Suction mechanism for milled material, scabbling device and related suction for milled material and corresponding method

Abstract

The invention relates to a movable suction device for milling material, comprising: at least one compartment (50); a suction loading mechanism (60) at the input end of the compartment, the suction loading mechanism being arranged to depressurize the compartment (50) relative to the external environment and configured to load the milling material into the compartment by suction resulting from such depressurization; a discharge mechanism (65) at the output of the compartment (50), the discharge mechanism being configured to discharge the milled material from the compartment (50), characterized in that the suction device comprises: a detection mechanism (58) configured to detect the presence of a milled material shield (75) between the suction loading mechanism (60) and the discharge mechanism (65); and a control mechanism (55) operably connected to the detection mechanism (58) to enable activation of the discharge mechanism (65) when the detection mechanism detects the presence of the milled material shield (75) during operation of the suction loading mechanism (60).

Description

Technical Field

[0001] This invention relates to suction mechanisms, scarification equipment, and related methods for suctioning milled material. The invention is particularly suitable for removing milled material generated during scarification in the construction and infrastructure sectors, as described below. Specifically, the invention aims to continuously remove milled concrete material generated during scarification. Background Technology

[0002] In the construction and infrastructure sectors, special roughening processes are frequently required, which are understood as precise material removal. Roughening can have a variety of reasons. For example, it's used for restoring cultural relics, where a portion of concrete or mortar is removed to replace it with a new layer. The surface to be restored can be of any type, such as the curved arch of a highway tunnel, the curb of an overpass, or the flat wall of a retaining wall.

[0003] Precise roughening of highway tunnel arches is particularly problematic for a variety of reasons, including the curved shape, the possibility of milling material falling onto the operating machinery, and the possibility of excavating toxic materials such as asbestos.

[0004] The applicant has developed a very versatile operating machine and related shaving equipment that can ensure a high degree of shaving precision. This has been the subject of several patent applications, some of which have not yet been published, such as Italian patent application number 102021000007049 and international application numbers PCT / IB2022 / 062198, PCT / IB2022 / 060185, and PCT / IB2022 / 062199.

[0005] The overall layout of this machine includes a bracket on which an articulated arm is mounted, with a milling cutter placed at the distal end of the articulated arm.

[0006] To roughen the tunnel vault, the excavated material needs to be pumped away to prevent the aforementioned problems.

[0007] The applicant has also designed a suction hood that is particularly suitable for his machine, which is protected by unpublished Italian patent application 102023000011181.

[0008] The applicant’s prior patents are mentioned herein by way of incorporation.

[0009] All these parts previously designed by the applicant constitute a fully functional chipping machine, but its efficiency is hampered by the lack of a suction mechanism to connect the generated milled material to the hood that can separate the milled material from the workplace.

[0010] To date, the most common solution is to use various trucks equipped with sealed container suction systems, such as those described in 102006901476112 and EP1714830B1.

[0011] However, these trucks cannot discharge the product while pumping, so at least two trucks are needed to alternate between pumping and discharging the pumped material.

[0012] This means the milling machine must be stopped to connect and disconnect it from various trucks, resulting in prolonged downtime. Even if it were possible to discharge directly to trucks connected to the milling machine without disconnecting it, patent EP1714830B1 suggests tilting the machine, but this is impossible, for example, in tunnels, which are the environment where the applicant's machine is primarily operated and specifically used. Furthermore, in this case, suction must also be interrupted, thus requiring the milling machine to stop operating.

[0013] The problem is exacerbated if the final disposal location of the milled material is far from the roughening location, because in this case, a large number of trucks may need to be on site to avoid wasting travel time, thus unreasonably increasing costs.

[0014] The first attempt to solve this problem can be found in FR3011208A1. Some embodiments of this French patent propose a truck with a body divided into two compartments, one for suction and the other for discharge. The waiting time is limited to the time required to transfer material from the suction compartment to the discharge compartment, because suction must be interrupted during such an operation, as the sealing effect that makes suction possible is lost.

[0015] The French patent then proposes an implementation in which suction is alternately transferred from one compartment to another, thus reversing their functions, and suction can be performed in one compartment while discharge is performed in the other. This allows the scabbing machine to operate uninterruptedly. However, the system in this French patent is very complex and therefore unsuitable for handling basic materials such as milled concrete, as it requires constant switching between two compartments for suction, which occupy half of the machine's total volume. Furthermore, it is an expensive system and is difficult to maintain.

[0016] EP0904978 is also known in the patent literature, which teaches how to manufacture a compartmentalized box, each compartment containing a loading and unloading system. However, this system is not suitable for simultaneously pumping in and out milled concrete material, as it would cause deviation of the airtight compartments. In fact, the loading and unloading system of EP0904978 operates at different times and always requires a connection window to the external environment (see paragraph

[0017] ).

[0017] Therefore, there is a potential need in the art for a suction system for milling concrete material, which is connected to the applicant's shaving machine or other operating machinery capable of eliminating downtime due to waiting for the discharge of suctioned material, especially in working environments within tunnels.

[0018] One object of the present invention is to overcome all or part of the disadvantages of the prior art.

[0019] A preferred object of the present invention is to allow milled material to be simultaneously drawn in and discharged in the same airtight compartment.

[0020] Another object of the present invention is to enable the operating machine to operate continuously by allowing the milling material generated by the operating machine to be continuously sucked away.

[0021] Another object of the present invention is to enable the aforementioned continuous operation, particularly for scabbing machines placed inside tunnels.

[0022] Another object of the present invention is to enable simple and cost-effective management of the removal of milled material from the workplace. Summary of the Invention

[0023] The above-mentioned objective is achieved by the invention as defined in the appended claims.

[0024] According to a first general aspect of the present invention, the present invention relates to a suction device for milling materials, the suction device comprising:

[0025] - At least one compartment (50);

[0026] - A suction loading mechanism (60) located at the input end of the compartment is configured to depressurize the compartment (50) relative to the external environment and is configured to feed the milled material into the compartment by suction generated by such depressurization;

[0027] - A discharge mechanism (65) located at the output end of the compartment (50) is configured to discharge the milled material from the compartment (50).

[0028] The suction device is characterized in that it comprises:

[0029] - A detection mechanism (58) configured to detect the presence of a milled material shielding layer (75) between the suction loading mechanism (60) and the discharge mechanism (65);

[0030] - A control mechanism (55), operably connected to the detection mechanism (58), to enable the discharge mechanism (65) when the detection mechanism detects the presence of the milled material shielding layer (75) during operation of the suction loading mechanism (60).

[0031] According to a second general aspect of the invention, the invention relates to an apparatus for chiseling and suctioning of associated milled material, characterized in that the apparatus comprises at least one suction device of the type described above and at least one chiseling machine (1), the chiseling machine comprising at least one chiseling tool (20) and a suction shroud (100) coupled to the tool, wherein the device and the machine are configured to move at least horizontally relative to the ground (e.g., on a road, railway, etc.), and are operably connected to each other via at least one suction conduit 4, the suction conduit 4 being located between the suction shroud and the inlet suction mechanism (65).

[0032] According to a third general aspect of the present invention, the present invention relates to a method for chiseling and suctioning the milled material produced by said chiseling, characterized by the following steps:

[0033] - During the burring operation, milled material is continuously generated through burring;

[0034] - Provide at least one compartment for receiving the milled material;

[0035] - The milling material is loaded into the suction compartment by an inlet suction loading mechanism (60), which depressurizes the compartment relative to the external environment, wherein the depressurization occurs during the chiseling operation;

[0036] - A discharge mechanism (65) is provided for discharging the milled material from the compartment;

[0037] - Detect the presence of a milled material shielding layer (75) in the compartment between the suction loading mechanism (60) and the discharge mechanism (65);

[0038] - When the presence of the shielding layer (75) is detected, the milling material is discharged from the compartment by operating the discharge mechanism (65), and the milling material is continuously drawn in by the suction loading mechanism (60) during the discharge, thereby generating the milling material for simultaneous discharge and loading during the chiseling operation. Attached Figure Description

[0039] Other features and advantages of the invention will become clearer from the following detailed description of some preferred embodiments of the invention, provided with reference to the accompanying drawings and through indicative and non-limiting examples. In such drawings:

[0040] - Figure 1 A chipping and suction device for relevant milled materials according to the present invention is shown;

[0041] - Figure 2 It shows Figure 1 A longitudinal section of the container in an empty state;

[0042] - Figure 3 This shows the inlet suction configuration when the basic sealing volume of the milled material is achieved. Figure 2 Container;

[0043] - Figure 4 It shows Figure 3 The container is configured to initiate the discharge of milled material at the inlet simultaneously with suction due to the milled material reaching the basic sealing amount;

[0044] - Figure 5 and Figure 6 A corresponding alternative implementation of the container moving mechanism in the previous figure is shown;

[0045] - Figure 7 The image shows a chisel tool with a suction shield applied, as well as... Figure 1 As shown. Detailed Implementation

[0046] refer to Figure 1 The figure shows a burring and suction device according to the invention for milling relevant materials (preferably concrete, asphalt, etc.), which is generally indicated by reference numeral 3 and is also referred to as "the device" below.

[0047] In the following text, vertical and horizontal generally refer to conventional directions relative to the ground.

[0048] The device 3 includes a chiseling machine 1 and a suction device 2. The chiseling machine 1 is preferably configured to chisel concrete, asphalt or the like, and the suction device 2 is configured to suck away the milled material generated by the chiseling machine 1 during operation.

[0049] The chiseling machine 1 and the suction device 2 are movable; for example, they are configured to move horizontally at least on the road surface and are operatively connected to each other via at least one suction conduit 4. For example, they are two operating vehicles, both motor vehicles, or one vehicle towing the other, or they may be a single vehicle.

[0050] The suction catheter 4 is preferably deformable, for example, of a flexible type.

[0051] The shaving machine 1 is essentially a vehicle with a base 5 that is movable relative to the ground. A bracket 10 is preferably rotatably mounted on the base 5 about a vertical axis X. The bracket 10 supports the operating arm 15 and the shaving tool 20 located at the distal end of the arm and drives them to rotate together with it.

[0052] The operating arm 15 is rotatable relative to the bracket about the horizontal axis Y'. In particular, the arm 15 is rotatable in the vertical plane at least between a lowered operating position and an raised operating position.

[0053] The chiseling tool 20 is preferably connected to the distal end of the operating arm 15 in a manner that allows it to rotate about the horizontal adjustment axis Y''.

[0054] This allows for trajectory adjustments when the tunnel vault, which deviates from the arc, must be roughened or when the axis Y' is not located at the center of the vault.

[0055] In connection with or as a replacement for the existence of the rotation axis Y'', a telescopic manipulator 15 may be used.

[0056] refer to Figure 7 The burring tool 20 includes a frame 30 and a milling cutter 40, which is supported by the frame and is in a position rotatable about the milling cutter axis Y'''. The milling cutter axis has at least one horizontal orientation, and preferably can be oriented in several other orientations.

[0057] The roughening tool includes a suction shroud 100, which includes a body 101 configured to partially surround a milling cutter and define an opening 110 through which the milling cutter 40 is exposed to the surface to be roughened. The opening 110 defines a milling and suction area 112 in front of it.

[0058] The cover 100 includes an outlet 125, which is connected to or can be connected to a suction catheter 4 via a connector 140.

[0059] The suction device 2 is a mobile vehicle relative to the ground, comprising a blow-off container 50, such as a large barrel, which can be selectively connected to the outside via a suction loading mechanism 60 and an outlet discharge mechanism 65. Figures 2 to 4 (See it better in the middle).

[0060] The suction loading mechanism 60 is connected to the conduit 4 to suction the milled material produced by the chisel tool 20 through the conduit 4 and the cover 100.

[0061] The device 2 includes a control mechanism 55 for an outlet discharge mechanism 65, which includes at least one memory storing at least one program configured to coordinate the activation of the outlet discharge mechanism 65 with the amount of milled material contained in the container 50 while the inlet suction mechanism is operating, so that the operation of the inlet suction mechanism does not have to be interrupted.

[0062] The control mechanism 55 includes a detection mechanism 58 configured to detect the presence of a milled material shielding layer 75 formed by accumulation between the suction mechanism and the discharge mechanism 65. The detection mechanism preferably includes a mechanism 58 for quantifying the amount of milled material, such as at least one of a weight sensor mechanism, a height sensor mechanism, and a volume sensor mechanism. For example, the height sensor mechanism 58 is placed within the container 50 at a height H corresponding to the amount Q.

[0063] The control mechanism 55 is configured to determine whether the milling material trigger amount Q has been reached. This milling material trigger amount is also referred to below as the shielding amount or the separation amount of the operating effect of the suction loading mechanism 60 and the operating effect of the discharge mechanism 65, which will be clarified below.

[0064] The suction loading mechanism 60 includes at least one pressure-reducing assembly 61 configured to create pressure within the container 50. For this purpose, it includes at least one suction outlet opening 63 through which air is removed from the container and preferably delivered to a filter assembly 66. Figure 2 ).

[0065] The suction loading mechanism 60 also includes at least one suction inlet opening 62 in the container 50 through which milled material is drawn into the container due to depressurization in the container.

[0066] Container 50 includes an operational configuration in which it has a predetermined orientation relative to the ground. This configuration defines a portion considered as the bottom 56 of container 55. For example, in this configuration, the container has a longitudinal main extending direction X oriented parallel to the ground, for example, in... Figure 2 In the case of the large barrel shown.

[0067] The discharge mechanism 65 includes at least one discharge opening 70 from the container, and a selectively activating and deactivating mechanism 72 for opening and closing such discharge opening 70, such as an airtight door. The discharge opening 70 is located at or near the bottom 56 and is configured to be completely below the height H reached by the milling material trigger amount Q in the operating configuration. Conversely, the suction inlet opening 62 and suction outlet opening 63 are located higher relative to height H. Thus, the discharge opening 70 is physically and atmospherically shielded from the milling material amount Q relative to the suction openings 62 and 63, so that even if the discharge opening 70 is active, it does not affect the decompression of the container 50 required for suctioning the milled material, which can occur continuously and therefore simultaneously with the discharge.

[0068] Specifically, when the opening and closing mechanism 72 is opened to discharge milled material, the milled material substantially forms a closed shielding layer 75 within the container 50 of the discharge opening 70. This shielding layer 75 is operatively positioned between the discharge opening 70 and the suction openings 62 and 63, thereby preventing changes in suction pressure reduction within the compartment defined by the airtight container 50, thus configuring itself as a pressure shielding layer. The shielding layer 75 allows the discharge operation to be performed simultaneously with the suction operation at the input end. Therefore, as long as the amount of milled material remains greater than or equal to Q, both operations can be performed simultaneously within the same compartment.

[0069] Therefore, the control mechanism is configured to activate the discharge mechanism 65 if the amount of milled material in the container is ≥Q when the inlet suction mechanism is working, and preferably, to stop the discharge mechanism 65 if the amount of milled material becomes ≤Q.

[0070] A control mechanism 55 may also be provided, which is capable of delaying the start of discharge relative to the discharge permit condition of reaching a milled material quantity ≥ Q, so that it is advantageous to wait for the arrival of the transport vehicle for the milled material to be discharged without stopping the shaving machine.

[0071] Additionally, the control mechanism can be configured to activate the discharge mechanism 65 even when the suction loading mechanism 60 is not activated, so as to achieve complete discharge at the end of the work.

[0072] Activation of the emission control mechanism includes at least the opening of the opening and closing mechanism 72.

[0073] The discharge mechanism preferably also includes a conveying mechanism 80 for conveying milled material to the discharge opening 70, which is also preferably located below the height of the milled material corresponding to the quantity Q.

[0074] The conveying mechanism 80 includes, for example, a conveyor belt mechanism, a screw conveyor mechanism, etc., which is preferably arranged parallel to the bottom 56, for example, parallel to the longitudinal extension line X.

[0075] Alternatively, the discharge mechanism 65 may include a suction mechanism located at the output end of the discharge opening 70.

[0076] According to some alternative implementations, the control mechanism 55 can simply allow or deny the activation of the emission mechanism 65; for example, the emission mechanism 65 can be activated manually. In this case, the preferred device 2 includes a signaling mechanism for issuing a signal when the condition of milling material quantity ≥ Q is met.

[0077] In use, container 50 is initially empty, and discharge opening 70 is closed by door 72 in a preferably airtight manner, such as Figure 2 As shown.

[0078] In this initial step, the conveying mechanism 80 is stationary, while the suction loading mechanism 60 is operational, accumulating the milled material into the container 50.

[0079] Figure 3 The step shown is that when the amount of milled material contained in container 50 reaches the cutoff amount Q, it at least triggers permission to activate discharge mechanism 65, and more preferably triggers activation of their operation via control mechanism 55.

[0080] Figure 4 The steps of the discharge mechanism 65 and the suction loading mechanism 60 operating simultaneously are shown, in particular, the door 72 is open and the conveying mechanism 80 is in operation.

[0081] The discharge mechanism 65 preferably includes a protective mechanism 74 located within the container 50 for protecting the discharge opening 70. For example, these include a cover 74, such as a flange, that covers the area in front of the discharge opening 70 at a predetermined distance from the bottom 56, thereby defining an upper-defined access channel for milled material to the discharge opening 70. This cover advantageously supports a portion of the weight of the milled material on its top, thus preventing excessive force on the door 72 when closed.

[0082] Although the invention has been described so far with reference to a container containing only one sealed inner compartment, it is also applicable to containers having multiple sealed inner compartments, wherein at least one sealed inner compartment is connected to the suction loading mechanism 60, the discharge mechanism 65 and the quantification mechanism 58.

[0083] refer to Figure 6 and Figure 7 The illustration shows several variations of device 2, intended to suggest that there are no limitations on how the device can be implemented in vehicle form (whether motorized or not). For example, these variations show that container 50 is mounted on a railway freight car or equipped with rails, rather than as... Figure 1 It was installed on a truck like that.

[0084] Advantageously, milled material can be continuously pumped in without stopping the burring machine 1, including during discharge.

[0085] Advantageously, there is no need to stop the chiseling or suction in order to connect and disconnect the truck that transports the milled material to the discharge mechanism 65.

[0086] General Explanation of Terms

[0087] In understanding the purpose of this invention, the term "comprising" and its derivatives as used herein are intended as open-ended terms that indicate the presence of declared features, elements, components, groups, integers, and / or steps, but do not exclude the presence of other undeclared features, elements, components, groups, integers, and / or steps. The same applies to words with similar meanings, such as "comprising," "having," and their derivatives. Furthermore, when the terms "part," "segment," "part," "component," or "element" are used in the singular, they may have a dual meaning of a single part or multiple parts. As used herein to describe the above-described embodiments(s), the following directional terms "forward," "backward," "above," "below," "vertical," "horizontal," "below," and "lateral," as well as any other similar directional terms, refer to the embodiments described in the operating position. Finally, the degree terms such as "substantially," "approximately," and "generally" as used herein are intended as reasonable deviations from modified terminology so that the final result does not change significantly.

[0088] Although only selected embodiments have been chosen to illustrate the invention, those skilled in the art will understand from this specification that various modifications and variations can be made without departing from the scope of the invention as defined by the appended claims. For example, the size, shape, position, or orientation of individual components can be modified as needed and / or desired. Intermediate structures may be provided between directly connected or contacting components. The function of one element can be implemented by two elements, and vice versa. The structure and function of one embodiment can be used in another embodiment. All advantages of a particular embodiment do not necessarily have to be present simultaneously. Any feature that is original compared to the prior art, either alone or in combination with other features, should also be considered as a separate description by the applicant of another invention, including the structural and / or functional concepts embodied in such features. Therefore, the above description of embodiments according to the invention is for illustrative purposes only and is not intended to limit the invention, which is defined by the appended claims and their equivalents.

Claims

1. A movable suction device for milling materials, comprising: - At least one compartment (50); - A suction loading mechanism (60) located at the input end of the compartment is configured to depressurize the compartment (50) relative to the external environment and is configured to load the milling material into the compartment by suction generated by such depressurization; - A discharge mechanism (65) located at the output end of the compartment (50) is configured to discharge the milled material from the compartment (50). The suction device is characterized in that it comprises: - A detection mechanism (58) configured to detect the presence of a milled material shielding layer (75) between the suction loading mechanism (60) and the discharge mechanism (65); - A control mechanism (55), operably connected to the detection mechanism (58), to enable the discharge mechanism (65) when the detection mechanism detects the presence of the milled material shielding layer (75) during operation of the suction loading mechanism (60).

2. The apparatus according to claim 1, characterized in that, The discharge mechanism (65) includes at least one discharge opening (70), and the suction loading mechanism (60) includes at least one suction inlet opening (62) configured to introduce air and milling material into the compartment, and at least one suction outlet opening (63) configured to remove air from the compartment to generate the pressure reduction. The device is characterized in that it comprises: - A quantification mechanism (58) is configured to detect whether the milled material in the compartment has reached a predetermined amount Q, wherein the compartment is configured such that the predetermined amount Q is substantially contained therein to form a closed shield (75) for the discharge opening (70), the closed shield (75) being located between the discharge opening (70) on one side and the suction inlet opening (62) and suction outlet opening (63) on the other side. - A control mechanism (55), operably connected to the quantification mechanism (58), is configured to allow the discharge mechanism (65) to be activated during operation of the suction loading mechanism (60) when the amount of milled material in the compartment is ≥Q.

3. The apparatus according to claim 2, characterized in that, The shielding layer (75) is configured to provide a suction decompression shielding layer sufficient to allow the suction loading mechanism and the discharge mechanism to operate simultaneously.

4. The apparatus according to any one of claims 2 or 3, characterized in that, The control mechanism (55) is configured to control the activation of the discharge mechanism (65) during operation of the suction mechanism when the amount of milled material in the compartment is ≥Q, and to stop the discharge mechanism when the amount is ≤Q.

5. The apparatus according to claim 4, characterized in that, The control mechanism (55) is configured to allow delayed discharge relative to the condition that the milling material quantity = Q is reached.

6. The apparatus according to any one of claims 2 to 5, characterized in that, The emission mechanism (65) includes at least one opening and closing mechanism (72) for the at least one emission opening (70), the opening and closing mechanism (72) including at least one airtight door that can be controlled by the control mechanism (55).

7. The apparatus according to any one of claims 2 to 6, characterized in that, The discharge mechanism (65) includes a protection mechanism (74) for protecting the discharge opening (70), the protection mechanism (74) being located within the compartment (50) to cover the area in front of the discharge opening (70), thereby defining an upper-defined entry channel for the milled material to the discharge opening (70).

8. The apparatus according to any one of claims 2 to 7, characterized in that, The discharge mechanism (65) includes a conveying mechanism (80) for conveying the milled material to the discharge opening (70), wherein the discharge opening and the conveying mechanism (80) are located below the height H of the milled material corresponding to the quantity Q.

9. A device for roughening and suctioning related milled materials, characterized in that, The device includes at least one suction device according to any of the preceding claims and at least one shaving machine (1), the shaving machine including at least one shaving tool (20) and a suction shroud (100) coupled to the tool, wherein the device and the machine are configured to move at least horizontally relative to the ground and are operably connected to each other via at least one suction conduit 4, the suction conduit being between the suction shroud and the inlet suction mechanism (65).

10. The device according to claim 9, characterized in that, The shaving machine includes: - A bracket (5) and a base frame (10), the bracket and the base frame being configured to allow movement relative to the ground; - At least one operating arm (15) capable of rotating about a horizontal axis Y' relative to the bracket. - At least one chiseling tool (20) is placed at the distal end of the arm (15); - The burring tool (20) includes a frame (30) and a milling cutter (40), the milling cutter (40) being supported by the frame and positioned to rotate about the milling cutter axis Y'', wherein the milling cutter axis has at least a horizontal orientation; - The burring tool (20) includes a suction shield (100) configured to partially surround the milling cutter. - The cover (100) includes an opening (110) that defines a milling and suction area (112) in front of it, through which the milling cutter is exposed to the surface to be roughened.

11. A method for chiseling and suctioning the milled material generated by said chiseling, characterized by the following steps: - During the burring operation, milled material is continuously generated through burring; - Provide at least one compartment for receiving the milled material; - The milling material is loaded into the compartment by suction starting of the suction loading mechanism (60), which depressurizes the compartment relative to the external environment, wherein the depressurization occurs during the chiseling operation; - A discharge mechanism (65) is provided for discharging the milled material from the compartment; - Detect the presence of a milled material shielding layer (75) between the suction mechanism (60) and the discharge mechanism (65) in the compartment; - When the presence of the shielding layer (75) is detected, the milling material is discharged from the compartment by operating the discharge mechanism (65), and the milling material is continuously drawn in by the suction loading mechanism (60) during the discharge, thereby generating the milling material for simultaneous discharge and loading during the chiseling operation.

12. The method according to claim 10, characterized in that, When the presence of the shielding layer is not detected, the discharge mechanism (75) is stopped, and the suction loading mechanism (60) continues to perform suction.

13. The method according to claim 11 or 12, characterized in that, The emission is delayed relative to the moment when the presence of the shielding layer (75) is detected.

14. The method according to any one of claims 11 to 13, characterized in that, The shielding layer (75) is detected by detecting the amount of milled material Q in the compartment.

Images