Mixing device for mixing and processing a mixture and method for operating a mixing device

Abstract

The invention relates to a mixing device (1) for mixing and processing a mixture, comprising a mixing chamber (2) having a first mixing chamber section (3) and a second mixing chamber section (4). The mixing device (1) also comprises an opening hatch (5) which is coupled to the mixing chamber (2) and which is designed to be rotatable about an axis of rotation (R1) such that, in a closed state, the opening hatch (5) constitutes a base section of the mixing chamber (2) and delimits sections of the two mixing chamber sections (3, 4), and, in an open state, the opening hatch releases an opening region of the mixing chamber (2) for the mixture to exit. The mixing device (1) also comprises a cleaning unit having a cleaning device (13), which is designed to clean an associated contact surface (11, 12) of the mixing chamber (2), contacting a corresponding contact surface of the opening hatch (5) in the closed state, as required in the open state of the opening hatch (5).

Description

[0001] 202402847

[0002] - 1 -

[0003] Description

[0004] Mixing device for mixing and processing a mixture and method for operating a mixing device

[0005] The present invention relates to a mixing device for mixing and processing a mixture and a method for operating such a mixing device.

[0006] Vehicles have tires, which typically consist of a rubber component in the form of a rubber tire tread. In the manufacture of tires or other rubber components, a production method that enables cost-effective and reliable manufacturing of the respective product is always desirable.

[0007] The invention aims to provide a mixing device and a method for operating a mixing device, each of which can contribute to the cost-effective and reliable production of a tire.

[0008] The problem is solved by the respective features of the independent patent claims. Advantageous further developments are specified in the respective dependent patent claims.

[0009] According to one aspect of the invention, a mixing device for mixing and processing a mixture comprises a mixing chamber with a first mixing chamber section and a second mixing chamber section, which are in particular implemented as mixing chamber halves. The mixing device further comprises a hinged saddle which is coupled to the mixing chamber and which is rotatable about a pivot axis, so that the hinged saddle can be moved between a closed state and an open state. In the closed state, the hinged saddle forms a bottom section of the mixing chamber and sectionally delimits the two mixing chamber sections. By rotating the hinged saddle about the pivot axis, the mixing chamber is opened and the open state of the hinged saddle is formed, in which an opening area of ​​the mixing chamber is released for the exit of the mixture. The mixing device also comprises a 202402847

[0010] - 2 -

[0011] Cleaning unit with at least one cleaning device designed to clean, as required, an associated contact surface of the mixing chamber, which in the closed state contacts a corresponding contact surface of the folding saddle, when the folding saddle is open.

[0012] The described device can contribute to an improved processing of a mixture, particularly in the case of a tire or rubber compound for a rubber component. This can lead to a cost-effective and reliable tire manufacturing process for motor vehicles. The cleaning unit enables automated cleaning, eliminating the need for time-consuming and expensive manual cleaning.

[0013] The mixing device is typically designed as a cylindrical vessel, with the contact surfaces predominantly extending as elongated strips along the central axis of the cylindrical vessel. Specifically, two opposing contact surfaces are present, which interact with corresponding contact surfaces of the hinged saddle. In the closed state, the respective contact surfaces make contact at least partially, or in such a way that the interior of the mixing device is sealed against the escape of the mixture being processed. The mixing device can be designed as an internal mixer of a mixing system and enable reliable cleaning in the hinged saddle area.

[0014] According to a further development of the mixing device, the cleaning unit has two or more cleaning devices, each of which is designed to clean an associated contact surface of the mixing chamber as needed, when it is accessible for cleaning.

[0015] According to a further development of the mixing device, each cleaning device comprises a nozzle designed to spray a specified medium at high pressure onto the associated contact surface of the mixing chamber for cleaning purposes. The medium can be, in particular, a high-pressure water jet and / or a jet of dry ice. Alternatively, 202402847

[0016] - 3 - or additionally, further materials or mixtures of substances may be provided for cleaning, which can be automatically applied to the contact surface to be cleaned by the cleaning device. The respective medium should, in particular, not have any adverse effect on the dispensed mixture or the mixture to be processed subsequently.

[0017] According to a further development, the mixing device has a sensor designed to monitor a specific contact surface of the mixing chamber and to capture a measurement signal containing information about contamination of that contact surface. Such a sensor can be implemented as an optical sensor, in particular as a video camera.

[0018] According to a further development, the mixing device has a locking lever designed to secure the folding saddle in the closed position. The locking lever can be rotatably mounted about a predetermined axis of rotation, so that after the folding saddle has been pivoted into the closed position, it rotates and contacts and supports the folding saddle from below. The locking lever can be designed as a toggle lever.

[0019] According to a further aspect of the invention, a method for operating an embodiment of the previously described mixing device comprises mixing a predetermined mixture in the mixing chamber sections of the mixing chamber. The mixture can, in particular, be a rubber mixture for tire manufacturing. The method further comprises opening the mixing chamber by rotating the hinged saddle about the axis of rotation, thereby releasing the opening area of ​​the mixing chamber for the mixture to exit. The method further comprises cleaning the respective contact surface of the mixing chamber by means of a respective cleaning device of the cleaning unit after the mixture has exited the mixing chamber.

[0020] The process can be carried out after the release of a processed mixture and / or before the processing of a mixture. In particular, it is 202402847

[0021] - 4 - useful to carry out the procedure after a processed mixture has left the mixing device and any residues may remain on one or more contact surfaces.

[0022] The process can be further developed such that the respective contact surface is cleaned using the respective cleaning device after each opening of the mixing chamber. This ensures that the respective contact surfaces are kept as clean as possible.

[0023] Alternatively or additionally, the method can be configured to include closing the folding saddle and detecting its closed state. Cleaning the respective contact surface using the cleaning device is then preferably carried out depending on the detected closed state of the folding saddle. This allows, for example, the determination that a closing operation was successful and no cleaning is necessary. If it is determined that a closing operation was unsuccessful, cleaning of the contact surfaces can be initiated. A subsequent closing operation should then be successful, provided the failure was due to contamination of the cleaned contact surfaces.

[0024] According to a further development, the method involves capturing a measurement signal using a sensor, particularly in the form of a video or photo camera. This measurement signal contains information about contamination of a particular contact surface, and the cleaning of that contact surface using the appropriate cleaning device is carried out based on the sensor's captured measurement signal. For example, if camera images indicate contamination on one or more contact surfaces, cleaning can be initiated automatically. Alternatively or additionally, cleaning of the respective contact surface can be initiated manually if an operator of the machine detects contamination based on the captured video or photo signal. 202402847

[0025] - 5 -

[0026] It is a finding related to the present invention that, after the end of a mixing process, particularly in the hinged saddle area, contaminants can remain that are currently difficult to remove. After the end of a mixing process in an internal mixer, the hinged saddle is opened and the mixing chamber empties. The hinged saddle comprises a saddle roof that is mounted on a saddle support. The saddle support is attached to a pivot axis and can be locked in the closed position by a toggle lever. To open, the toggle lever is folded down and the saddle support is rotated 180° by a pivot drive, thus releasing the opening area of ​​the internal mixer.

[0027] Especially with sticky mixtures, mixture particles often adhere to the opening area of ​​the hinged saddle, particularly in the contact areas with the mixing chamber halves. These adhesions or bonds can negatively impact further processing and, for example, become trapped between the hinged saddle and the chamber wall when closing the mixing chamber, preventing the saddle from closing and locking completely. With conventional systems, cleaning then requires, for example, putting the mixer into maintenance mode, and having a worker wearing protective clothing and respiratory protection enter a shaft below the hinged saddle and scrape off the adhesions with a spatula.

[0028] The previously described adverse effects can be counteracted by means of the mixing device and the corresponding cleaning process. Deposits can be removed using a pressure-accelerated medium, for example, a high-pressure water jet or a dry ice jet. The corresponding nozzles of the respective cleaning device are preferably positioned and aligned opposite the surface to be cleaned. The cleaning sequences can be performed either after each opening of the folding saddle and / or specifically after an unsuccessful closing attempt. The area of ​​the folding saddle can be monitored with a camera, and a cleaning process can then be triggered by an operator when they observe the build-up of deposits. 202402847

[0029] - 6 -

[0030] This type of cleaning, using the mixing device and cleaning process, can be retrofitted to any existing mixer at low cost and can subsequently contribute to an improved processing of the mixtures. The mixer no longer needs to be stopped, and no person has to laboriously climb into a shaft and scrape off deposits with a spatula.

[0031] The following are exemplary embodiments of the invention explained with reference to schematic drawings. These show:

[0032] Figure 1 shows a schematic embodiment of a

[0033] Mixing device for processing a mixture,

[0034] Figure 2 shows a schematic embodiment of a

[0035] Folding saddle area of ​​the mixing device according to Figure 1, and

[0036] Figure 3 shows a flowchart for a procedure for operating the

[0037] Mixing device.

[0038] Figure 1 schematically shows an embodiment of a mixing device 1 for mixing and processing a mixture, for example a rubber mixture for tire manufacturing. The mixing device 1 has a mixing chamber 2 with a first mixing chamber section 3 and a second mixing chamber section 4, which, in a typically symmetrical design, can also be referred to as mixing chamber halves.

[0039] The mixing device 1 further comprises a folding saddle 5, which is coupled to the mixing chamber 2 and is rotatable about a pivot axis R1. The folding saddle 5 can thus be moved between a closed and an open state. In the closed state, the folding saddle 5 forms a bottom section of the mixing chamber 2 and delimits a respective section of the two mixing chamber halves 3 and 4. In the open state, a 202402847

[0040] - 7 -

[0041] The opening area of ​​mixing chamber 2 is now open for the mixture to escape. In Figures 1 and 2, the direction of opening is indicated by arrow symbols.

[0042] The folding saddle 5 comprises a saddle roof 6 facing the mixing chamber halves 3, 4, and a saddle support 7 that carries the saddle roof 6 and is coupled to the axis of rotation R1. The saddle roof 6 has a raised central area and is essentially shaped such that it continues an inner contour of the respective mixing chamber half 3, 4. Mixing rotors are typically arranged in the mixing chamber halves 3, 4, which circulate the mixture. Accordingly, the mixing chamber halves 3, 4 are essentially cylindrical and have an overlapping area in projections.

[0043] The mixing device 1 also includes a cleaning unit with two cleaning devices 13, which are designed, for example, as nozzles that can emit a high-pressure water jet when activated. The cleaning devices 13 are configured to clean a respective contact surface 11, 12 of the mixing chamber 2 as needed. Accordingly, the cleaning devices 13 are preferably arranged opposite their respective contact surfaces 11, 12 of the mixing chamber 2 (see Figure 2). The contact surfaces 11, 12 of the mixing chamber 2 interact with associated contact sections of the pitched roof 6 to reliably seal the interior or the two halves 3, 4 of the mixing device 2.

[0044] Furthermore, the mixing device 1 can have a locking lever 8, which is provided for locking and securing the closed state of the folding saddle 5. The locking lever 8 is designed as a toggle lever and is rotatable about a pivot axis R2. To secure the folding saddle 5, it is pivoted towards it and supports it from below in the closed state. To open the mixing device 1, the locking lever 8 is pivoted away from the folding saddle 5, and the folding saddle 5 can be folded downwards in the direction of the arrow about the pivot axis R1. Figure 2 accordingly shows a transition state in which the locking lever 8 is already removed from the folding saddle 5, but the folding saddle 5 is closed. The locking and forming of the 202402847

[0045] - 8 - closed and locked state or the pivoting of the folding saddle 5 and forming the open position.

[0046] Furthermore, the mixing device 1 can include a cooling system with coolant lines that can provide a predetermined cooling during mixing. Figure 2 illustrates a coolant line 9 that is arranged in the area of ​​the saddle support 7 and can provide a coolant supply in the area of ​​the saddle roof 6 and / or in edge sections that delimit the respective mixing chamber halves 3, 4.

[0047] After a mixing process, contaminants may remain in the hinged saddle area, which must be removed before further processing of the mixtures. Such contaminants, in the form of adhesions, may remain, particularly after emptying, on the edges or contact surfaces 11, 12 surrounding the opening area. Especially with sticky mixtures, adhesion of mixture particles may occur in the area of ​​the contact surfaces 11, 12. Such adhesions can adversely affect subsequent processing and, for example, prevent the hinged saddle 5 from closing and locking completely.

[0048] The described mixing device 1 enables a low-effort and automated cleaning process, allowing for timely subsequent mixing and thus saving time and costs. Adhesions can be removed using a pressure-accelerated medium, such as a high-pressure water jet or a dry ice jet. The corresponding nozzles of the respective cleaning device 13 are pre-positioned and aligned to ensure reliable cleaning of the associated contact surfaces 11 and 12 (see Figure 2).

[0049] A flowchart for a method for operating and cleaning the mixing device 1 can be carried out as follows, according to Figure 3.

[0050] In step S1, a predetermined mixture is introduced into mixing chamber 2 and mixed in mixing chamber sections 3 and 4. 202402847

[0051] - 9 -

[0052] In step S2, the mixing chamber 2 is opened by rotating the hinged saddle 5 around the axis of rotation R1. Once the opening area of ​​the mixing chamber 2 is cleared, the processed mixture can exit downwards from the mixing chamber 2.

[0053] In step S3, the contact surfaces 11, 12 of the mixing chamber 2 are cleaned using the associated cleaning devices 13. Such a cleaning process can be carried out after each opening of the folding saddle and / or specifically after an unsuccessful attempt to close the folding saddle 5. The area of ​​the folding saddle

[0054] 5 can be monitored with a camera and a cleaning process according to step S3 can be carried out automatically and / or triggered by an operator if it is detected that an adhesion is present in the area of ​​the contact surfaces 11 , 12.

[0055] 202402847

[0056] - 10 -

[0057] Reference symbol list

[0058] 1 Mixing device

[0059] 2 Mixing chamber 3 First mixing chamber section

[0060] 4 second mixing chamber section

[0061] 5 folding saddles

[0062] 6 Gable roof

[0063] 7 Saddle carrier 8 Locking lever

[0064] 9 Coolant line

[0065] 11 first contact surface

[0066] 12 second contact surface

[0067] 13 Cleaning device

[0068] R1 pivot axis of the folding saddle

[0069] R2 Pivot axis of the locking lever

[0070] S(i) Steps of a method for operating a mixing device

Claims

202402847 - 11 - Patent claims 1. Mixing device (1 ) for mixing and processing a mixture, comprising: - a mixing chamber (2) with a first mixing chamber section (3) and a second mixing chamber section (4), - a hinged saddle (5) coupled to the mixing chamber (2) and designed to be rotatable about a pivot axis (R1), such that in a closed state the hinged saddle (5) establishes a bottom section of the mixing chamber (2) and sectionally limits the two mixing chamber sections (3, 4), and in an open state releases an opening area of ​​the mixing chamber (2) for the mixture to escape, and - a cleaning unit with a cleaning device (13) which is designed to clean, as required, a contact surface (11 , 12) of the mixing chamber (2), which in the closed state contacts a corresponding contact surface of the folding saddle (5), in the open state of the folding saddle (5).

2. Mixing device (1) according to claim 1, wherein the cleaning unit comprises two or more cleaning devices (13), each of which is configured to clean an associated contact surface (11, 12) of the mixing chamber (2), which contacts a corresponding contact surface of the folding saddle (5) in the closed state, as required in the open state of the folding saddle (5).

3. Mixing device (1) according to one of the preceding claims, wherein the respective cleaning device (13) comprises a nozzle designed to spray a predetermined medium under pressure acceleration onto the associated contact surface (11, 12) of the mixing chamber (2).

4. Mixing device (1) according to claim 3, wherein the medium is realized as a high-pressure water jet and / or as a jet of dry ice.

5. Mixing device (1) according to one of the preceding claims, comprising: 202402847 - 12 - a sensor configured to monitor a respective contact surface (11 , 12) of the mixing chamber (2) and to capture a measurement signal that includes information about contamination of the respective contact surface (11 , 12).

6. Mixing device (1) according to claim 5, wherein the sensor is implemented as a video camera.

7. Mixing device (1) according to one of the preceding claims, comprising: a locking lever (8) designed to secure the folding saddle (5) in the closed state.

8. Method for operating a mixing device (1) according to any one of the preceding claims, comprising: - Mixing a predetermined mixture in the mixing chamber sections (3, 4) of the mixing chamber (2), - Opening the mixing chamber (2) by rotating the hinged saddle (5) about the axis of rotation (R1) and thereby releasing the opening area of ​​the mixing chamber (2) for the mixture to escape, and - Cleaning of the respective contact surface (11 , 12) of the mixing chamber (2) by means of a respective cleaning device (13) of the cleaning unit after the mixture has exited the mixing chamber (2).

9. Method according to claim 8, wherein the cleaning of the respective contact surface (11, 12) by means of the respective cleaning device (13) is carried out after each opening of the mixing chamber (2).

10. The method of claim 8 or 9, comprising: - Closing the folding saddle (5) and detecting a closed state of the folding saddle (5), and - Cleaning the respective contact surface (11 , 12) using the respective cleaning device (13) depending on the detected closing state of the folding saddle (5). 202402847 - 13 - 11. Method according to any one of claims 8 to 10, comprising: - Acquiring a measurement signal by means of a sensor that includes information about contamination of a respective contact surface (11, 12), and - Cleaning the respective contact surface (11 , 12) using the respective cleaning device (13) depending on the detected measurement signal of the sensor.

12. Method according to claim 11, wherein the sensor is designed as a video camera and captures a video signal which includes information about contamination of a respective contact surface (11, 12), wherein the cleaning of the respective contact surface (11, 12) by means of the respective cleaning device (13) is initiated automatically and / or manually depending on the captured video signal of the video camera.

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