DE102017117198A1 - mixer - Google Patents

Abstract

Mixer for mixing pasty components with a mixing sleeve (1) which extends along a longitudinal axis (L) and has at least one inlet, preferably two inlets (7), and one outlet (8), and with at least one in the mixing sleeve (1 ), which together with the mixing sleeve (1) defines a plurality of chambers (20, 21) which are arranged along a flow path from the inlets (7) to the outlet (8) behind and / or next to each other the chambers (20, 21) are delimited by transverse walls (17) extending transversely to the longitudinal axis (L) and by four side walls (13, 14, 18) each extending parallel to the longitudinal axis (L), and wherein adjacent chambers (20, 21) are in fluid communication with one another via passage openings (15, 16, 19) provided in the side walls (14, 18), the mixing element (2) having two side walls forming strips (13) separated by a further one Forming side walls and web (14) arranged perpendicularly to the strips (13), and in that a first group of chambers (20) has first passage openings (15) arranged in the web (14) and extending to a strip (13) , and a second group of chambers (21) having second passage openings (16) which are positioned at a distance from at least one strip (13) in the web (14).

Description

The invention relates to a mixer for mixing pasty and / or flowable components. In particular, the invention relates to a static mixer, i. a mixer in which the components to be mixed are not mixed by an actively driven mixing element, but to flow past a mixing element and are mixed in this case.

Such mixers are used inter alia for mixing with one another, in particular curing, components also in the dental field. These components are usually stored in containers or chambers of a cartridge to which the fixed or replaceable mixer can be attached. By discharging the components from the containers of the cartridge they are passed through the mixer and emerge from this mixed.

Examples of such mixers are made EP 0 815 929 B1 . EP 1 125 626 B1 . EP 1 312 409 B1 . EP 1 588 757 B1 . EP 2 133 138 B1 . EP 2 599 540 A1 EP 2 301 656 B1 . WO 2011/119820 A1 and EP 1 426 099 B1 known.

So is in EP 0 815 929 B1 discloses a mixer with a mixing sleeve extending along a longitudinal axis and having at least two inlets and an outlet. The mixer further includes a mixing element received in the mixing sleeve which, together with the mixing sleeve, defines a plurality of chambers arranged behind and / or next to one another along a flow path from the inlets to the outlet. The chambers are delimited by transverse walls each extending transversely to the longitudinal axis, as well as four side walls each extending parallel to the longitudinal axis. Adjacent chambers are in fluid communication with one another via passage openings provided in the side walls.

In this known mixer, depending on the components to be mixed, it may lead to an unsatisfactory mixing result if, for example, streaks of individual components pass through the entire mixer and escape from the outlet substantially unmixed.

To improve the mixing result and prevent unmixed areas in the EP 2 301 656 B1 proposed to provide first flow parts and second flow parts. While the first flow portions guide the components from the center to the exterior of the mixing element, the second flow portions direct the components from the exterior to the center of the mixing element. These flow parts should thereby reverse the direction of flow of parts of the components, but are extremely expensive to manufacture.

Also the EP 2 614 883 A1 describes a static mixer which has an improved mixing result. For this purpose, in addition to deflecting elements, so-called detaching elements are arranged on the radially outer sides of the mixing element, the detaching elements pointing inwards in the radial direction. This should compensate for different flow velocities of the components in the mixing element.

From the EP 2 133 138 B1 For example, a mixer is known which has a first series of mixing elements for dividing the component streams in a first direction, and a second series of mixing elements for dividing the component streams in a second direction.

One from the EP 1 125 626 B1 known mixer has several modifications of a rectangular basic structure of mixing chambers, which have inputs and outputs. One modification has a web which is inclined to the tube axis and which connects an input to an output in a mixing chamber in such a way that the flow through the web is deflected from the tube wall in the direction of the tube axis or conversely from the tube axis in the direction of the tube wall. Alternatively, the lengths of three adjacent chambers can be shortened, so that the number of inputs or outputs is reduced. The thus formed three modified chambers are arranged so that a pair of chambers, which are arranged along the tube axis in a row, two of these chambers and a third chamber, which is arranged laterally from the chamber pair, via two openings a connection between the two chambers of the couple.

The aforementioned mixers have to solve the problem of streaking problem very complex designed mixing elements, which are correspondingly expensive and expensive to manufacture. Such mixers are therefore only conditionally suitable for applications in which the components mixed with one another cure and the mixer is therefore used as a disposable product.

Based on this, it is an object of the present invention to provide a mixer of the type described above, which has a simple structure and allows thorough mixing of pasty and / or flowable components.

This object is achieved essentially with a mixer according to claim 1. The mixer has, in particular cuboidal, chambers which are arranged behind and next to each other and communicate with each other via passage openings. Along a flow path from the inlets to the outlet, ie along the path of the components through the mixer, the components flow through some of the chambers and are thereby mixed together.

According to a first aspect of the present invention, the mixing element in this case has two strips, which each form, in particular substantially closed, side walls and, in particular parallel to each other or converging, in the direction of the longitudinal axis of the mixer at a distance from each other. The strips are connected by a further side walls forming and perpendicular to the strip web arranged. The strips preferably form radially, i. starting from the center or center of gravity and from the longitudinal axis of the mixer laterally projecting, outer side walls of the chambers, which may rest against the inner wall of the mixing sleeve. By contrast, the web can divide the mixing space of the mixing sleeve into two areas as a separating element running parallel to the longitudinal axis. The strips and the web are preferably arranged to each other so that they form an H-shaped cross section (perpendicular to the longitudinal axis), wherein the web connects the strips in particular centrally. This basic structure of the mixing element with two strips and a web is, for example, in injection molding comparatively easy and inexpensive to produce. At the same time, this structure causes the mixing element to be comparatively stiff and stable, which facilitates the assembly of the mixing element into the mixing sleeve.

According to a further aspect of the invention, a first group of chambers, also chambers of the first group, have first passages arranged in the web, which extend up to the strips, and a second group of chambers, also chambers of the second group, have second ones Passage openings which are positioned at a distance from at least one strip in the web. In other words, the first passage openings extend to a radially outer region of the mixing space formed by the mixing sleeve, as defined by one of the strips, whereas the second passage openings are offset radially inward by one of the strips in the mixing space due to their arrangement. This different arrangement of the passage openings can effectively prevent streaks of the components to be mixed in the outer region of the mixing chamber can pass unmixed to the outlet. In particular, the first passage openings may be designed so that they, optionally interrupted by a further side wall, extend over the entire width of the mixing space from one of the strips to the other of the strips. The second passage openings may for example be designed such that they extend at a distance from the two strips, in turn optionally interrupted by a further side wall, over a radially inner region of the mixing space.

Preferably, the transverse walls are connected to the web and one of the strips. The transverse walls extend according to an embodiment not over the entire width of the web but, for example, only one of the strips to the middle of the web. As a result, about a quarter of the cross section of the mixing chamber is closed in the direction of the longitudinal axis. Transverse walls may be on either side of the ridge in a cross-sectional plane of the mixer, i. be provided at the same position along the longitudinal axis. It is preferred if the transverse walls are arranged offset to one another, i. a transverse wall extends on one side of the web from one of the strips to the center of the mixing space, and another transverse wall extends on the other side of the web from the other strip to the center.

Further side walls of the chambers may extend from the transverse walls towards the inlets, i. opposite to the flow direction of the components, extending parallel to the strips. These further side walls are preferably arranged centrally on the web in order to re-apply the halves of the mixing chamber divided by the web onto then e.g. To divide quarters of the mixing room.

Preferably, in this design of the mixing element in the region along the longitudinal axis, in which these further side walls are provided, one of the passage openings provided in the web. Conversely, for example, in the area along the longitudinal axis, in which the web is closed, passage openings in the other side walls available.

According to a preferred embodiment, the chambers of the first group and the chambers of the second group each have exactly four passage openings, two of which passages are formed in the web and two further passage openings parallel to the web in the other side walls, so that in particular parallel to the web extending passage openings open a parallel to the web extending flow direction. In other words, in these chambers, the passage openings, which are preferably arranged offset from one another along the longitudinal axis, are arranged in directions which are perpendicular to the longitudinal axis and to each other. This results in a thorough mixing of the components the entry of the components into the respective chamber of chambers, which are to the respective chamber in different quadrants (seen in a cross section perpendicular to the longitudinal axis) and held by the exit of the components from the respective chamber in chambers, to the respective chamber in different quadrants (seen in a cross section perpendicular to the longitudinal axis) are. In particular, the two passage openings formed in the web are provided as recesses in the web, while the two further passage openings extending parallel to the web can be provided as recesses in the walls running perpendicular to the web.

Some known mixers have the problem that at the beginning of the mixing process, one of the components enters the mixing chamber faster or in an excessive amount, so that an initial amount of the mixture does not consist of the desired mixing ratio of the components. This problem can i.a. be met so that the mixing sleeve and the mixing element form a third group of at least one chamber, the side wall closed as a stowage chamber and only one opening, which is formed as an inlet opening in a transverse wall has. In this stowage chamber, an initial amount of the components flowing into the mixer can be collected, so that only subsequent quantities of the components, which then usually have the correct mixing ratio, are mixed in and discharged from the mixer. Since the stowage chamber according to the invention has only one inlet opening, but otherwise is not fluidly connected to the other chambers, the components entering the stowage chamber are held there, so that they essentially no longer participate in the further mixing process.

It has been found to be particularly useful if at least one storage chamber is provided at the inlet end of the mixing element. In this embodiment, the leading component is not first passed through other chambers. In the division of the mixing space into four quadrants as described above by way of example (seen in a cross section perpendicular to the longitudinal axis), two e.g. quadrants offset from one another may be provided with storage chambers, while in the other two quadrants chambers of the first group or second group are provided.

The mixing sleeve and the mixing element preferably each form, in cross-section, four chambers arranged next to one another which are at least partially offset from one another in the direction of the longitudinal axis. In principle, however, more than four chambers can be arranged side by side.

The mixing sleeve may have a first section which is rectangular in cross-section, in which the mixing element is accommodated, and a second cross-sectionally circular section, on which the outlet is provided.

Also the e.g. can be connected with a cartridge end of the mixing sleeve may have a circular cross-section section. This cartridge-side section can be provided with connecting means for fastening the mixer to the cartridge, for example with bayonet elements or a thread, in particular a male threaded section.

Preferably, the mixing sleeve has an inlet section in which an insert, which has at least two nozzles forming the inlets, is sealed in the axial direction. The sealing of the insert relative to the mixing sleeve can be carried out such that the insert is pressed firmly into the mixing sleeve when the application pressure increases. It can also be provided circumferential lips, which invest more tightly depending on the internal pressure in the mixer to a sealing surface. When the insert is freely rotatable relative to the mixing sleeve, the sockets of the insert may engage corresponding sockets or openings of the cartridge without obstructing any relative rotation of the mixing sleeve required to secure the mixer to the cartridge.

Preferably, the nozzles of the insert via at least one compensation chamber forming and / or at least partially radially inwardly extending channels with the chambers flow connected. The arrangement and design of the channels can thus also help to solve or minimize the above-described problem known mixer with a leading component at the beginning.

If necessary, a plurality of first groups of chambers and a plurality of second groups of chambers may be arranged in the mixing element. It has been found particularly favorable to provide one to three first groups and one to three second groups of chambers in the mixing element.

It is further preferred to arrange the first group of chambers and the second group of chambers in the upper and / or middle region of the mixing element, viewed in the direction of discharge of the components. In other words, the first and the second group of chambers are arranged in the region of above 50% or above 70% of the axial length, again in the delivery direction of the components, of the mixing element. More preferably, the first and second groups of chambers are in the range of 50 to 95% of the Length of the mixing element arranged, again considered in Ausbringrichtung the components.

The invention will be explained in more detail by means of embodiments and with reference to the drawings. All described and / or illustrated features alone or in any combination form the subject matter of the invention, regardless of their combination in the claims or their relationships.

• 1a die Einzelteile eines erfindungsgemäßen Mischers nach einer ersten Ausführungsform in Seitenansicht,
• 1b die Einzelteile des Mischers nach 1a in einer weiteren Seitenansicht,
• 1c die Einzelteile des Mischers nach 1a in Perspektivansicht,
• 2a den Mischer nach 1a in Schnittansicht,
• 2b den Mischer nach 1a in einer weiteren Schnittansicht,
• 2c den Mischer nach 1a in Draufsicht,
• 3 in Perspektivansicht Komponenten des Mischers nach 1a mit vergrößerten Details,
• 4a das Mischelement eines Mischers nach einer zweiten Ausführungsform der Erfindung in Perspektivansicht,
• 4b das Mischelement nach 4a in Schnittansicht, und
• 5 eine Perspektivansicht eines Mischers mit einem Mischelement, einem Einsatz und einer Mischhülse.

They show schematically:

• 1a the individual parts of a mixer according to the invention according to a first embodiment in side view,
• 1b the items of the mixer 1a in a further side view,
• 1c the items of the mixer 1a in perspective view,
• 2a after the mixer 1a in sectional view,
• 2 B after the mixer 1a in a further sectional view,
• 2c after the mixer 1a in plan view,
• 3 in perspective view components of the mixer after 1a with enlarged details,
• 4a the mixing element of a mixer according to a second embodiment of the invention in perspective view,
• 4b the mixing element after 4a in sectional view, and
• 5 a perspective view of a mixer with a mixing element, an insert and a mixing sleeve.

In the first embodiment according to the 1a to 3 shown static mixer is composed essentially of three components, namely a mixing sleeve 1 , a mixing element 2 and a mission 3 ,

The mixing sleeve 1 is an elongated component that extends along a longitudinal axis L extends. The mixing sleeve 1 has one in the 1a to 1c lower inlet area 4 having a substantially circular cross-section, a central region of rectangular cross-section having a mixing space 5 defined, and a Ausbringende 6 which in turn has a substantially circular cross-section. The inlet area 4 can be provided as indicated in the illustrated embodiment with a threaded portion or the like fastening means for connecting the mixer with a cartridge and with an external profiling.

The use 3 is in the inlet area 4 freely rotatable but axially firmly received and locked, for example. The use 3 is with two neck 7 provided, which form inlets of the mixer. That the use 3 opposite applicators 6 is with an outlet 8th Mistake. In the illustrated embodiment is between the nozzle 7 a partition 9 formed with one over the mixing sleeve 1 protruding coding element 10 is provided that can engage in a manner not shown to guide the mixer during manufacture of the compound with a cartridge in a corresponding opening of the cartridge. The pillars 7 are over partially radially or arcuately inward leading channels 11 with the mixing room 5 flow-connected.

The mixing element 2 is in the rectangular section of the mixing sleeve 1 recorded and points to his in the 1a to 1c lower end of a plate 12 with a central entrance opening 12a on, through which the components to be mixed from the channels 11 in the mixing room 5 reach. In particular, the mixing element 2 into the mixing sleeve 1 insertable and is through the plate 12 held in the axial direction so that a displacement of the mixing element 2 in the direction of the dispensing end 6 the mixing sleeve 1 , For example, by the application pressure of the components, is prevented. Parallel to the longitudinal axis L two stripes extend 13 of the mixing element 2 over a footbridge 14 are interconnected so that in a cross section perpendicular to the longitudinal axis L the mixing element 2 H-shaped. The Stripes 13 extend in the illustrated embodiment over the entire width of the mixing chamber 5 in the area of the mixing sleeve with rectangular cross-section.

The jetty 14 is provided with a plurality of passage openings, which are rectangular in the illustrated embodiment. First passages 15 extend over the entire width of the web 14 and thus border on the two strips 13 at. Second passages 16 In contrast, do not extend over the entire width of the web 14 and are thus at a distance to the strips 13 positioned. This is also out 2a and the enlarged detail A of 3 seen.

At the footbridge 14 are several to each other in the direction of the longitudinal axis L staggered transverse walls 17 formed in the illustrated embodiment of one of the strips 13 until about the middle of the bridge 14 pass. In one to the longitudinal axis L vertical cross-sectional plane is on one side of the web 14 a first transverse wall 17 present while on the other side of the jetty 14 a transverse wall offset from the first transverse wall 17 is provided. In other words, for example, in the enlarged detail view in FIG 3 the front partition 17 with the right strip 13 connected while on the back of the dock 14 provided transverse wall 17 with the left strip 13 connected is.

From the transverse walls 17 sidewalls extend 18 parallel to the longitudinal axis L and perpendicular to the bridge 14 in the figures down, ie in the direction of the inlet area 4 of the mixer. In the axial direction, these side walls extend 18 not up to the following transverse wall 17 but are through further passages 19 interrupted, with the passage openings 15 . 16 and the passages 19 such in the direction of the longitudinal axis L offset from each other, that the passage openings 19 are provided in the areas where the jetty 14 is closed, ie no openings 15 . 16 having. Conversely, the passage openings 15 . 16 arranged in the areas where no passage openings 19 in the side walls 18 available.

The mixing sleeve 1 , the Stripes 13 , the bridge 14 , the transverse walls 17 and the side walls 18 define with it chambers 20 . 21 , which are flowed through by the components to be mixed in the flow path from the inlets to the outlet. The length of the chambers 20 . 21 in the direction of the longitudinal axis L is determined by the distance between two parallel to the longitudinal axis L one behind the other transverse walls 17 Are defined. The chambers differ essentially by the differences of the openings 15 . 16 in first chambers 20 and second chambers 21 as well as by their arrangement within the mixer. So are adjacent chambers in the direction of the longitudinal axis L arranged mutually offset by half a chamber length.

In this arrangement, each of the chambers is with two passage openings 15 respectively. 16 and with two openings 19 Mistake. Each of the chambers is above the passages 15 respectively. 16 with one along the longitudinal axis L Chamber recessed by half a chamber length and chamber advanced by half a chamber length on the other side of the web 14 in fluid communication. In addition, each chamber is above the passages 19 with one along the longitudinal axis L Chamber recessed by half a chamber length and chamber advanced by half a chamber length on the same side of the web 14 in fluid communication. This means that each chamber has four passages 15 . 16 . 19 connected with four different other chambers. The deflection, splitting into partial flows and bringing together the partial flows of the components during the passage through the various chambers causes an intensive mixing of the components.

In addition to these essentially structurally designed chambers 20 . 21 are in the region of the inlet end and the outlet end of the mixer according to incomplete chambers with only one or with only two passages available.

In the embodiment of the 4a and 4b is the mixing element 2 modified from the first embodiment in that in the vicinity of the plate 12 storage chambers 22 are formed, which have only an inlet but no outlets. In these storage chambers 22 For example, the initial amount of a prone component may still be prior to entering the chambers 20 . 21 be collected and stored without this initial quantity participates in the further mixing process.

In the 5 is another embodiment of the mixing element 2 shown. In comparison to the embodiments described above, the mixing element shown here comprises 2 both a rectangular area 2a as well as a helical area 2 B extending in the direction of application of the components to the rectangular area 2a followed. This has the advantage that so the length of the mixing element 2 can be adapted to the respective application requirements. Because the rectangular area 2a has a good mixing, but a high application pressure, while the helical region 2 B Providing a lower application pressure can be achieved by adjusting the lengths of the rectangular area 2a and the helical area 2 B the mixing effect, the length and the Ausbrindruck be adapted to the particular application requirements.

LIST OF REFERENCE NUMBERS

1

mixing sleeve

2

mixing element

2a

rectangular area

2 B

helical area

3

commitment

4

inlet area

5

mixing room

6

discharge end

7

Nozzle (inlet)

8th

outlet

9

partition wall

10

coding

11

channel

12

Plate

12a

central entrance opening

13

strip

14

web

15

Through opening

16

Through opening

17

partition

18

Side wall

19

Through opening

20

chamber

21

chamber

22

storage chamber

L

longitudinal axis

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• EP 0815929 B1 [0003, 0004]
• EP 1125626 B1 [0003, 0009]
• EP 1312409 B1 [0003]
• EP 1588757 B1 [0003]
• EP 2133138 B1 [0003, 0008]
• EP 2599540 A1 [0003]
• EP 2301656 B1 [0003, 0006]
• WO 2011/119820 A1 [0003]
• EP 1426099 B1 [0003]
• EP 2614883 A1 [0007]

Claims (11)

Mixer for mixing pasty components with a mixing sleeve (1) which extends along a longitudinal axis (L) and has at least one inlet, preferably two inlets (7), and one outlet (8), and with at least one in the mixing sleeve (1 ), which together with the mixing sleeve (1) defines a plurality of chambers (20, 21) which are arranged along a flow path from the inlets (7) to the outlet (8) behind and / or next to each other the chambers (20, 21) are delimited by transverse walls (17) extending transversely to the longitudinal axis (L) and by four side walls (13, 14, 18) each extending parallel to the longitudinal axis (L), and wherein adjacent chambers (20, 21) are in fluid communication with one another via passage openings (15, 16, 19) provided in the side walls (14, 18), characterized in that the mixing element (2) has two side walls forming strips (13) through one more e side walls forming and perpendicular to the strips (13) arranged web (14) are connected, and that a first group of chambers (20) in the web (14) arranged first passage openings (15) extending up to a strip ( 13), and a second group of chambers (21) having second passage openings (16) which are positioned at a distance from at least one strip (13) in the web (14). Mixer after Claim 1 , characterized in that the web (14) connects the strips (13) in the middle. Mixer after Claim 1 or 2 characterized in that the transverse walls (17) are connected to the web (14) and one of the strips (13), and that from the transverse walls (17) towards the inlets (7) parallel to the strips (13) Side walls (18) extend. Mixer according to one of the preceding claims, characterized in that chambers (20) of the first group and the chambers (21) of the second group each have exactly four passage openings (15, 16, 19), of which two passage openings (15, 16) in the web (14) are formed and two further passage openings (19) parallel to the web (14) extend. Mixer according to one of the preceding claims, characterized in that the mixing sleeve (1) and the mixing element (2) form a third group of at least one chamber (22), the side walls (13, 14, 18) closed as a storage chamber (22) only one opening, which is formed as an inlet opening in a transverse wall (17) has. Mixer after Claim 5 , characterized in that at least one storage chamber (22) at the inlet end of the mixing element (2) is provided. Mixer according to one of the preceding claims, characterized in that the mixing sleeve (1) has a first rectangular cross-section portion in which the mixing element (2) is accommodated, and a second circular cross-section portion (6), at which the outlet (8) is provided. Mixer according to one of the preceding claims, characterized in that the mixing sleeve (1) and the mixing element (2) in cross section each form four juxtaposed chambers (20, 21, 22) which at least partially offset in the direction of the longitudinal axis (L) to each other are. Mixer according to one of the preceding claims, characterized in that the mixing sleeve (1) has an inlet section (4) in which an insert (3) having at least two nozzles (7) forming the inlets is sealed and preferably opposite the mixing sleeve (1) freely rotatable, is fixed. Mixer after Claim 9 , characterized in that the connecting pieces (7) of the insert (3) via at least one compensation chamber forming and / or at least partially radially inwardly extending channels (11) with the chambers (20, 21, 22) are flow connected. Mixer according to one of the preceding claims, characterized in that the chambers (20) of the first group and the chambers (21) of the second group are arranged in the delivery direction of the components, middle and / or upper region of the mixing element (2).

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