Road milling machine with a dust extraction system

Abstract

road milling machine (1), with - a machine frame (6), - at least three driving devices (2, 3), wherein at least two driving devices (3) are driven and at least one driving device (2) is steerable, - at least one milling roller (11) for processing the floor covering (4), - at least one extraction device (12) for extracting air contaminated with dust and vapors, wherein the extraction device (12) has at least one exhaust pipe (13) with at least one first pipe section (24) having at least one first cross-section (26) and at least one second pipe section (20) having at least one second cross-section (22), wherein the second cross-section (22) is smaller than the first cross-section (26), wherein an intake duct (18) has an inlet opening (30) and an outlet opening (28), wherein the outlet opening (28) opens into the exhaust pipe (13) in the area of ​​the second pipe section (20), wherein the air contaminated with dust and vapors can be drawn in at the inlet opening (30), characterized in that the extraction device (12) has a fan (16) which is arranged such that the air contaminated with dust and vapors is not drawn in by the fan (16). flows through it.

Description

[0001] The invention relates to a road milling machine according to the preamble of claim 1.

[0002] Common road milling machines typically consist of a machine frame and at least three drive units, of which at least two are driven and at least one is steerable. Furthermore, a road milling machine has at least one milling drum for processing the road surface. An extraction system for removing air contaminated with dust and fumes may also be included.

[0003] Milling the ground surface creates dust and fumes that worsen the working conditions for the machine operator on the driver's platform and other operating personnel around the milling machine, and may obstruct the view of passing traffic.

[0004] WO 03 / 100172 A1 discloses an extraction device for a milling machine, which is connected to a first channel section associated with the transport equipment and extracts contaminated air during milling, essentially in the direction of material transport, within the first channel section. US 6,733,086 B1 discloses a vacuum system attached to a milling machine for extracting material removed from the surface of a roadway by the machine's milling drum. The milling machine comprises a frame, a drive system for moving the machine, a milling drum mounted on the frame for rotation about its axis, and a conveyor belt for removing the material removed by the milling drum. The vacuum system comprises a vacuum pump with an air inlet and an air outlet, and a nozzle mounted behind the milling drum with an opening for receiving the material removed from the surface by the drum.

[0005] The current state of the art often has the disadvantage that a fan of the extraction system is located in the dirty area, meaning that the air contaminated with dust and vapors flows through the fan.

[0006] The invention is based on the objective of creating a road milling machine in which the dust and vapors produced during the milling process can be effectively extracted without contaminating the fan of the extraction device.

[0007] The features of claim 1 serve to solve this problem.

[0008] The invention advantageously provides that at least a first exhaust pipe has at least a first pipe section with a first cross-section and at least a second pipe section with a second cross-section, wherein the second cross-section is smaller than the first cross-section, wherein an intake duct has an inlet opening and an outlet opening, wherein the outlet opening opens into the exhaust pipe in the area of ​​the second pipe section, and wherein the air contaminated with dust and vapors can be drawn in at the inlet opening.

[0009] The present invention has the advantage that the Venturi effect is used to extract air contaminated with dust and vapors particularly effectively.

[0010] The first pipe section is located upstream of the second pipe section in the direction of airflow. "In the direction of airflow" refers to the direction in which the air flows through the extraction system, particularly through the exhaust pipe.

[0011] The extraction device may also include a fan connected to the first pipe section, so that air can be blown from the fan into the extraction pipe.

[0012] The second pipe section lies downstream of the first pipe section in the direction of airflow. "In the direction of airflow" also means in the direction in which the air is blown by the fan.

[0013] The present invention has the advantage that the fan is arranged in such a way that it is located on the clean side, i.e., the air contaminated with vapors and dust does not flow through the fan.

[0014] A fan is understood to be a driven turbomachine that preferably uses an impeller mounted in a housing to move air, preferably achieving a pressure ratio between 1 and 1.3 between the intake and discharge sides. This is distinct from turbomachines with a pressure ratio greater than 1.3, which are compressors. A fan can also be called a blower or ventilator. Fans can be of the radial or axial type.

[0015] The exhaust pipe can be made of one or more parts. In the case of a multi-part exhaust pipe, the individual parts can be permanently or detachably connected.

[0016] The exhaust pipe can extend along a first longitudinal axis, at least in the area of ​​the first pipe section, wherein the first longitudinal axis is arranged such that it runs substantially perpendicular to the floor covering, preferably at an angle between 70° and 90° to the floor covering. The exhaust pipe can extend along a second longitudinal axis, at least in the area of ​​the second pipe section, wherein the second longitudinal axis preferably runs parallel to the first longitudinal axis. The second longitudinal axis can also be arranged such that it runs substantially perpendicular to the floor covering, preferably at an angle between 70° and 90° to the floor covering. If the first and second pipe sections are arranged concentrically to each other, the first and second longitudinal axes form a common longitudinal axis.

[0017] The arrangement of the first and / or second longitudinal axis essentially perpendicular to the floor covering has the advantage that coarse dirt particles in the contaminated air, which are too heavy to be carried along by the air, fall to the ground due to gravity and in this case fall downwards along the first and / or second longitudinal axis of the exhaust pipe towards the floor covering.

[0018] The fan can be arranged in such a way that the air from the fan enters the exhaust pipe essentially perpendicular to the first and / or second longitudinal axis of the exhaust pipe.

[0019] The intake duct can open into the exhaust pipe essentially perpendicular to the first and / or second longitudinal axis of the exhaust pipe.

[0020] The intake duct can extend into the exhaust pipe. This has the advantage that the flow velocity at the exhaust duct's outlet is particularly high, and the air contaminated with dust and fumes is carried along very effectively.

[0021] The exhaust pipe can have a first opening and a second opening, with the second opening being located above the first opening and the contaminated air being able to escape from the second opening.

[0022] The first opening of the exhaust pipe can be located on a side facing the floor covering.

[0023] This has the advantage that coarse dirt particles, which are not carried away by the air, can fall towards the floor covering.

[0024] A collection container can be installed at the first opening of the exhaust pipe. This container can catch the particularly coarse debris that falls towards the floor.

[0025] The fan can be positioned below the intake duct and laterally next to the exhaust pipe relative to the first and / or second longitudinal axis of the exhaust pipe.

[0026] The outlet opening of the intake duct can be located above the area where the air blown by the fan is introduced into the exhaust pipe.

[0027] The present invention has the advantage that the fan is arranged in such a way that the coarse dirt particles do not fall onto the fan, but fall past it.

[0028] A driver's cab can be provided, with the second opening of the exhaust pipe located above the driver's cab.

[0029] The exhaust pipe can have a third pipe section arranged behind the second pipe section in the direction of flow, wherein the third pipe section has a third cross-section that is larger than the second cross-section of the second pipe section.

[0030] A housing, in particular a milling drum housing or milling drum box, can be arranged around the milling drum, wherein an opening can be arranged on one side, in particular on the rear side in the direction of travel, into which the intake channel opens and preferably the opening can form the inlet opening of the intake channel.

[0031] In this way, the contaminated air is extracted directly at the milling drum housing.

[0032] The road milling machine can be a small milling machine, wherein the small milling machine has at least two rear chassis and the milling drum is arranged between the rear chassis.

[0033] The extraction device can be demountable, and facilities can be provided to which a conveyor belt can be attached, so that a conveyor belt can be connected instead of the extraction device.

[0034] The extraction system is therefore particularly intended when no conveyor belt is provided on the road milling machine.

[0035] The exhaust pipe can have a fourth pipe section arranged above the first and second pipe sections, wherein the fourth pipe section is designed as a flexible hose that is expandable in length.

[0036] This has the advantage that the exhaust pipe can be attached to a height-adjustable roof of the road milling machine, where the roof can be the roof of the driver's cab.

[0037] In the following, an embodiment of the present invention will be explained in more detail with reference to the drawings.

[0038] They show: Fig. 1 A road milling machine according to the present invention, Fig. 2 an extraction device, Fig. 3 the extraction system Fig. 2 in side view, and Fig. 4 the extraction system Fig. 3 on average.

[0039] Fig. Figure 1 showed a road milling machine 1 for processing the pavement 4. The road milling machine 1 has a machine frame 6 and at least three drive units 2, 3. At least two drive units 3 are powered and at least one drive unit 2 is steerable. However, the road milling machine can also have four drive units, all of which can also be powered. In the illustrated embodiment, the road milling machine is a small milling machine in which the milling drum 11, shown only with dashed lines, is arranged between the rear drive units 3. The drive units 2, 3 can be wheels or tracks. In the illustrated embodiment, the drive units are wheels. The road milling machine has a driver's platform 8 and a roof 62 above the driver's platform 8. The roof 62 can be height-adjustable relative to the driver's platform.

[0040] The rear drive units 3 can be height-adjustable relative to the machine frame 6. In the illustrated embodiment, lifting columns are provided for the rear drive units, with the aid of which the machine frame 6 can be height-adjusted. In this way, the milling drum 11 mounted on the machine frame 6 can also be height-adjusted. One of the two rear drive units 3 can be controlled by a column in the Fig. The outer end position shown in Figure 1 is pivoted inwards into a recess 7 of the machine frame 6, so that the outer edge of the pivoted drive unit 3 is approximately flush with the side of the road milling machine 1. In this way, on the side on which one of the rear drive units 3 is pivoted, the milling drum can be arranged so that it extends to the side of the machine frame 6 and preferably is flush with the side of the road milling machine 1, thus enabling milling close to the edge. This side, on which milling close to the edge is possible, is called the zero side.

[0041] In Fig. Figure 1 already shows the extraction device 12. In the illustrated embodiment, no transport device is provided. The milling drum 11 is arranged in a housing 10, in particular a milling drum box. An opening 15 is provided on the rear side 14 in the direction of travel. Behind the opening 15 is the inlet opening 30 ( Fig. 3) of the intake duct 18 ( Fig. 3) ordered.

[0042] The extraction unit 12 is more precisely described in the Fig. 2, Fig. 3 and Fig. Figure 4 shows the extraction device 12 having at least one exhaust pipe 13. The first exhaust pipe 13 has at least one first pipe section 24 and at least one second pipe section 20. The first pipe section 24 has at least one first cross-section 26, and the second pipe section 20 has at least one second cross-section 22. The second cross-section 22 is smaller than the first cross-section 26. The intake duct 18 has an inlet opening 30 and an outlet opening 28. The outlet opening 28 opens into the second pipe section 22 of the extraction pipe 13.

[0043] A fan 16 is arranged below the intake duct 18. This fan 16 is preferably arranged laterally next to the exhaust pipe 13. The terms "below" and "above" are used below to refer to the position relative to the floor covering. "Above" means further away from the floor covering, and "below" means closer to the floor covering. The exhaust pipe shown has a first longitudinal axis 46 in at least the first pipe section 24 and a second longitudinal axis 47 in the second pipe section 20. The first and second longitudinal axes 46, 47 are substantially perpendicular to the floor covering. The first and / or the second longitudinal axis 46, 47 preferably have an angle α between 70° and 90° with the floor covering 4.

[0044] The exhaust pipe 13 can have a fourth pipe section 60, which is arranged above the first and second pipe sections 24, 20, wherein the fourth pipe section 60 is designed as a flexible hose that is extendable in length. The flexible hose is designed in the shape of an accordion and can therefore extend in length.

[0045] This has the advantage that the exhaust pipe 13 can be attached to the height-adjustable roof 62 of the road milling machine 1, the roof 62 being a roof of the driver's cab 8.

[0046] As from Fig. As can be seen from Figure 4, the extraction duct 18 preferably projects into the exhaust pipe 13 by the amount X. In this way, the flow velocity in the exhaust pipe is particularly high in the area of ​​the outlet opening 28 of the extraction duct 18 and the contaminated air can be particularly well removed.

[0047] The exhaust pipe 13 can be made of one piece or multiple pieces. In this case, the exhaust pipe 13 is composed of several pieces. The exhaust pipe does not have to be straight. The exhaust pipe has a first and a second opening, with the second opening 34 being located above the first opening 36. The first opening 36 is located on the side facing the floor covering. The contaminated air can escape from the second opening 34.

[0048] A collection container 38 can be provided at the first opening 36 of the exhaust pipe 13, as shown. In the illustrated embodiment, the collection container 38 is open at the bottom. However, it can easily be closed with a lid. Alternatively, the collection container 38 can also be made of a flexible material and have its lower end folded over to close it.

[0049] The exhaust pipe 13 can also have a third pipe section 50, which has a third cross-section, wherein the third cross-section 52 is larger than the second cross-section 22 of the second pipe section 20. The cross-section of the exhaust pipe thus increases again in the direction of flow downstream of the inlet of the contaminated air. This has a particularly positive effect on the extraction of the contaminated air.

[0050] When dust is generated in the milling drum housing, it can enter the extraction duct 18 through the opening 15 and the inlet opening 30. The fan 16 blows air into the exhaust pipe 13. Because the air is blown into the first pipe section 24 and the second pipe section 20 has a smaller cross-section 22, the flow velocity in the second pipe section 20 is higher. This creates a negative pressure at the outlet opening 28 of the intake duct 18. The contaminated air is therefore drawn in through the intake duct 18.

[0051] The air blown into the exhaust pipe 13 by the fan 16 carries the contaminated air with it and directs it to the second opening 34, where the contaminated air can exit. If coarser dirt particles are present in the contaminated air that cannot be carried along by the air, they fall down the exhaust pipe 13 into the collection container 38. Since the fan 16 is located next to the exhaust pipe, i.e., next to the exhaust pipe and below the extraction duct 18 with respect to the longitudinal axis 46, even coarse dirt particles do not fall onto the fan 16. The contaminated air 18 also does not have to flow through the fan 16. The fan is therefore located on the clean side. In this way, the fan 16 has a longer service life and does not require cleaning as frequently.

[0052] The design of the extraction system allows the "Venturi effect" to be used particularly well, making extraction especially effective.

Claims

[1] Road milling machine (1), with - a machine frame (6), - at least three driving devices (2, 3), wherein at least two driving devices (3) are driven and at least one driving device (2) is steerable, - at least one milling roller (11) for processing the floor covering (4), - at least one extraction device (12) for extracting air contaminated with dusts and vapors, wherein the extraction device (12) has at least one exhaust pipe (13) with at least one first pipe section (24) having at least one first cross-section (26) and at least one second pipe section (20) having at least one second cross-section (22), wherein the second cross-section (22) is smaller than the first cross-section (26), wherein an intake duct (18) has an inlet opening (30) and an outlet opening (28), wherein the outlet opening (28) opens into the exhaust pipe (13) in the area of ​​the second pipe section (20), wherein the air contaminated with dusts and vapors can be drawn in at the inlet opening (30), characterized by , that the extraction device (12) has a fan (16) which is arranged in such a way that the air contaminated with dusts and vapors does not flow through the fan (16). [2] Road milling machine according to claim 1, characterized by , that the fan (16) is connected to the first pipe section (24) so ​​that air can be blown from the fan (16) into the exhaust pipe (13). [3] Road milling machine (1) according to claim 1 or 2, characterized by , that the exhaust pipe (13) extends at least in the first pipe section (24) along a first longitudinal axis (46), wherein the first longitudinal axis (46) is arranged such that it is substantially perpendicular to the floor covering (4), preferably having an angle (α) between 70° and 90° to the floor covering (4). [4] Road milling machine (1) according to claim 3, characterized by , that the fan (16) is arranged such that the air from the fan (16) enters the exhaust pipe (13) substantially perpendicular to the first longitudinal axis (46) of the exhaust pipe (13). [5] Road milling machine (1) according to any one of claims 1 to 4, characterized by , that the intake duct (18) protrudes into the exhaust pipe (13). [6] Road milling machine (1) according to any one of claims 1 to 5, characterized by , that the exhaust pipe (13) has a first opening (36) and a second opening (34), wherein the second opening (34) is arranged above the first opening (36) and the contaminated air can escape from the second opening (34). [7] Road milling machine according to claim 6, characterized by , that the first opening (36) of the exhaust pipe (13) is located on the side facing the floor covering (4). [8] Road milling machine according to claim 7, characterized by , that a collection container (38) is arranged at the first opening (36) of the exhaust pipe (13). [9] Road milling machine (1) according to any one of claims 3 to 8, characterized by , that the fan (16) is arranged below the intake duct (18) and relative to the first longitudinal axis (46) of the exhaust pipe (13) to the side of the exhaust pipe (13). [10] Road milling machine (1) according to any one of claims 6 to 9, characterized by, that a driver's platform (8) is provided, wherein the second opening (34) of the exhaust pipe (13) is located above the driver's platform. [11] Road milling machine (1) according to any one of claims 1 to 9, characterized by , that the exhaust pipe (13) has a third pipe section (52) which is arranged in the direction of flow behind the second pipe section (20), wherein the third pipe section (52) has a third cross-section (50) which is larger than the second cross-section (22) of the second pipe section (20). [12] Road milling machine (1) according to any one of claims 1 to 11, characterized by , that a housing (10), in particular a milling drum box, is arranged around the milling drum (11), wherein an opening (15) is arranged on one side (14), in particular on the rear side in the direction of travel, which is connected to the intake duct (18) and the opening (15) preferably forms the inlet opening (30) of the intake duct (18). [13] Road milling machine (1) according to any one of claims 1 to 12, characterized by , that the road milling machine (1) is a small milling machine, wherein the small milling machine has at least two rear chassis (3) and the milling drum (11) is arranged between the rear chassis (3). [14] Road milling machine (1) according to any one of claims 1 to 13, characterized by , that the extraction device (12) is demountable and that facilities are provided to which a conveyor belt can be attached, so that a conveyor belt can be connected instead of the extraction device (12). [15] Road milling machine (1) according to any one of claims 11 to 14, characterized by , that the exhaust pipe (13) has a fourth pipe section (60) which is arranged above the first and second pipe sections (24, 20), wherein the fourth pipe section (60) is designed as a flexible hose which is stretchable in its length.

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