 13a and 13b

a first perspective view ( 13a ) and a side view ( Figure 13b ) of the first mixing element with input part according to the Figures 12 and 12b ,

14

several top views of the second input part, the mixer and the components 1 and 2 at different times t1, t2 and t3,

15

several top views of the third input part with (top right) and without (top left) inlet channel into the mixing chamber (mixer inlet),

16a and 16b

a perspective view ( 16a ) and a detail view ( Figure 16b ) of the first mixing element with input part,

Figures 17a to 17c

a top view ( Figure 17a ), a perspective view ( Figure 17b ) and a longitudinal section ( Figure 17c ) along the cutting plane BB of a seventh input part,

Figures 18a to 18c

a top view ( 18a ), a perspective view ( Figure 18b ) and a longitudinal section ( 18c ) along the cutting plane EE of an eighth input part,

Figures 19a to 19c

a perspective view ( Figure 19a ), a side view ( Figure 19b ) and a longitudinal section ( Figure 19c ) along the cutting plane AA of a third mixing element,

Figures 20a to 20c

a perspective view ( Figure 20a ) and a side view ( Figure 20b ) and a longitudinal section ( Figure 20c ) along the cutting plane BB of a fourth mixing element,

Figures 21a to 21c

a perspective view ( Figure 21a ) and a side view ( Figure 21b ) and a longitudinal section ( Figure 21c ) along the cutting plane CC of a fifth mixing element,

Figures 22a to 22c

a perspective view ( 22a ) and a side view ( Figure 22b ) and a longitudinal section ( Figure 22c ) along the cutting plane DD of a sixth mixing element,

Figures 23a to 23c

a perspective view ( Figure 23a ) and a side view ( Figure 23b ) and a longitudinal section ( 23c ) along the cutting plane EE of a seventh mixing element, and

Figures 24a to 24c

a perspective view ( 24a ) and a side view ( Figure 24b ) and a longitudinal section ( Figure 24c ) along the cutting plane FF of an eighth mixing element.

The Figures 1a to 1d show a first embodiment of the input part 1 with input openings 2 for the components to be mixed. The first input part 1 has a guide projection 3 whose function in the WO 2013/026716 is explained and to which reference is made in this respect.

At least one compensation channel 4 is formed between the inlet openings 2 ( Figures 1c and 1d ), which connects the inlet openings 2 with each other. Flow entering through the inlet openings 2 is taken up by the compensation channel 4 . The inlet openings 2 are diametrically opposed to one another. Furthermore, at each of the inlet openings 2 there is provided a flow wall 5 which is formed along a part of the circumference of each inlet opening 2, respectively. Viewed from the respective inlet opening 2 on which the corresponding flow wall 5 is formed, the flow wall 5 is formed along the circumference and is therefore concave. In which case shown here, the components cannot flow into the compensation channel 4 over the entire circumference of the inlet openings 2, as can be seen from FIG 1c clearly results.

The functioning of the compensation channel 4 is based on the Figures 2a to 2c explained.

In the Figure 2a component B forms a lead. This exits through an opening and flows along the flow direction 6B past a flow wall 5 into the compensation channel 4. The flow of component B flows along the compensation channel 4 until component A along the flow direction 6A also enters the compensation channel 4 and the flow component B stops. Then both components A and B flow centrally through a further inlet opening into the mixing space (not shown).

in the in Figure 2b example shown, component A forms the flow, which flows along flow direction 6A into compensation channel 4 until component B also flows into compensation channel 4 .

in the in Figure 2c In the example shown, no component forms a lead, so that both components meet in the compensation channel 4 halfway through the flow path and then enter the mixing chamber (not shown) through an opening 7 illustrated centrally here. The inlet channel 7a connects the inlet openings 2 through the opening 7 with the mixing space (not shown).

The Figures 3a and 3b show in perspective view ( Figure 3a ) and in top view ( Figure 3b ) A modification of the first input part as a second embodiment, wherein between the input openings 2 at least one in the compensation channel 4 protruding indentation 8 is provided. In the case shown here, two opposing indentations 8 are provided, which direct the flow directions 6A and 6B of components A and B more towards the central opening 7 of the mixing space (not shown).

In the Figures 4a to 4e a third embodiment of the input part 1 is shown. In comparison to the first inlet part 1, two further flow walls, called deflection walls 9 here, are provided which, together with the flow walls 5, which are arranged at the inlet openings 2, form a circular structure 10. The flow walls 5 are designed convex from the respective inlet opening 2 in such a way that the center point of the circular structure 10 coincides with the center point of the inlet part 1 .

The Figure 4c shows the flow direction 6A and 6B in the case that none of the components forms a forerun, while in in the Figure 4d illustrated case, the component B forms a lead and in the Figure 4e component A forms a lead.

The flow walls 5 and the deflection walls 9 are arranged at a distance from one another, so that openings are formed between each deflection wall 9 and the adjacent flow walls 5, or between each flow wall 5 and the adjacent deflection walls 9. Components A and B can flow through the openings into the centrally arranged entrance to the mixing chamber (not shown). Due to the arrangement of the flow walls 5 and the deflection walls 9, the components A and B first fill the compensation channel 4 and then flow through at least one inlet channel 7a centrally into the mixing chamber.

In the Figures 5a and 5b a fourth embodiment of the input part 1 is shown, which is based on the first embodiment of the input part 1, but was supplemented by a partition 11. The partition wall 11 lies between the inlet openings 2 and below the central inlet area to the mixing chamber (not shown). Furthermore, two inlet channels of the components into the mixing chamber are separated from one another by the partition wall 11 .

The in the Figures 6a to 6c The fifth embodiment of an entry part 1 shown has an enveloping element 12 arranged centrally in the entry part 1 . A circumferential compensation channel 4 is provided radially around the enveloping element 12 and receives the flow of the components A and/or B.

The enveloping element 12 is essentially circular and has a central opening 12a, which opens in the direction of an inlet opening of a component and guides it centrally in the direction of the mixing space. A further opening is arranged opposite the central opening 12a in the direction of the other component, which guides it in a substantially semi-circular channel 12b around the central opening 12a. As a result, components A and B are introduced into the mixing chamber approximately coaxially with one another, which facilitates the subsequent mixing of the two components in the mixing chamber.

In the Figure 6c the flow directions 6A and 6B of the components A and B are shown. In the case shown here, no lead of components A and B is formed.

The Figures 7a to 7e show a sixth embodiment of the input part 1 with a further variant of an enclosing element 12 with flow walls 5. The flow walls 5 prevent components A and B from flowing directly into the enclosing element 12. This reduces the flow resistance increased to flow into the enveloping element 12, so that this embodiment is preferred for thin-viscous components.

In the Figures 8a to 8c a mixing element 13 with storage chambers 14 is shown, which are arranged in the entrance area of the mixing chamber and can absorb the flow that occurs. The storage chambers 14 are closed at their end in the direction of flow of the components, so that the flow does not enter the further mixing chamber and does not falsify the mixing ratio.

The mixing element 13 has a disk-shaped or funnel-shaped collar 15 on the inlet side, which is designed in such a way that it covers the inlet part 1 and partially or completely closes the compensation channel 4 .

For a better understanding of the effect of the invention is in the Figures 9a, 9b and 10 a helical mixer 16 with known mixer connection 17 and known input part 18 according to the prior art is shown. Figure 9b shows the first web 19 of the helical mixer and the inlet openings 2 through which the components flow into the inlet part 18 .

To illustrate the problem underlying the invention according to the prior art shows the figure 10 at different points in time t1, t2, t3, t4 and t5, which increase in this order, the components A and B and their interface in the input part 18. At point in time t1 it becomes clear that one component takes up significantly more volume in the input part 18 than the second component . The first component thus forms a lead and is present almost exclusively in input part 18 at point in time t2. Therefore in the in 10 Below shown top views of the mixer and through the mixer pipe at the time t3 practically exclusively the leading component present in the mixing element. The proportion of component A only decreases as the discharge continues (points in time t4 and t5).

figure 11 shows an exploded view of a mixer according to the invention with a mixing element according to FIG Figures 8a to 8c , a mixer housing 13a and an input part 1.

Figures 12a and 12b show another mixing element 13 with an input part 1. In FIG 12a It can be clearly seen that the disk-shaped or funnel-shaped collar 15 covers the compensation channel 4 in the inlet part 1 in the discharge direction of the components, so that the components from the inlet part 1 enter the mixing element 13 centrally through a central inlet opening 13b (see Fig. Fig. 13 a) stream.

The transition from input part 1 to the mixing element 13 is also from the Figures 13a and 13b clearly.

figure 14 shows several top views of the second input part 1 according to FIG Figures 3a and 3b , the mixer and the components A and B at different times t1, t2 and t3 which increase in this order. The advance of component A is compensated for by the compensation channel 4 according to the invention, so that both components A and B enter the mixing chamber almost simultaneously (bottom right).

In figure 15 a plan view of the third input part is shown above with (top right) and without (top left) inlet channel 7a into the mixing chamber (mixer inlet). In the middle of figure 15 the flow of component A is shown on the left (time t1) and on the right the position of components A and B shortly before they flow into the central inlet channel 7a (time t2) in the mixing chamber. As can be seen, the flow of component A is stopped by the inflow of component B, so that the present invention allows self-regulation with regard to the volume of the flow and also a Compensation achieved regardless of whether component A forms the lead (as shown) or component B (not shown). When entering the mixer (below in figure 15 ) (time t3) the components A and B are present in the intended mixing ratio of 1:1.

The Figures 16a and 16b illustrate the storage chambers 14 in the mixing element 13. As shown in particular in the detailed view ( Figure 16b ) to see, the storage chambers 14 lie on a line lying through the center point of the mixing element 13, or diametrically opposite.

The input parts 1 according to a seventh embodiment ( Figures 17a to 17c ) and an eighth embodiment ( Figures 18a to 18c ) are optimized for a mixing ratio of the components that deviates from 1:1. The mixing ratio is preferably 1:10.

In this case, a pre-run of the component present in a 10-fold excess is to be expected, since this has a correspondingly higher volume compared to the component present in the deficit, so that proportional fluctuations, for example during the filling process, and thus a pre-run to be compensated for, practically exclusively for the component present in excess become relevant.

The Figures 17a to 17c show a seventh input part 1, in which case the component present in excess can flow into the input part 1 through the input opening 2a, while the component present in excess can flow into the input part 1 through the input opening 2b.

The design of the compensation channels 4, the flow walls 5 and the deflection walls 9 of the seventh input part 1 is comparable to that in FIGS Figures 4a to 4e shown third input part 1, so that reference is made to the corresponding statements above.

Furthermore, the seventh input part 1 comprises a deflection plate 20 located in the material discharge direction, which at least partially covers the input opening 2a in its radially outer area in such a way that the component flowing in through the input opening 2a is deflected in the direction of the central opening to the mixing chamber 7 (not shown). ( Figure 17c ). This prevents the component present in the deficit and flowing in through the inlet opening 2a from flowing into an area of the inlet part 1 through which one of the components no longer flows in the further course of the discharge and therefore no longer reaches the mixing chamber. As a result, the deflection plate 20 prevents a loss of the component present in the deficiency in the area of the input part 1. As described above, the advantages associated with the deflection plate 20 can also be achieved by the collar 15 of the mixing element 13.

In the Figures 18a to 18c an eighth embodiment of the input part 1 is shown. The flow wall 5 is connected here continuously and centrally to a web 19 which lies along a connecting axis between the inlet openings 2a and 2b. The inlet opening 2a is bordered by a flow direction indicator 22, so that the inlet channel 7a points in the direction of the central opening to the mixing chamber 7 (not shown). The compensation channel 4 is provided radially on the outside and can accommodate the flow. This embodiment has a high inner prelumen of the compensation channel 4, so that this embodiment is particularly suitable for large-volume pre-runs.

The Figures 19a to 24c show further embodiments of a mixing element 13 with a storage chamber 14. The components to be mixed can flow in through the inlet opening 13b provided centrally in the collar 15 from the inlet part 1 (not shown).

Figures 19a to 19c show a mixing element 13 according to a third embodiment. From the longitudinal view of Figure 19b the arrangement of the storage chamber 14 in the first part of the mixing element 13, viewed in the material discharge direction, can be seen. In addition, the section plane AA is shown, while the corresponding longitudinal section in the Figure 19c is shown.

When the components flow in through the inlet opening 13b, they are divided at a central wall 23 and flow partly into a storage chamber 14 and partly into a flow chamber 24. From the flow chamber 24, the components flow through a passage opening 25 to the chambers of the mixing element 13, the length of which is in Material discharge direction is defined by the transverse walls 26.

In the third embodiment shown here, the cross section of the passage opening 25 is smaller than the cross section of the flow chamber 24. The smaller cross section is decisive for the pressure drop when the components are discharged, in this case the cross section of the passage opening 25. This can result in relatively high discharge pressures , The discharge pressure also being influenced by the specific design of the mixing element 13 and the specific viscosity of the components.

In the Figures 20a to 20c a fourth mixing element 13 is shown in a perspective view, a side view and as a longitudinal section along the section plane BB. Compared to that in the Figures 20a to 20c In the example shown, the mixing element 13 was shortened at its end lying in the material discharge direction. This reduces the discharge pressure, making this embodiment suitable for higher viscosity components.

The Figures 21a to 21c show a mixing element 13 in a fifth embodiment. Compared to the third embodiment according to Figures 20a to 20c the draft angles on open sides of the mixing element were increased here. The draft angles have in particular an angular range of 0.1° to 2°, preferably 0.1° to 1° and particularly preferably 0.5°±0.1°.

In the Figures 22a to 22c a sixth mixing element is shown that has been widened in the area of the storage chamber 14 and the flow chamber 24 . This reduces the pressure when the components are discharged, since the flow cross-section is increased overall in this area. This embodiment is therefore particularly advantageous for highly viscous components.

A seventh mixing element 13 is in the Figures 23a to 23c shown. In comparison to the previous embodiments, the storage chamber 14 is reduced here in such a way that the passage opening 25 has been enlarged. Here the flow cross section of the flow chamber 24 and the passage opening 25 is the same size. This in turn results in the discharge pressure being reduced compared to other embodiments. However, since the storage chamber 14 has been reduced in size, this embodiment is particularly suitable in combination with an inlet part 1 which has a relatively large compensation channel 4 or a storage space 21 .

The Figures 24a to 24c show an eighth mixing element. Here, a transverse wall opening 27 was added in a transverse wall closing off the flow chamber 24 in the material discharge direction. This allows some of the components to flow through the transverse wall opening 27 directly into the adjoining mixing space without having to pass through the through-opening 25 . This reduces the discharge pressure of the components, as part of these does not have to change its direction of flow in order to flow through the passage opening 25 .

Reference List

1

input part

2, 2a, 2b

entrance openings

3

Leadership Advantage

4

compensation channel

5

flow wall

6A

Flow direction of a component A

6B

Flow direction of a component B

7

Opening to the mixing room

7a

inlet channel

8th

indentation

9

baffle

10

circular structure

11

partition wall

12

enclosing element

12a

central opening

12b

semicircular canal

13

mixing element

13a

mixer body

13b

intake port

14

storage chamber

15

disc or funnel shaped collar

16

helix mixer

17

mixer connection

18

known entrance

19

web

20

baffle plate

21

storage space

22

flow director

23

center wall

24

flow chamber

25

passage opening

26

bulkhead

27

bulkhead opening

Claims (17)

1. A mixer with a mixer housing (13a), which encloses a mixing space, an input part (1) that can be connected with the mixer housing (13a) and has at least two input openings (2, 2a, 2b) for the components (A, B) to be mixed, and a mixing element (13) that at least sectionally extends into the mixing space, wherein each of the input openings (2, 2a, 2b) is flow connected with the mixing space via at least one inlet channel (7a), characterized in that at least one radially open compensation channel (4) is additionally formed in the input part (1), which connects the input openings (2, 2a, 2b) with each other, and is formed by an outer closed ring and by an inner ring with symmetrically arranged perforations, wherein the compensation channel (4) has a mirror plane that runs through the center points of the input openings (2, 2a, 2b), and wherein a flow wall (5) with a concave or convex shape is provided along the periphery of the input openings (2, 2a, 2b), and/or that at least one stowage chamber (14) is provided in the mixing element (13), and has only one input opening, while otherwise not being flow connected with the remaining chambers of the mixing element (13).
2. The mixer according to claim 1, characterized in that two compensation channels (4) are formed in the input part (1), which each connect the input openings (2, 2a, 2b) with each other.
3. The mixer according to claim 1 or 2, characterized in that the inlet channels are formed in such a way that the components to be mixed are guided into the mixing space separately from each other.
4. The mixer according to claim 3, characterized in that two input openings (2, 2a, 2b) are arranged diametrically opposite each other in the input part (1), wherein the inlet channels (7a) extend along a diagonal that connects the input openings (2, 2a, 2b) and are separated from each other by a partition wall (11) that runs transverse to the diagonal.
5. The mixer according to claim 3, characterized in that the inlet channels (7a) are formed in such a way that the components to be mixed at least sectionally envelop each other while being guided into the mixing space.
6. The mixer according to claim 1 or 2, characterized in that the inlet channels (7a) are flow connected with each other, so that the components to be mixed are guided into the mixing space together.
7. The mixer according to one of the preceding claims, characterized in that the at least one compensation channel (4) extends essentially like a circular arc between the input openings (2, 2a, 2b).
8. The mixer according to one of the preceding claims, characterized in that the at least one compensation channel (4) runs radially outside of the inlet channels (7a) .
9. The mixer according to one of the preceding claims, characterized in that the at least one compensation channel (4) and the inlet channels (7a) are formed as depressions or grooves in the input part (1), which are at least sectionally sealed by the mixer housing (13a).
10. The mixer according to one of the preceding claims, characterized in that the input part and the mixer housing (13a) are formed and adjusted to each other in such a way that the components to be mixed are deflected out of the input openings (2, 2a, 2b) from a flow direction extending parallel to the longitudinal axis of the mixer housing by 90° into a flow direction transverse to the longitudinal axis of the mixer housing (13a) .
11. The mixer according to one of the preceding claims, characterized in that the at least one flow wall (5) forms a seal with a disk- or funnel-shaped collar (15) of the mixer housing (13a) or the mixing element (13).
12. The mixer according to one of the preceding claims, characterized in that the input part (1) has a stowage space (21) that runs radially outside of the compensation channel (4) and/or of the inlet channels (7a) .
13. The mixer according to one of the preceding claims, characterized in that at least one of the input openings (2a, 2b) has allocated to it a deflection plate (20) and/or a flow direction sensor (22), which at least partially covers and/or laterally borders the corresponding input opening (2, 2a, 2b).
14. The mixer according to one of the preceding claims, characterized in that the mixing element (13) has at least one flow chamber (25), which is adjacent to the stowage chamber (14) and flow connected with the mixing space via a passage opening (25).
15. The mixer according to claim 14, characterized in that the cross section of the at least one flow chamber (25) lying perpendicular to the material discharge direction measures 80% to 120% of the cross section of the passage opening (25) lying perpendicular to the material discharge direction.
16. The mixer according to one of claims 14 or 15, characterized in that the at least one flow chamber (25) is bordered in the material discharge direction by a transverse wall (26), and that the transverse wall (26) has a transverse wall opening (27).
17. The mixer according to one of the preceding claims, characterized in that the cross section of the mixing element (13) lying perpendicular to the material discharge direction in the section of the stowage chamber (14) and/or flow chamber (24) measures 105% to 150% of the cross section of the mixing element (13) lying perpendicular to the material discharge direction in the following section.

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