WO2018019326A1

WO2018019326A1 - Injection moulding device and injection moulding method

Info

Publication number: WO2018019326A1
Application number: PCT/DE2017/100588
Authority: WO
Inventors: Michael LAMM; Gerhard Vollmer; Volker Lang
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2016-07-26
Filing date: 2017-07-17
Publication date: 2018-02-01
Also published as: DE112017003748A5; DE102016213631A1

Abstract

The present invention relates to an injection moulding device (10) for producing a component, having an injecting unit (12) for supplying a flowable raw material and having an injection mould (14) for shaping the raw material, wherein the injecting unit (12) has at least one injection channel (16) for injecting the raw material into the injection mould (14), wherein the injection channel (16) is heatable by a temperature control element (18) for controlling the temperature of the raw material located in the injection channel (16), and wherein the injecting unit (12) can be brought into contact with the injection mould (14) for transfer of the raw material out of the injection channel (16) into the injection mould (14), wherein at least one closure element (22) is provided for closing the injection channel (16) at an injection opening (20) for transferring the raw material from the injection channel (16) into the injection mould (14), wherein, during closing of the injection channel (16), the closure element (22) can be arranged such that it bounds a component contour (24) of the injection mould (14). An injection moulding device of this type permits an injection moulding process without a sprue.

Description

Injection molding and injection molding

The present invention relates to an injection molding apparatus. The present invention further relates to a method for producing a component by means of an injection molding method and the use of such a device and / or such a method for producing a component for a clutch, in particular for producing a clutch slave cylinder.

Injection molding is widely used and is used, for example, to make a variety of plastic components. It is common that the corresponding components are made with a gate, such as a screen gate. This is a well-engineered process, but requires the necessary removal of the sprue to make another processing step and also produces a relatively high scrap of raw material.

The document US 8,840,818 describes an injection molding process in which the step of removing a gate is to be avoided. This should be possible as evidenced by this document, that an accurate temperature control of the material used in the injection should be made. This should be allowed to perform the filled mold as a moving member and remove from an injection unit before a sprue hardens on the generated shape. However, such a solution can still offer room for improvement.

It is therefore the object of the present invention, at least partially overcome the known from the prior art disadvantages. It is in particular the object of the present invention to provide a solution by means of which the removal of a sprue can be dispensed with in an injection molding process and / or by which an injection molding process can be easily and inexpensively possible.

The object is achieved by an injection molding apparatus having the features of claim 1 and by an injection molding with the features of claim 9. Preferred embodiments of the invention are described in the subclaims, in the description or the figures, wherein further in the subclaims or in The features described or shown in the description or the figures, individually or in any combination, may constitute an object of the invention, unless the context clearly indicates otherwise.

It is proposed an injection molding apparatus for producing a component, comprising an injection unit for providing a flowable raw material and an injection molding tool for molding the raw material, wherein the injection unit has at least one injection channel for injecting the raw material into the injection mold, which by a tempering for tempering the injection unit in the injection channel is heated, and wherein the injection unit is brought into contact with the injection mold for transferring the raw material from the injection channel into the injection mold, wherein at least one closure element is provided which the injection channel at an injection port for transferring the raw material of can close the injection channel in the injection mold, wherein the closure element can be arranged at a closing of the injection channel such that it has a component contour of the injection mold b e-borders.

A prescribed injection molding apparatus allows the production of high quality components with a low production cost in a simple manner. The above-described injection molding apparatus comprises an injection unit which serves to provide a flowable raw material. For example, the raw material, such as a plastic, can be filled into the injection unit, heated there and in be provided liquid form. Alternatively, the raw material can also be filled directly in the liquid state into the injection unit and further heated there.

Furthermore, the injection molding apparatus comprises an injection mold in which the liquid, in particular molten, raw material supplied from the injection unit is formed, whereby the component is formed. In the injection mold, the raw material can harden and thus form the component. The injection unit has at least one injection channel, from which the raw material is transferred into the injection mold through an injection opening of the injection channel, which can also be referred to as a hot runner nozzle. In order to temper the raw material and thus to keep it in a liquid state, a tempering element is furthermore provided which acts on the injection channel or on the raw material located in the injection channel.

Furthermore, it is provided that the injection unit can be brought into contact with the injection mold for transferring the raw material from the injection channel into the injection mold. Thus, as close as possible a connection between the injection channel or the injection opening and the injection mold should be formed.

In the case of the above-described injection molding apparatus, it is further provided that a closure element, in particular as part of the injection molding apparatus, is preferably provided as part of the injection unit, which can close off the injection channel at the injection opening. In this case, when the injection channel is closed, the closure element can be arranged in such a way that it delimits a component contour of the injection mold. In particular, this embodiment allows an improved injection molding process, as described below.

Because through the closure element, the injection opening can be released in a transfer of the raw material and can be closed after transferring the raw material, the injection opening. In this case, the injection opening can be closed in such a way that the closure element is closed when closing the inlet. injection channel can be arranged such that it limits a component contour of the injection mold. This should mean, in particular, that a component contour of the injection molding tool substantially reproduces or corresponds to the shape of the component to be produced. The component contour can thus be at least partially defined by the injection molding tool. When the injection channel is closed by the closure element, however, it is provided that the closure element delimits the component contour or a part thereof and thus, in other words, forms a part of the boundary of the component contour by the position of the closure element. This allows that, for example, after hardening of the raw material in the injection mold, the injection unit can be removed together with the closure element of the injection mold or vice versa, whereby at the junction of the component contour to the injection channel, the resulting component in its desired shape and thus in particular without sprue on Component arises.

In other words, the above-described injection molding device allows the sprue to be formed directly in the injection channel or to be integrated into it, if the material cools there. This allows the component to continue to be molded over an annular surface, but without the formation of a sprue on the component. As a result, the component can be produced as a tool and without separate processing.

Thus, the subsequent removal of the sprue can be dispensed with, which makes a process step in the manufacture of the component by means of injection molding obsolete. This allows a relatively easy to produce process in which the production rate can be increased and can be performed on devices for removing the sprue.

Moreover, in an injection molding process which is compulsory in the prior art by forcibly producing the gate, the broke can be prevented particularly when no sprue is formed in the injection passage but the raw material is further kept in a liquid state and used further can be. This allows a significant saving in raw material, which can save resources and reduce costs.

The surface of the component which arises adjacent to the closure element can already have a sufficient quality, so that post-treatment processes can be dispensed with.

Furthermore, an above-described injection molding apparatus enables advantages of using a screen gate to be equally satisfied. For a Schirmanguss has traditionally has the advantage that in the component produced weld lines can be prevented by injection points. This is advantageous since each weld line can form a mechanical weakening of the component and a possible break point in the bursting pressure test or in later use. Such weld lines can also be prevented using the above-described injection molding apparatus.

Another advantage of closing the injection opening can be seen in the fact that the raw material located in the Eispritzkanal can be easily kept liquid and thus particularly easy to continue to use.

It can preferably be provided that the closure element is designed as a displaceable sleeve which is displaceable between a position closing the injection opening and a position releasing the injection opening. In this case, the sleeve can be arranged inside or outside the injection channel and can run approximately parallel to it. In particular, in this embodiment, a space-saving and particularly simple embodiment can be made possible, the implementation is also possible without significant modifications. This enables a cost-saving implementation of the present invention. It may be preferred that the sleeve, as well as basically any other closure element, is pneumatically or hydraulically displaceable. In this embodiment, in turn, a cost-effective implementation is possible. Furthermore can be a hydraulically or pneumatically controlled displacement of the closure element allow a well-defined displacement, which can further increase the quality of the component to be produced. It may further be preferred that an injection opening is arranged axially relative to the injection channel, that this is thus arranged in particular in an axial plane and the raw material leaves the injection channel in the radial direction. In this arrangement, the provision of a closure element is particularly easy, since, for example, using a displaceable sleeve, this can be closed at a parallel to the axis of the injection channel displacement, as described above, the injection opening in a simple manner. In addition, using a valve disk, which may have the injection openings, the injection mold can be filled safely and a relative mobility of the injection mold and injection unit can be easily possible.

Alternatively or additionally, it may be provided that an injection opening is arranged radially with respect to the injection channel, that is, in particular, is aligned in a radially arranged plane, and that a closure element is an axial one

displaceable plug member having a closure portion, wherein the closure portion with the injection channel, such as an inner periphery of the same, the injection port is sealingly brought into contact. In this case, it can be provided, for example, that the plug element is designed conically with a tip arranged on the injection channel side. In this embodiment too, a good relative mobility of injection molding tool and injection unit can be easily possible, which can simplify the construction of the injection molding apparatus. In this case, depending on the shape to be produced or the component contour, an axial injection of the raw material into the injection mold can be advantageous. However, a combination of axial and radial injection opening with corresponding closure elements may also be possible. With regard to the tempering element, it can be provided that the injection channel is arranged coaxially to the tempering element, or that in other words in at least one part of the injection channel, the tempering element is arranged coaxially to the latter. For example, the tempering element can be present within the injection channel, the injection channel thus comprise the tempering element, for example, or can the tempering element be provided outside the injection channel, ie the tempering element at least partially surround the injection channel. This allows a particularly effective tempering, in particular heating, of the raw material, so that the properties of the raw material, for example with respect to the viscosity, during injection into the injection mold can be particularly advantageous.

In a further embodiment, it can be provided that the closure element is formed by a piston located in the injection channel. It may be preferred that the piston is displaceable in such a way to transfer the raw material from the injection channel into the component contour. The piston can then be displaced up to or beyond the injection opening, so that the piston can limit the component contour. For example, a cylindrical main body of the piston can serve as a closure element or a cylindrical base body can have a sleeve-like extension which can serve as a closure element.

In summary, a previously described injection molding device thus allows the production of a wide variety of components with few production steps and in a high quality.

With regard to further advantages and technical features of the injection molding apparatus, reference is made to the following description of the method, the use, the figures and the description of the figures. The subject matter of the present invention is furthermore an injection molding method for producing a component comprising the method steps, in particular using an injection molding device described above: a) providing a liquid raw material in an injection channel of an injection unit, wherein an injection opening of the injection channel can be closed by a closure element;

b) transferring the liquid raw material from the injection channel through the injection opening into an injection mold;

c) closing the injection opening by the closure element such that the closure element delimits a component contour of the injection mold; and d) solidifying the raw material contained in the injection mold, in particular by active or passive cooling.

By such a method, any component can be produced by an injection molding process in a simple manner and with comparatively few process steps. In summary, this can be realized, in particular, by the injection opening being closed by the closure element in such a way that the closure element delimits a component contour of the injection molding tool. As a result, after a subsequent cooling of the component produced, it can be produced without an attachment. The method step of removing the sprue can thus be dispensed with in an advantageous manner.

With regard to further advantages and technical features of the method, reference is made to the description of the injection molding apparatus, the use, the figures and the description of the figures.

The present invention furthermore relates to the use of an injection molding apparatus described above and / or an injection molding method described above for producing a component for a coupling, in particular for producing a clutch slave cylinder.

Even if the above-described device or the method described above is not limited to an application for the production of couplings, In particular, an application in the manufacture of components for clutches, such as for the manufacture of housings for clutch slave cylinder, such as for CSC housing, or clutch master cylinder be advantageous. Thanks to their shape, these components offer good properties for training through an injection molding process.

With regard to further advantages and technical features of the use, reference is made to the description of the injection molding apparatus, the method, the figures and the description of the figures.

In the following, particularly preferred embodiments of the invention will be explained with reference to the accompanying drawings, wherein it is explicitly pointed out that the object according to the invention is not limited to the described embodiments. Show it:

Fig. 1 is a schematic view of a first embodiment of an injection molding apparatus;

FIG. 2 is a schematic view of a second embodiment of an injection molding apparatus; FIG.

3 is a schematic view of a third embodiment of an injection molding apparatus; and

Fig. 4 is a schematic representation of the method according to the invention.

FIG. 1 shows a first embodiment of an injection molding apparatus 10 for producing a component. The injection molding apparatus 10 includes an injection unit 12 for supplying a flowable raw material and an injection molding tool 14 for molding the raw material. The injection unit 12 in this case comprises at least one injection channel 16 for injecting the raw material into the injection mold 14. The injection channel 16 can be heated by a tempering element 18 for tempering the raw material located in the injection channel 16. FIG. 1 further shows that the injection unit 12 is in contact with the injection molding tool 14 for transferring the raw material from the injection channel 16 into the injection molding tool 14. In detail, an injection opening 20 of the injection channel 16 is opened in the injection mold 14.

FIG. 1 further shows that the injection channel 16 has a closure element 22, which can close the injection channel 16 at the injection opening 20 for transferring the raw material from the injection channel 16 into the injection mold 14, the closure element 22 being such when the injection channel 16 is closed can be arranged that it limits a component contour 24 of the injection mold 14. As a result, the closure element 22 directly touches the component contour 24, so that no sprue residues arise, which would later have to be removed by cutting or punching technology. In the figure 1, the component contour 24 is designed as a housing of a clutch slave cylinder.

The closure element 22 is designed as a displaceable sleeve which is displaceable between a position closing the injection opening 20 of the injection channel 16 and a position releasing the injection opening 20 of the injection channel 16, as should be shown by the arrow 26.

FIG. 1 shows an embodiment in which the injection channel 16 is arranged coaxially to the tempering element 18, the tempering element 18 being arranged outside the injection channel 16. In this case, the tempering element 18 can keep the raw material in the injection channel 16 in the liquid state.

Furthermore, it is provided in FIG. 1 that the injection opening 20 is arranged axially with respect to the injection channel 16. This is realized in that a shaft 28 of the injection channel 16 extends coaxially with the injection channel 16 or is partially limited and designed valve disk-shaped at the injection end, so that the raw material is deflected in the radial direction and so radially into the component contour 24, according to FIG the contour of a housing of a designed as a CSC Clutch slave cylinder, passes. Arranged radially opposite the shaft 28, the ice injection channel 16 is bounded by the tempering element 18.

Basically and independently of the specific embodiment, it may be provided that the injection channel 16, which may also be referred to as a melt channel or hot runner, is bounded radially by the temperature control element 18 and / or the closure element 22 and / or the shaft 28, wherein basically each Combination of the aforementioned examples or a radial double-sided limitation of the injection channel 16 by the tempering 18, the closure element 22 or the shaft 28 is possible.

FIG. 2 also shows an embodiment in which the tempering element 18 is likewise arranged coaxially with the injection channel 16, but is arranged radially within the injection channel 16 or surrounded by the injection channel 16.

FIG. 3 shows a further embodiment of an injection molding apparatus 10 or an injection unit 12 for an injection molding apparatus 10. In the embodiment according to FIG. 3, the injection channel 16 is provided within the shank 28, wherein a tempering element 18 is provided radially outside the shank 28. The closure element 22 is an axially displaceable plug element. The closure element 22 or the plug element has a closure region 30 which can be brought into contact with the injection opening 20 with an inner circumference 32 of the injection channel 16 or of the shaft 28 defining the injection channel 16. It can be seen that the plug element is designed conically with a tip 40 arranged on the injection channel side. The closure element 22 or the plug element can be arranged to be displaceable in particular in the axial direction, or can be fixed to a housing component 34 by webs, not shown, such as three webs. In the last embodiment, for example, the shaft 28, which may be designed as a sleeve and, for example, can be displaced hydraulically or pneumatically, the inner circumference 32 against the Press closure area 30. Again, the closure member 22 and optionally the shaft 28 may limit the component contour 24.

In this embodiment, the raw material is transferred axially into the component contour 24, the injection opening 20 is thus aligned radially.

In the figure 4 an injection molding method is described by way of example. In this case, the step I shows a state in which the injection channel 16 is filled through a filling opening 36 with liquid raw material, such as a plastic melt. Step II shows a state in which the stem 28 and a piston 38 located in the injection port 16 for injecting the raw material into the component contour 24 advance toward the injection port 20 until the state of step III is reached at the raw material from the injection port 16 was injected through the injection opening 20 in the component contour 24, wherein the filling opening 36 can be closed by the piston 38 sen. The volume of raw material which is displaced is, for example, the complete metering quantity, including a volume which may possibly be necessary for repressing. In this case, the piston 38 serves as a closure element 22 and closes the injection opening 20 and limits the component contour 24. Subsequently, as shown in step IV, the piston 38 and the shaft 28 are retracted to transfer new raw material into the injection channel 16. The piston 38 releases the filling opening 36 again.

List of accessories Injection molding device

injection unit

injection mold

Injection channel

tempering

Injection port

closure element

component contour

arrow

shaft

closure area

inner circumference

housing component

fill opening

piston

top

Claims

claims

1 . An injection molding apparatus for manufacturing a component, comprising an injection unit (12) for providing a flowable raw material and comprising

Injection molding tool (14) for molding the raw material, wherein the injection unit (12) has at least one injection channel (16) for injecting the raw material into the injection mold (14), wherein the injection channel (16) through a

Temperature control element (18) for controlling the temperature in the injection channel (16) located raw material is heated, and wherein the injection unit (12) with the injection mold (14) for transferring the raw material from the injection channel (16) into the injection mold (14) in contact can be brought, characterized in that at least one closure element (22) is provided for closing the injection channel (16) at an injection port (20) for transferring the raw material from the injection channel (16) in the injection mold (14), wherein the closure element (22) can be arranged at a closing of the injection channel (16) such that it limits a component contour (24) of the injection molding tool (14).

2. Injection molding apparatus according to claim 1, characterized in that the closure element (22) is designed as a displaceable sleeve which is displaceable between a the injection opening (20) closing position and the injection opening (20) releasing position.

3. Injection molding apparatus according to one of claims 1 or 2, characterized in that an injection opening (20) with respect to the injection channel (16) is arranged axially.

4. Injection molding apparatus according to one of claims 1 to 3, characterized in that an injection opening (20) with respect to the injection channel (16) is arranged radially and that a closure element (22) has an axially displaceable

Plug element with a closure region (30), wherein the closure Rich (30) with the injection channel (16) the injection port (20) is sealingly brought into contact.

5. Injection molding apparatus according to claim 4, characterized in that the plug element is formed conically with a injection channel side arranged tip (40).

6. Injection molding apparatus according to one of claims 1 to 5, characterized in that the injection channel (16) is arranged coaxially to the tempering (18).

7. Injection molding apparatus according to one of claims 1 to 6, characterized in that the closure element (22) is formed by a piston located in the injection channel (16).

8. Injection molding apparatus according to one of claims 1 to 7, characterized in that the closure element (22) is pneumatically or hydraulically displaceable.

9. injection molding method for producing a component comprising the method steps: a) providing a liquid raw material in an injection channel (16) of an injection unit (12), wherein an injection port (20) of the injection channel (16) by a closure element (22) is closable; b) transferring the liquid raw material from the injection channel (16) through the injection port (20) into an injection mold (14); c) closing the injection opening (20) through the closure element (22) such that the closure element (22) delimits a component contour (24) of the injection molding tool (14); and d) solidifying the raw material contained in the injection mold (14).

10. Use of an injection molding apparatus (10) according to any one of claims 1 to 8 and / or an injection molding method according to claim 9 for producing a component for a clutch, in particular for producing a clutch slave cylinder.