JPH0352321B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite nozzle for guiding the merging of at least two fluid reaction components for the production of plastics, in particular foam plastics, for the purpose of initiating a reaction by mixing, as well as a composite nozzle for the purpose of initiating a reaction by mixing. Concerning how to operate. The combined nozzle in this case comprises: a casing; a component supply conduit led into the casing; a casing bore arranged in the casing and having a coaxial outlet passage at its end face; coaxial within the casing bore. at least one needle sleeve guided coaxially; a nozzle needle coaxially guided within the needle sleeve; arranged between the surrounding wall of the casing bore and the needle sleeve and between the needle sleeve and the nozzle needle; an inner chamber to which one component supply conduit is connected, and when the nozzle is closed, the nozzle needle cooperates with the inner end surface of the needle sleeve, and the outer end surface of the needle sleeve In cooperation with the inner end surface of the casing bore, they each form a sealing seat, whereas when the nozzle is open, the coaxial nozzle opening of the needle sleeve is released from the nozzle needle and the needle The nozzle opening is formed between the outer end surface of the sleeve and the inner end surface of the casing hole.

The compound nozzle built into the spray gun is
Its effectiveness has been demonstrated in the field of spray painting technology using so-called "two-component lacquers". In this case, there is no need to place any emphasis on accurately metering and guiding the components together at the beginning and even at the end of the mixing process.

It is easy to imagine that composite nozzles of this type can also be used for the production of solid or porous plastics. In relatively simple fields of application, such as polyurethane insulating foam plastics technology, the known composite nozzles are sufficient to achieve the desired purpose. However, the use of known composite nozzles in the field of producing high quality plastic parts, particularly by mold forming using molds, will inevitably reach its limits in the near future for various reasons.

In a two-component spray gun, in particular for epoxy resin injection, which is known from German Patent No. 1 251 190, two coaxial liquid nozzles are first widened and then tapered again. A front piece with a mixing chamber is arranged on the end face, which opens into a mixing chamber, in this case with a coaxial nozzle opening, in which the nozzle opening A cone facing the is provided. Furthermore, compressed air nozzles are arranged inside and outside the mixing chamber, by means of which air is blown directly into the mixture or the exiting mixture jet is regulated. The metered convergence of each component at the beginning and end of the spraying process is not guaranteed. This is because, since the operation is performed via the hand lever, it is not possible to obtain a sufficient operation speed. A mixing chamber having such a complicated structure cannot be sufficiently cleaned without using a detergent.

The two-component spray gun used for coating polyester resins according to German Patent Application No. 1086598 also has the drawbacks mentioned above. In this known example, a first nozzle and a second nozzle are arranged fixedly one after the other and can be closed by a common nozzle needle, in which case also a further coaxial air nozzle is provided. ing. The first embodiment of this spray gun has the disadvantage that one of the components precedes the nozzle when it opens and lags behind it when it closes, resulting in the components remaining unmixed. In addition to this disadvantage, the second embodiment also has the disadvantage that cleaning with a detergent must be carried out.

In the technique disclosed by German Patent Application No. 2252008, i.e. for guiding the merging of several components such as polyols and isocyanates, a plurality of coaxial The mixing chamber of this known example is expanded or contracted by means of a spring-supported insert depending on the pressure of the main components, the nozzle opening being able to absorb the component pressure acting against the pressure spring. It is opened and closed by. This type of control system can no longer meet modern requirements because the nozzle opening/closing timing is imprecise. If this method is adopted, the mixing chamber is completely emptied with the nozzle closed, but a fully reacted mixture film remains between the two radial surfaces, so that over time A mixture layer will be formed within this mixing chamber. The main components reach the mixing chamber through the controlled gap. In this known concept, only a very small nozzle throughput speed can be adjusted for the main component. The reason for this is that the diameter is relatively large, and
The permissible control gap width must be set in such a way that particles are not filtered out in the control gap, which could result in malfunctions.

Additionally, Federal Republic of Germany Patent Application Publication No. 3 (corresponding to U.S. Pat. No. 3,771,963)
No. 2,031,739 discloses a method and a device for producing foam materials or homogeneous plastics from at least two components that react with each other, each component being introduced separately into a mixing zone. are brought into close proximity and merged just before being injected into the mixing zone, and both are fed into the mixing zone through a nozzle under negative pressure and mixed within a residence time of at least 1/1000 second within the mixing zone; This mixture is then discharged. In devices implementing this method, the supply conduits are guided together just before the nozzle opening and reach a common compound nozzle facing into the mixing chamber. This device is equipped with a component pressure control device that acts against the tension spring, but the precision of this control device is low. Furthermore, in this case one component is preferably fed centrally through the nozzle needle, and can only be shut off on the upstream side by means of a spring-loaded pressure valve. Secondary dripping is therefore inevitable, resulting in contamination of the components. Another drawback is that this composite nozzle
One of the reasons is that it is not suitable for application to RIM technology. This is because when using this composite nozzle, there is a risk that the central feed hole may become clogged with the layer of mixed material.

All these known multi-nozzle devices have to be cleaned with detergents, have imprecise actuation at the beginning and end of the component merging guide, and therefore cannot handle small amounts of the mixture. It suffers from the disadvantage that it cannot be manufactured reproducibly.

The object of the present invention is to improve a compound nozzle of the type mentioned at the outset and the method of its operation so that the components can be guided in merging precisely at the beginning and end of the mixing process according to their dosing ratios. to ensure that no one component takes the lead or lags behind, to allow detergent-free operation, and to be able to reproduce even very small amounts of components for the purpose of starting the reaction by mixing. The purpose is to make it possible to guide the annexation.

In the composite nozzle of the present invention proposed to solve this problem, the nozzle needle has a coaxial pin, and the cross-sectional shape and dimensions of this pin are aligned with the nozzle opening of the needle sleeve and the outlet passage. In the closed state, the outlet channel is filled up to the outlet by means of this pin, and a forced control device 21 is assigned to the nozzle needle as well as to the other end of the needle sleeve. .

By placing a pin at the tip of the nozzle needle and giving this pin a predetermined shape,
First of all, a self-cleaning mode of construction in the compound nozzle is achieved. If the nozzle needle and needle sleeve are forcibly controlled, the opening and closing movements of the nozzle orifice can be precisely synchronized with each other, resulting in precise distribution of each reactant from the first drop to the last. We will guide you through merging based on quantity ratio,
Moreover, at that time, it is possible to adjust so that one component does not take the lead or lag behind.

While the dimensions of the outlet passage of the compound nozzle, which is filled by the pin in the closed state, can be kept very small, all the components flow through this common outlet passage, so that especially small units of It is also possible to nozzle a quantity of components per hour, thus making it possible to produce very small molded parts having a weight of only a few grams.

Thus, according to the novel technique of the present invention,
A new field of application for the production of molded parts made of plastics, in particular polyurethane foam plastics, is disclosed.

It is advantageous if the nozzle opening of the needle sleeve and the outlet channel following it have the same diameter, to which the diameter of the pin is adapted with certain tolerances. However, the diameter of the nozzle opening may be larger than the diameter of the outlet passage, in which case the diameter of the pin must be increased or decreased accordingly.

According to one embodiment of the invention, a compound nozzle has a plurality of concentric needle sleeves.

According to this measure, it is made possible to simultaneously guide three or more components or one component and several components simultaneously through different nozzle openings, so that a boundary layer exists between the individual jets. resulting in multiple contact zones.

It is advantageous if one or more needle sleeves and nozzle needles are each assigned a stroke stop that can be adjusted independently of one another. With this measure, the respective nozzle pressures and thus the respective jet velocities can be synchronized particularly easily. The adjustment ability of the stroke adjustment stop can also be fully exerted by mechanical or hydraulic or pneumatic means, especially during the mixing process. In this case, the stroke adjustment stop is preferably adjusted by means of a remote control, for example a control desk. According to a special embodiment, the stop adjustment is carried out automatically, for example depending on the respective desired component pressure, and a suitable program for this can also be provided in advance.

According to one embodiment of the invention, the forced control device consists of a hydraulic drive.

With this embodiment of the piston and cylinder, extremely rapid switching on and off of the nozzle opening can take place, so that leading or lagging of one component is completely avoided.

In this case, it is possible to use the reaction component itself as the hydraulic medium; the nozzle needle and the needle sleeve are opened by the pressure of the reaction component, but their closing is effected by a customary hydraulic medium. In this case as well, work is performed against the stopper, so this embodiment also relates to a forced control system.

Each component pressure and switching speed means that each component joins at the first moment when the nozzle opening is opened,
They can be synchronized with each other so that upon closure, a precise interruption occurs so that no component remains alone.

According to a further embodiment of the invention, a component return conduit and a shutoff device are assigned to the combined nozzle, the shutoff device consisting of a hydraulic drive and a nozzle needle and one or more needle sleeves. It is connected to a hydraulic drive system.

In this way, the technique of circulating the components during the downtime, which is generally known in polyurethane foam molding machines, can be applied to the composite nozzle according to the invention.

In order to carry out an unseparated conveyance when switching the circulation circuit to nozzle operation and vice versa, it is advantageous if the slider of the shut-off mechanism is provided with a pin. Note that this shutoff mechanism can also be used as a throttling mechanism for adjusting the circulation circuit pressure at the same time.

The nozzle needle and the needle sleeve or sleeves can also be used as switching elements by being provided with an extension or a groove or channel which opens the passage towards the return conduit only in the closed state of the nozzle opening.

The nozzle opening for the reaction components to be fed concentrically is preferably between 30° and 150°.
With a clearly lateral directional component of between 45° and 135°, this nozzle opening is reliably sealed in the closed state.

If more than two components are supplied, the expense required to produce a corresponding number of concentric needle sleeves becomes significant due to fairly limited tolerance ranges, and in addition, in this case leakage resistance to becomes weaker.

According to one embodiment of the invention, therefore, a supply conduit for the additional component is provided, the opening of which is directed into the guide hole of the nozzle needle, and the nozzle needle is provided with a step, in the open position of the nozzle needle. It has been proposed to use this step as a control edge in such a way that the opening is free from the step and in the closed position is sealed off by a shaft section with a larger diameter.

The advantage of the composite nozzle according to this embodiment is that it has fewer moving parts and therefore fewer sealing surfaces, so it can be manufactured easily and without any problems. The feed stream of additional components is released or dripped by the step of the nozzle needle. It is clear that in this case the supply conduits for several additional components can be arranged in a similar manner. In this case, it is advantageous if the openings of each conduit are arranged at the same mutual angular spacing. Note that it is also possible to allocate a plurality of openings to one supply conduit.

The main components of the plurality of main components that do not react with the additional components are guided through an internal chamber located in the needle sleeve. This is because a mixture of main and additional components remains in this interior chamber after each working cycle.

If a plurality of mutually reacting additional components or a plurality of additional components reacting in part with one main component and in part with the other main component are to be supplied, an opening in the supply conduit is required. It is also possible to arrange the part in the region of the sealing seat of the needle sleeve with the housing bore. In this case, it is clear that several openings can be provided for one supply conduit or that several openings and supply conduits can be arranged for several additional components.

In this embodiment, the additional components supplied in this manner are guided together with the other components only just before they are ejected from the compound nozzle.

In a further embodiment of the invention, the composite nozzle is combined with the forming tool via a starting guide and a corresponding connecting element.

The advantage of this embodiment is that the compound nozzle, which is otherwise stationary, can be brought into abutment against a forming tool that is moved periodically along it, for example on a turntable. . In this case, it is advantageous if a safety device known per se is provided, which only releases the mixing process when the forming tool is closed and the composite nozzle is sealed. For example, a slide guide is used as the contact guide, and the contact operation itself can be carried out, for example, by means of an associated hydraulic drive.

In this embodiment, a stability chamber is provided within the surrounding wall of the forming tool, located in front of the mold cavity;
Advantageously, the inlet opening of the stabilizing chamber is matched with the outlet opening of the nozzle in the coupling position of the composite nozzle and is made closable by means of a closing slide integrated in the enclosure of the forming tool.

If such measures are taken, the outlet opening of the compound nozzle will be sealed when the compound nozzle is connected to the forming tool. The closing slide can be configured as an opening/closing slide. However, this closing slide can also open against the initial stress under the pressure generated under the mixture and can also be designed as an ejector for the residual mixture reacted in the stability chamber. This closing slide can also be constructed in such a way that, for example, a stable chamber is used as a guide. The travel of the closing slide can be adjusted, for example, by means of an adjustable stop. It is advantageous if the axis of the closing slide is aligned with the axis of the compound nozzle, but it may also have any other orientation, in particular an arrangement in which these two axes are at right angles to each other. It is possible. The closing slide can be operated hydraulically or mechanically and is preferably automatically controllable.

In the process according to the invention for guiding the merging of at least two fluid reaction components to form plastics, in particular foam plastics, with the aim of starting the reaction by mixing, the reaction components are fed in metered quantities and one reaction is carried out. The components are concentrically guided in the center and one or more other reaction components surround the first reaction component, and during this merging guidance there is a gap between the central jet and the one or more concentric jets. The relative velocity of is maintained.

This method provides the best conditions for starting a successful mixing.

It is advantageous to have high relative velocities that create turbulence in the boundary layer between each jet.

This turbulent flow functions to sufficiently exchange particles between both jets. If the individual reaction components are difficult to mix due to their composition, it may be necessary to connect a mixing chamber later. In this case, it is often sufficient that the mixture jet impinges on the corresponding surface.

According to one embodiment of the method according to the invention, if more than two jets are present, another jet is supplied or interrupted at any time.

This measure makes it possible to obtain conditions for imparting special properties to the finished product by varying the dosage ratios or by adding or removing further components during the mixing process. In this case, it is essential that appropriate needle sleeves be separately forcefully controllable.

The composite nozzle according to the invention will now be described in detail with reference to several embodiments shown in the attached longitudinal cross-sectional views: The composite nozzle shown in FIGS. 1 and 2 has a nozzle casing 1. supply conduits 2, 3 for the two main components (isocyanate and polyol) and one additional component (e.g. promoter)
a supply conduit 44 with an opening 45 for
It is introduced into the nozzle casing 1. A casing hole 4 is arranged inside the nozzle casing 1, and a base portion 46 is disposed inside the casing hole 4.
A needle sleeve 5 having a
a nozzle needle 6 guided in the sleeve or in an axial bore 47 arranged within the sleeve;
are concentrically surrounded by this needle sleeve 5. The component supply conduit 2 opens into an interior chamber 7 formed between the inner wall 8 of the casing bore 4 and the needle sleeve 5 . Component supply conduit 3
is arranged inside the needle sleeve 5 and opens into an inner chamber 9 through which the nozzle needle 6 passes.
This nozzle needle 6 has a step 48 which acts as a control lip, whereas when the nozzle needle 6 is raised the supply conduit 44 is open and in free communication with the interior chamber 9. , the thick shaft section 49 seals off the opening 45 of the supply conduit 44 in the closed position. The nozzle needle 6 furthermore has a tapered sealing surface 10, which in the closed state shown in FIG. 1 cooperates with the inner end surface 11 of the needle sleeve 5 to form a sealing surface 12. On the other hand, the outer end surface 13 of the needle sleeve 5 and the inner end surface 14 of the casing hole 4 also form a seal seat 15. When the nozzle needle 6 occupies this position, the pin 16 disposed at its tip
completely fills the outflow passage 17. In other words, the pin 16 reaches the outlet 18. In the open state shown in FIG. 2, the nozzle needle 6 or its pin 16 is released from the nozzle needle opening 19, and there is no space between the outer end surface 12 of the needle sleeve 5 and the inner end surface 13 of the casing bore 4. Ring-shaped nozzle opening 20
is formed. A forced control device 21 is assigned to the needle sleeve 5 and the nozzle needle 6. This forced control device 21 is a hydraulic drive device 2
2, 23, and the driving device 22, 23
a cylinder chamber 24 disposed in the needle sleeve 5; a piston 25 disposed in the nozzle needle 6; or a piston 27 forming an enlarged portion of the casing hole 4 and disposed in the needle sleeve 5;
It is formed from supply and discharge sections 28 and 29. A relatively weak spring (not shown) acts on the pistons 25, 27, and this spring acts on the nozzle needle 6 and the needle sleeve 5 when no hydraulic pressure is present.
and is used to keep it closed. The stroke adjustment stops 30, 31 assigned to the needle sleeve 5 and the nozzle needle 6 are connected to the insert 5 which closes the hydraulic cylinder chamber 26 in the housing bore 4.
0.0. The return conduits 32, 33 guided out of the inner chambers 7, 9 are
It can be shut off by valves 34, 35 arranged in the casing 1. These valves 34, 35 are connected to pistons 38 to 39 and cylinders 40 to 4.
It is formed by hydraulic drive devices 36 and 37 consisting of 1 and 1. The flow cross section can be adjusted by stroke adjustment stops 42, 43. Return conduits and shutoff mechanisms for additional components are not shown.

This composite nozzle is combined with a forming tool 51. The molding tool 51 consists of two mold halves 52, 5.
3, forming a mold cavity 54. The mold half 52 on the side facing the compound nozzle has a centering cutout 55 that fits into the centering addition 56 of the compound nozzle. This forming tool 51 is fixed in position, whereas the composite nozzle is movable towards the forming tool 51 inside schematically illustrated abutment guides 57, 58. Centering addition 56 and centering notch 55 have matching surfaces 59, 60 that meet in the closed state. A stability chamber 61 is provided in the other mold half 53 and extends axially towards the centering recess 55 .
This stable chamber 61 also serves as a guide for a closing slide 62, to which a hydraulic drive 63 and an adjustable stop 64 are assigned. In this embodiment, the closing slider 62 only has an opening/closing function, but it can also be used as an ejector for removing the residual mixture that hardens within the stability chamber 61. This stability chamber 61 is
If the compound nozzle occupies a detached position (not shown), it is completely filled by the closing slide 62 at the earliest until it abuts the forming tool 51, and in the abutment position the compound nozzle is completely filled until the nozzle process is started. Seal the outlet opening 18.
In the abutting position of the compound nozzle, the outlet opening 18 and the inlet opening 65 of the stability chamber 61
are directly adjacent to each other and located within the same axis. The opening 66 of the supply conduit 67 for further additional components (for example dyes) opens in the area of the sealing seat 15 of the needle sleeve 5 with the housing bore 4 .

The composite nozzle shown in FIGS. 3 and 4 is the first
The points that are different from the composite nozzle shown in Figures and Figure 2 are as follows.
While the nozzle needle 103 is surrounded in the housing bore 101 of the casing 102 by a needle sleeve 104, two further needle sleeves 105, 1 are guided concentrically with respect to each other.
It is also surrounded by 06. Nozzle needle 103 and needle sleeve 104,1
05, 106 are respectively assigned separate adjustable stops 107, 108, 109, 110. Having already explained the composite nozzle shown in FIGS. 1 and 2, there is no need to explain the structure and mode of operation of the embodiment according to FIGS. 3 and 4 any further.

Method Example In this example, a composite nozzle according to FIGS. 1 and 2 was used, but no combination with a forming tool was carried out. Note that to make the method easier to understand, the supply of additional components was omitted by blocking the supply conduit 44.

From the storage container, the polyol and isocyanate components are delivered in a 2:1 ratio by means of a high-pressure metering pump to the composite nozzle via the supply conduits 2, 3, and in the closed state of the composite nozzle, a shut-off mechanism 34, 3
5 is open, the return conduits 32, 33
reflux into the storage container via the These shut-off mechanisms 34, 35 are adjusted in such a way that the respective circuit pressure is set to 200 bar for the polyol component and 40 bar for the isocyanate component by throttling action. The amount of mixture required to produce one molded part is 20 grams. Since the dosing pumps deliver 30 grams of polyol per second and 15 grams of isocyanate per second, force controller 21 must be adjusted for a nozzle treatment time of 0.44 seconds. When the forced control device 21 is activated in this way, the load on the pistons 25, 27 is reduced in such a way that the needle sleeve 5 and the nozzle needle 6 are lifted percussively and the nozzle openings 19, 20 are released. It is done. Needle sleeve 5 is stopper 3
0, the nozzle opening 20 is open, and when the nozzle needle 6 is in contact with the stopper 31, the nozzle opening 19 is open. If the injection pressure is selected appropriately, taking into account the structural dimensions and the different viscosities of the components, both components will be injected into the outlet passage 17 from the first drop after opening of the nozzle openings 19, 20.
merging is achieved with precise dosing ratios. Similarly, this effect is also noticeable when closed. The polyol-to-isocyanate nozzle treatment takes place immediately upon ejection at a velocity of 120 to 30 meters per second, thus creating a relative velocity of 90 meters per second between the central polyol jet and the concentric isocyanate jet. Therefore, turbulence is generated in the boundary layer between both jets.

[Brief explanation of drawings]

FIG. 1 shows a closed state of a composite nozzle according to a first embodiment of the invention combined with a forming tool;
2 is a diagram showing the open state of the compound nozzle according to FIG. 1, FIG. 3 is a diagram showing the open condition of the compound nozzle according to the second embodiment, and FIG. 4 is a diagram showing the compound nozzle in the closed condition according to FIG. 3. It is a diagram. 1,102...Casing, 2,3,44,6
7... Supply conduit, 4,101... Casing hole,
5,104,105,106... Needle sleeve, 6,103... Nozzle needle, 7,9...
Inner chamber, 8... Inner wall, 10... Seal surface, 11, 1
4... Inner end surface, 13... Outer end surface, 12, 15...
Seal seat, 16...pin, 17...outflow passage, 1
8... Outlet, 19, 20... Nozzle opening, 21... Forced control device, 22, 23, 36,
37, 63... Drive device, 24, 26... Cylinder chamber, 25, 27, 38, 39... Piston, 2
8, 29... Supply and discharge section, 30, 31, 4
2, 43... Stroke adjustment stopper, 32, 33...
Return conduit, 34, 35...Valve (shutoff mechanism), 40,
41... Cylinder, 45, 66... Opening, 46
... Base part, 47 ... Perforation part, 48 ... Step part, 4
9... Shaft division, 50... Insert, 51...
Molding tool, 52, 53... Mold half body, 54... Mold hollow chamber, 55... Centering notch, 56... Centering addition portion, 57, 58... Contact guide, 59, 60...
Matching surface, 61... Stability chamber, 62... Closing slider, 64, 107, 108, 109, 110...
Stopper, 65... Inlet opening.

Claims (1)

[Claims] 1. At least two flowable reaction components for producing a plastic, in particular a foam plastic, comprising:
This is a composite nozzle for guiding a mixture for the purpose of starting a reaction by mixing, which includes a casing 1; component supply conduits 2 and 3 guided into the casing 1; and a coaxial outlet disposed within the casing 1. a housing bore 4 having a channel 17 at the end face 14; at least one needle sleeve 5 coaxially guided in the housing bore 4; coaxially guided in the needle sleeve 5. a nozzle needle 6; arranged between the surrounding wall 8 of the casing bore 4 and the needle sleeve 5 and between the needle sleeve 5 and the nozzle needle 6, in each case one component supply conduit 2;
3 are connected, and in the closed state of the nozzle, the nozzle needle 6 cooperates with the inner end surface 11 of the needle sleeve 5 and the needle sleeve 5. The outer end surface 13 of the casing hole 4 cooperates with the inner end surface 14 of the casing hole 4 to form seal seats 12 and 15, respectively, while when the nozzle is open,
Coaxial nozzle opening 19 of needle sleeve 5
is released from the nozzle needle 6, and a nozzle opening 20 is formed between the outer end surface 13 of the needle sleeve 5 and the inner end surface 14 of the casing hole 4. 16, the cross-sectional shape and dimensions of this pin 16 are matched to the cross-sectional shape and dimensions of the nozzle opening 19 of the needle sleeve 5 and the outlet passage 17, and in the closed state, the outlet passage 17 is A compound nozzle characterized in that the pin 16 fills up to the outlet 18, and a forced control device 21 is assigned to the other end of the nozzle needle 6 and the needle sleeve 5. 2. Multiple concentric needle sleeves 104,1
05, 106. The composite nozzle according to claim 1, further comprising: 3 A plurality of stroke adjustment stoppers 30, 31, 107, 108, 109, 1 that can be adjusted independently of each other
10 is one or more needle sleeves 5,1
04, 105, 106 and nozzle needle 6, 10
3. The composite nozzle according to claim 1 or 2, characterized in that the composite nozzle is assigned to 3 and 3. 4 The forced control device 21 is a hydraulic drive device 22,
23. The composite nozzle according to any one of claims 1 to 3, characterized in that the composite nozzle is composed of 23. 5 Component return conduits 32, 33 and blocking mechanisms 34, 3
5 is assigned, and in this case, the cutoff mechanism 3
4 and 35 are composed of hydraulic drive devices 36 and 37, which are connected to the hydraulic drive devices 22 and 23 of the nozzle needle 6 and one or more needle sleeves 5. A composite nozzle according to any one of claims 1 to 4. 6 A supply conduit 44 for the additional component is provided, the opening 45 of which faces into the guide hole 47 of the nozzle needle 6, which has a step 48 and which The step 48 is used as a control lip, so that in the open position of the nozzle needle 6 the opening 45 is freed from the step 48 and in the closed position the opening 45 is freed by a shaft section 49 of large diameter.
The composite nozzle according to any one of claims 1 to 5, characterized in that the composite nozzle is configured to hermetically seal. 7. Claims characterized in that the opening 66 of the supply conduit 67 provided for the further additional component is arranged in the region of the sealing seat 12 in the needle sleeve 5 with the housing bore 4 The composite nozzle according to any one of Items 1 to 6. 8 Forming tool 5 via abutting guides 57, 58 and corresponding connecting elements 55, 56, 59, 60
1. A composite nozzle according to any one of claims 1 to 7, characterized in that the composite nozzle is combined with a composite nozzle according to any one of claims 1 to 7. 9 A stability chamber 61 located in front of the mold hollow chamber 54 is provided within the surrounding wall of the forming tool 51, and the inlet opening 65 of the stability chamber 61 matches the outlet opening 18 of the nozzle at the connection position of the composite nozzle. 9. A composite nozzle as claimed in claim 8, characterized in that it is closed by a closing slide (62) which is integrated into the surrounding wall of the forming tool (51). 10. A process for guiding the merging of at least two fluid reaction components for the production of plastics, in particular foam plastics, with the aim of initiating the reaction by mixing, in which case the reaction components are metered, In a type in which one reaction component is concentrically guided in the center and one or more other reaction components surround the first reaction component, a central jet is used for the merging guidance. and one or more concentric jets. 11. A method according to claim 10, characterized in that high relative velocities are produced such that turbulence is formed in the boundary layer between each jet. 12. Claim 1, characterized in that when more than two jets are generated, these other jets are supplied or interrupted at any time.
The method according to item 0 or item 11.