Self-propelled soil compaction machine, in particular roller or tandem roller, and method for reducing the noise pollution within a driver's cab of a self-propelled soil compaction machine resulting from the operation of a vibration excitation device

Abstract

The invention relates to a self-propelled soil compaction machine, in particular a roller or a tandem roller, and a method for reducing the noise pollution within a driver's cab of the soil compaction machine resulting from the operation of a vibration excitation device of a self-propelled soil compaction machine, in particular a roller or a tandem roller.

Description

[0001] The invention relates to a self-propelled soil compaction machine, in particular a single-drum roller or a tandem roller. Furthermore, the invention relates to a method for reducing the noise pollution within a driver's cab of a self-propelled soil compaction machine, in particular a single-drum roller or a tandem roller, resulting from the operation of a vibration excitation device.

[0002] Soil compaction machines of this type are described in the prior art, for example, in EP3491192B1 and EP3861170A1. Such soil compaction machines are typically used in earthworks and road construction to compact the subsoil. These machines are self-propelled and feature a drive motor, such as an internal combustion engine and / or an electric motor, which provides the drive power required for the soil compaction machine's movement and operation. These machines typically comprise a machine frame as the essential supporting structure.

[0003] Typically, at least one soil compaction drum with at least one vibration excitation device is mounted directly or indirectly on the machine frame so that it can rotate about a rotation axis. The soil compaction drum is, in particular, a substantially hollow-cylindrical support structure whose outer surface is either smooth and cylindrical, as in the case of so-called smooth-surface drums, or whose outer surface is three-dimensionally deformed relative to a cylinder, as in the case of so-called polygon drums, or whose outer surface is equipped with additional devices, as in the case of so-called sheepsfoot drums or crusher drums.Vibration excitation devices are devices whose operation imposes vibration loads on the drums themselves, enabling a dynamic compaction process during soil compaction, as opposed to a purely static compaction effect dependent on the machine's weight. Such vibration excitation devices can, in particular, be so-called unbalance exciters, in which an unbalanced mass, mounted eccentrically with respect to a rotational axis, is rotated about this rotational axis. The arrangement and specific design of these vibration excitation devices can vary. What these vibration excitation devices have in common, however, is that they impose vibrations on the compaction drum during rotational operation. More than one vibration excitation device can also be arranged within a drum.The vibration excitation device can thus be designed as a circular exciter, directional oscillator and / or oscillation exciter.

[0004] In terms of its specific design, the soil compaction machine can, for example, be designed as a roller compactor. Typical for these soil compaction machines is the design of the machine frame as an articulated machine frame with a front frame and a rear frame connected to each other via an articulated joint. A pair of rubber wheels is often mounted on the rear frame together with the drive motor. The front frame, on the other hand, can be designed, in particular, in the form of a bearing fork that supports a front compaction drum. Alternatively, the soil compaction machine can also be designed as a tandem roller and comprise a front and a rear soil compaction drum. Tandem rollers are known in various designs.For example, the tandem roller can also be equipped with an articulated machine frame, so that the drums arranged on the front and rear sections are connected to each other via an articulated joint. Alternatively, so-called pivot-steered soil compaction machines are known, in which the front and rear drums are connected to the machine frame via a pivot with an at least essentially vertical steering axis. The special feature of these machines in practical use lies in their crab steering capability.

[0005] These soil compaction machines are typically operated from a driver's cab supported by the machine frame and enclosing an interior space, within which an operator's workstation for the soil compaction machine operator is located. Such driver's cabs are known in the art and typically refer to a unit enclosing the operator's workstation, for example, to provide weather protection and / or a workplace that is air-conditioned and / or insulated from the outside environment. Such driver's cabs frequently include at least one openable and closable access opening as well as glazed wall sections to enable a good overview of the outside environment from the interior of the soil compaction machine while the machine is driving and operating.Additionally, one or more openable windows may be provided, for example, so that an operator inside the cab can lean out of the cab in certain situations, or similar. Overall, the cab has at least one door and / or window unit that can be adjusted between an open and a closed position. Essential elements of the cab may include side walls, a rear wall, a front wall, a floor wall, and a roof wall, which together enclose the interior of the cab.

[0006] However, the driver's cabs often used in soil compaction machines often exhibit a resonant frequency when the door / window unit is open, which at least in phases coincides with the vibration frequency of the soil compaction machine's vibration excitation system. This can lead to a significant increase in noise inside the driver's cab, specifically a low-frequency humming, commonly referred to as a "rumbling."

[0007] In the case of increased noise levels in the cabin interior, numerous countermeasures have already been described in the state of the art. However, the implementations known to date all have significant disadvantages for specific applications. Conventional soundproofing measures, such as the use of sound-absorbing dampening materials, have proven ineffective. The principle of "counter-noise" is also known from the state of the art. This attempts to counteract a disturbing sound source by generating counter-noise and ultimately reduce the resulting amplitude in a limited space, such as the driver's cabin in this case.

[0008] However, effective reduction of the "rumble" in a specific application requires a relatively powerful low-frequency counter-noise source for effective counter-noise measures. However, due to the special requirements of a soil compaction machine driver's cab in terms of cost and spatial dimensions, this source should also be comparatively small in size and inexpensive to manufacture. Commonly used loudspeakers typically used for counter-noise applications are too small to generate sufficiently high sound levels in the relevant frequency range, for example, approximately 30 Hz. Subwoofers designed for such frequency ranges are often comparatively bulky and require a lot of power to achieve the required volume. Furthermore, such subwoofers are too expensive.

[0009] Based on this, it is therefore the object of the invention to provide a way of reducing the “rumbling” or noise pollution for the operator of a soil compaction machine of this type effectively and at the same time using the most cost-effective means possible.

[0010] The problem is solved with a self-propelled soil compaction machine and a method according to the independent claims. Preferred developments are specified in the dependent claims.

[0011] Starting from a generic soil compaction machine and referring to such a generic soil compaction machine as described above, specifically a self-propelled soil compaction machine, in particular a single-drum roller or a tandem roller, comprising a machine frame, at least one soil compaction drum with at least one vibration excitation device, a driver's cab carried by the machine frame and enclosing an interior space, an operating workstation arranged within the interior space for an operator of the soil compaction machine, wherein the driver's cab has at least one door and / or window unit adjustable between an open position and a closed position, the object is achieved by providing an air flow generation device which is designed and positioned such that, in an activated state, it effects an air flow within an air flow guide.One aspect of the invention thus relates to a device with the aid of which an air flow can be generated which is used, in the manner described in more detail below, to reduce the "rumbling" occurring within the driver's cab or perceptible by the operator inside the driver's cab when the door and / or window unit is opened and the vibration excitation device is in an activated state or the at least one drum is subjected to vibrations. For this purpose, the air flow generation device ideally comprises a driven air conveying device which is designed such that it moves a volume of air in a defined direction per unit of time. For this purpose, it can be provided, for example, that the air conveying device draws in air from the outside environment of the driver's cab and conveys it into the interior of the driver's cab, in particular in the manner described in more detail below.Furthermore, an air flow guide or an air flow guiding device is provided, such as a duct and / or shaft and / or hose and / or pipe, thus a device that enables the targeted further and / or diversion and thus guidance of the conveyed air volume or the air flow. Finally, it is provided that the air flow generated by the air flow guiding device is at least partially fed to a likewise provided interruption device, which is designed such that the air flow fed to it towards a downstream air flow outlet into the interior of the driver's cab is at least partially periodically interrupted or reduced by it. The interruption device thus makes it possible to set the air flow into vibration in a controlled manner and thus ultimately to generate the counter-sound required for the desired counter-sound effect in a controlled manner.The air flow generated by the air flow device, for example a fan, which is particularly relatively uniform in terms of its volume flow, thus exits from an outlet opening downstream of the interruption device in an oscillating manner into the interior of the driver's cab and can thus be used as a counter-noise source.

[0012] With regard to the specific design of the interruption device, there is fundamentally a wide range of variations. However, it is preferred if the interruption device is adjustable alternately or alternately between a maximum release position and a minimum release position or a blocking position. In this case, the interruption device is thus designed such that it pulsates the air flow from the air flow generation device, which flows essentially uniformly, in particular with regard to the volume flow, by alternately increasing and decreasing the air flow cross-section through which the air flow must pass on its way to the outlet opening. The "increase" can occur up to a maximum release position or a position in which the air flow cross-section through which the air flow must pass at the level of the interruption device is at its largest.Based on this, it can be provided that the interruption device reduces the air flow cross-section only up to a minimum release position, in which the air flow cross-section to be passed is reduced compared to the air flow cross-section at the maximum release position, in particular by at least 80%, very particularly by at least 90%, or even completely interrupts and / or redirects the air flow. In all these cases, a pulsating or "oscillating" air flow is maintained downstream of the interruption device.

[0013] The specific design of the interruption device is also highly variable, provided the desired effect, namely to cause the generated, essentially uniform air flow to oscillate, is sufficiently achieved. It is preferred if the interruption device comprises an air flow baffle, by adjusting which relative to a release opening formed by a housing of the interruption device, the maximum release position and the minimum release position or the blocking position can be set. The air flow baffle refers to a single- or multi-part component which is movable relative to a housing and a housing release opening in such a way that it periodically and repeatedly varies the size of the currently actually available resulting release opening over time, for example, comparable to a sliding door.The air flow baffle can thus be designed as an element that is alternately inserted into a flow channel transversely to the flow direction and removed again. In the simplest case, this can be a suitable sheet metal or a three-dimensional blocking body. Additionally or alternatively, it can be provided that the surface exposed to the air flow, which is introduced into the air flow by the air flow baffle or used for deflection and / or blocking, is designed as a flat and self-contained surface. Alternatively, however, this surface can also have one or more openings and / or swirl structures. Further additionally or alternatively, one or more three-dimensionally deformed surface structures, for example knobs, guide ribs or the like, can also be provided.

[0014] The interruption device preferably comprises a drive via which the alternating and periodic or alternately repeating adjustment between the maximum release position and the minimum release position or the blocking position is driven. This can be, for example, an electric motor and / or hydraulic and / or pneumatic drive. For this purpose, it can be provided that the interruption device is designed such that the adjustment movement of the air flow baffle relative to the housing is linear, arcuate, or rotational. In particular, it can thus be provided that the adjustable air flow baffle is designed as a rotor and the housing as a stator. The use of an air flow baffle designed as a rotor has the advantage of enabling a comparatively simple motor drive, which also enables the required rotational frequencies to be achieved in a reliable and precisely controllable and adjustable manner.In concrete terms, a stepper motor can be used for this purpose, for example.

[0015] The interruption device, in particular the air flow baffle, can in principle be arranged upstream of the air flow generation device or on its suction side, although it is preferred if the interruption device, in particular the air flow baffle, is arranged downstream of the air flow generation device or on its blowing side. It can be provided that the interruption device is designed such that the air flow flows out of the interruption device through an outlet opening, wherein the outlet opening has a contour in a projection plane perpendicular to the exit direction of the air from the outlet opening, which contour is preferably designed such that a reduction in the proportion of harmonics in the generated sound spectrum is achieved. The outlet opening can, for example, be designed such that it has a substantially rectangular or rounded contour in the projection plane.

[0016] The interruption device preferably comprises a drive motor, in particular an electric motor, which drives the adjustment movement of the air flow aperture relative to the housing of the interruption device.

[0017] The air flow aperture can be designed as a single-, double- or multi-blade aperture, in particular driven by a variable-speed electric motor for adjusting a speed and / or phase position.

[0018] The drive motor can drive a linear and / or rotating movement of the airflow diaphragm. The sliding and / or rotating direction can be alternating and / or reversible, or run exclusively in one direction. Specifically, the airflow diaphragm can also be a slider, a louvre, a plurality of louvres, or something similar.

[0019] In principle, the airflow generation device can be designed and arranged such that it is used exclusively for the aforementioned purpose of generating counter-noise. However, it is also possible for the airflow generation device to have a dual or multiple function and, for example, to be part of a cabin air conditioning device or an air conditioning module. It is possible, in particular, for only a portion of the airflow generated by the cabin air conditioning device to be fed to the interruption device.It can thus be provided that the air flow generation device has a deflection and / or branching device which is designed such that, depending on the situation, a portion of the air flow used for the cabin air conditioning is branched off and fed to the interruption device, for example only when part of the door and / or window unit is open and the "rumbling" described above occurs inside the driver's cab. In this case, the interruption device and a temperature unit of the cabin air conditioning system, with which the air can be heated and / or cooled, are thus preferably arranged parallel to one another. Additionally or alternatively, it can also be provided that these two elements are arranged in series and one behind the other in the direction of flow of the air flow. In this case, the air flow always passes through both units.This variant has proven particularly advantageous for retrofitting purposes.

[0020] Even though the resonance effect described above often occurs in a very narrow frequency range in known soil compaction machines, it can be advantageous if the soil compaction machine comprises a control unit designed to control and / or regulate the operation of the air flow generation device and / or the interruption device depending on an operating parameter and / or a status parameter of the soil compaction machine or a part thereof. This allows for a particularly effective response to changing sound situations and / or for the activation and / or deactivation of the air flow generation device and / or the interruption device to be fully automated, for example. Operating parameters refer to parameters relating to an operating status of the soil compaction machine.These can be one or more of the following parameters: activation / deactivation of the vibration excitation device and / or opening and / or closing state of one or more elements of the door and / or window unit, frequency and amplitude of the vibration exciter / drum(s), phase position of the excitation systems with multiple drums, etc. Status parameters can be currently given states of the soil compaction machine, such as the current noise situation inside the driver's cab and / or in the area outside the road construction machine, the operating state of an air conditioning and / or ventilation system, the actual noise level inside the driver's cab, etc. It goes without saying that an operating parameter can also determine a status parameter, and vice versa.

[0021] It is advantageous if the soil compaction machine has a sensor device that is in signal transmission connection with the control unit, which sensor device comprises, in particular, a microphone, in particular for detecting the current noise level in the interior of the driver's cab, and / or a driving speed sensor, and / or a door and / or window unit closure sensor, and / or a condition monitoring sensor for monitoring the operating state of the vibration excitation device, and / or a temperature sensor. The temperature sensor can, in particular, detect the actual temperature within the driver's cab and thus, for example, control an air conditioning device in addition to the air flow generation device and / or interruption device.In particular, for example, the conveying capacity of the air flow generation device can be increased if both counter-noise is to be generated and air conditioning of the interior of the driver's cab is to be achieved.

[0022] The air flow guide refers to the entirety of devices with the aid of which the generated air flow is guided, in particular from the intake point to the outlet opening in the interior of the driver's cab. For this purpose, the air flow guide can comprise pipes, ducts, shafts and / or the like. It can be advantageous if the air flow guide comprises one or more branches downstream of the air flow generation device and / or a flow convergence upstream of at least two air flow generation devices. These developments of the invention make it possible to draw in the air required to generate the air flow at multiple points or via multiple intake openings and / or to provide multiple outlet openings for the oscillating air into the interior of the driver's cab.It is possible that these outlet openings and / or intake openings are selected and / or varied depending on the situation, for example depending on which side of the driver's cab a door and / or window unit is currently open.

[0023] It is optimal if the air flow generation device is a fan, especially with a flow rate in the range of 10 m 3 / h up to 1000 m 3 , especially 25 m 3 / h up to 500 m 3 and especially 50 m 3 / h up to 200 m 3 / h. The fan preferably comprises a drive that is adjustable in terms of its speed and / or direction of rotation, in particular in order to be able to vary the speed of a rotor of the fan and adapt it to a current noise situation.

[0024] A further aspect of the invention relates to a method for reducing the noise pollution resulting from the operation of a vibration excitation device of a self-propelled soil compaction machine, in particular a single-drum roller or a tandem roller, within a driver's cab of the soil compaction machine, in particular a soil compaction machine according to the invention, as described above. In this respect, the above statements are also fully incorporated by reference for the method according to the invention.

[0025] According to the invention, it is now provided that counter-noise is generated, particularly within the driver's cab, using an airflow generation device, wherein an airflow is generated for this purpose when the airflow generation device is activated. This preferably occurs at least when, at the same time, the window and / or door unit is at least partially in an open position and / or the vibration excitation device is in an operating state in which it imparts vibrations to the at least one roller drum, in other words, the soil compaction drum vibrates.

[0026] The method according to the invention comprises feeding the generated air flow at least partially to an interruption device, causing the generated air flow to oscillate by the interruption device, and guiding the oscillated air flow into the interior of the driver's cab. For further details on these steps, reference is made to the preceding explanations. This provides a counter-noise source in the interior of the driver's cab, with the aid of which a counter-noise spectrum specifically targeted at the "rumble" that is comparatively specific to these machines is available and can be effectively reduced for the operator inside the driver's cab.

[0027] Ideally, the method according to the invention comprises controlling and / or regulating the operation of the air flow generation device and / or the operation of the interruption device using a control unit. This enables further optimized operation of the air flow generation device and / or the interruption device and thus further increased operating comfort for the operator of the soil compaction machine located in the driver's cab.

[0028] The control and / or regulation by the control unit ideally takes place as a function of at least one operating and / or state parameter, ideally as a function of a current sound load within the driver's cab and / or a phase position of the air flow emerging from the interruption device and / or a closed state of a door and / or window unit and / or an operating state of the vibration excitation device and / or a temperature, in particular an interior temperature of the driver's cab.

[0029] For this purpose, it can be provided that during operation of the soil compaction machine, at least one of these operating and / or state parameters is determined using one or more sensors, so that in this case the method comprises detecting at least one of these operating and / or state parameters using at least one sensor and transmitting the detected at least one operating and / or state parameter to the control unit.

[0030] Finally, for the method according to the invention, it is preferred if the control and / or regulation by the control unit comprises a control and / or regulation of at least one adjustment frequency of the interruption device, an alternating adjustment between a maximum release position and a minimum release position or a blocking position and / or a rotational speed of a rotor of the interruption device and / or a fan of the air flow generation device and / or a position of a flow divider and / or one or more flow valves.

[0031] The invention is explained in more detail below with reference to the exemplary embodiments shown in the figures. They show schematically: Fig. 1: a soil compaction machine of the tandem roller type; Fig. 2: a soil compaction machine of the single-drum roller type; Fig. 3: a schematic diagram of a soil compaction machine; Fig. 4: an alternative embodiment of an air duct; Fig. 5: a further alternative embodiment of an air duct; Fig. 6A: an interrupting device in a blocking position; Fig. 6B: the interruption device in a maximum release position Fig. 7: a graphic representation of a counter-sound effect; Fig. 8: a schematic diagram of a counter-noise device according to a further alternative embodiment; Fig. 9: a schematic diagram of a counter-noise device according to a further alternative embodiment; Fig. 10: a flow diagram of a method according to the invention; and Fig. 11A to 11C: further design alternatives of the interruption device.

[0032] Identical or functionally identical components are designated by the same reference numerals in the figures. Recurring components are not necessarily designated separately in each figure.

[0033] The Fig. 1 and Fig. 2 shows two soil compaction machines 1 in a side view. Fig. 1 relates to a soil compaction machine 1 of the tandem roller type and Fig. 2 shows a soil compaction machine 1 of the roller type. Both soil compaction machines have a drive motor 10 (not shown in detail in the figures), for example an internal combustion engine or electric motor, which provides the drive energy required for driving and working. The essential supporting structure of the machine in both cases is a machine frame 2, which is carried by driving devices 3. In the case of the machine shown in Fig. 1 shown tandem roller with a front and a rear soil compaction drum 4. In the case of the Fig. 2, the front driving device 3 is a soil compaction drum. The rear driving devices, however, are formed by a pair of wheels 6. In the interior of the soil compaction drums 4, which in this case are essentially hollow cylindrical, a vibration excitation device 5 of a known design is arranged, for example in the form of an unbalance exciter. Fig. 1 is a double-pedestal-steered tandem roller in which the two soil compaction drums are steerable via a steering pedestal 7 around a substantially vertically extending steering axis relative to the machine frame 2. In comparison, the roller train from the Fig. 2 is an articulated machine, in which the machine frame 2 has a front carriage 2a and a rear carriage 2b, which can be connected to each other via an articulated pendulum joint 8. It is also possible to construct the tandem roller from the Fig. 1 to be designed with an articulated steering system instead of the pivot steering system.

[0034] The soil compaction machines 1 are operated by an operator located within a driver's cab 9 carried by the machine frame 2. The driver's cab 9 can be arranged in a vibration-damped manner relative to the machine frame 2. The driver's cab 9 is a device which has an operator's seat 11 (and one or more control elements 11', as shown by way of example in the Fig. 3) and shields the existing operator workstation from the outside environment. For this purpose, the driver's cab 9 can comprise a front wall 12, a rear wall 13, two opposing side walls 14, a floor wall 15 and a roof 16 and thus form a self-contained cab structure that completely encloses an interior space. In particular, one or more transparent pane elements can be provided in the wall elements 12, 13 and 14 so that an operator located inside the driver's cab 9 can see the surroundings of the soil compaction machine 1 from the driver's cab 9. In particular, the wall elements 12, 13 and / or 14 can also comprise partially curved areas in which they can partially merge into one another. Overall, the driver's cab 9 thus provides a spatial compartment that demarcates the interior from the outside environment of the soil compaction machine 1.

[0035] Access from outside the soil compaction machine 1 into the interior can be achieved via one or more door units 17, which are adjustable, in particular pivotable or movable, between an open position releasing an access opening and a closed position closing this access opening. The door units 17 can be part of a side wall 14. Additionally or alternatively, the driver's cab 9 can have one or more window units 18, which are adjustable, in particular pivotable or movable, between an open position releasing a window opening and a closed position closing this window opening. A window unit 18 can be part of a door unit 17 and can be adjustable both relative to the machine frame 2 and relative to the respective door unit 17.

[0036] During driving and working of the soil compaction machine 1, operating situations may arise in which the operator located inside the driver's cab 9 wishes to open one of the door units 17 and / or one of the window units 18 and thus operate the soil compaction machine 1 with the door unit 17 and / or window unit 18 in the open position. This may, for example, allow for more precise navigation of the soil compaction machine 1 and / or ventilate the driver's cab 9. In these operating situations, the driver's cab 9 is therefore no longer completely closed, but has an opening towards the outside environment.If the vibration excitation device 5 is additionally activated in these operating situations, due to the fact that the driver's cab 9 often has a resonance frequency that corresponds to the vibration frequency of the vibration excitation device 5, an unpleasant increase in noise can occur in the interior of the driver's cab for the operator of the soil compaction machine located inside the driver's cab 9, specifically in the form of a comparatively low-frequency hum.

[0037] The Fig. The schematic diagram illustrated in Figure 3 now provides an effective and comparatively inexpensive way of generating a counter-noise specifically directed at this low-frequency hum in the interior of the driver's cab 89, thereby significantly increasing the operating comfort for the driver of the soil compaction machine 1, especially in this operating situation. The essential components for this are an air flow generation device 19 and an interruption device 20. During operation of the air flow generation device 19, a Fig. 3 is generated and is at least partially fed to the interruption device 20 in the manner described in more detail below.

[0038] The essential function of the air flow generating device 19 is to generate an air flow when activated. In the specific exemplary embodiment, the air flow generating device 19 is designed as a fan with a blade wheel of a conventional design. For drive, the air flow generating device 19 comprises a drive motor 21, in particular a variable-speed drive motor, for example an electric motor or a hydraulic motor. The air flow generated by the air flow generating device 19 is guided in an air flow guide 25 and thereby directed to the interruption device 20. For this purpose, the air flow guide 22 can be designed, for example, as a flow shaft and / or flow channel, and can also comprise hose and / or pipe elements, for example.

[0039] With respect to the air flow generated by the air flow guide, the interruption device 20 is arranged downstream of the latter. The essential function of the interruption device 20 is to at least partially periodically interrupt or reduce the air flow supplied to it during operation, for example, essentially continuously, ideally preferably almost uniformly in terms of volume flow, towards a downstream air flow outlet into the interior of the driver's cab 9. As a result, the air flow is set into vibration by the interruption device and can be used as a counter-noise source to reduce the unpleasant increase in noise in the interior of the driver's cab 9 when the vibration excitation device 5 is activated and a door and / or window unit 17 / 18 is in the open position.

[0040] For this purpose, the interruption device 20 is adjustable alternately between a maximum release position and a minimum release position or a blocking position, in particular rotating about a rotation axis in a direction of rotation, and can for this purpose comprise one or more air flow baffles 22 which, in rotational operation, alternately reduce / close a passage opening 23 through which the air flow is to pass and open it up to a maximum release position.

[0041] Regarding the flow pattern, the Fig. 3, air is initially sucked in (arrows a) from, for example, the outside environment of the soil compaction machine 1 via an intake opening 24. This can comprise a filter device, in particular a fabric filter. Downstream of the intake opening 24, the air flow generation device 19 is arranged in the present case, which feeds the sucked-in air within an air flow guide 25, designed, for example, as a shaft, to the interruption device 20 (arrows b). Starting from a maximum release position, this reduces or interrupts the incoming air flow to an outlet opening 25, via which the now "oscillating" air flow (arrows c; dashed line) exits into the interior of the driver's cab 9 from the air flow guide 26 or the air flow outlet.Overall, this arrangement can be used as a counter-noise source against resonance effects within the driver's cab 9 when the door and / or window unit 17 / 18 is open and the vibration excitation device 5 is activated.

[0042] The operation of the above-described arrangement for generating counter-noise can be controlled and / or regulated using a control unit 27. The control unit 27 can be connected to one or more sensors and / or actuators for signal transmission. For example, it can be provided that a microphone 28 and / or a closing state sensor 29 and / or a vibration excitation device sensor 30 are included in the soil compaction machine 1, with which operating and / or state parameters of the soil compaction machine 1, or at least parts thereof, can be determined and transmitted to the control unit 27. The microphone 28 can, for example, be used to determine and monitor the current sound level in the interior of the driver's cab 9. The closing state sensor 29 can be designed such that it monitors the closing state of one or more of the door and / or window units 17 / 18 and / or determines their opening width.This can be, for example, a contact switch or an angle sensor or similar. The vibration excitation device sensor 30 can, for example, be designed to determine whether the vibration excitation device 5 is currently activated and generating vibrations, or whether the soil compaction drum 4 is being subjected to vibrations or not. It may also be possible to use this sensor to determine a vibration frequency and / or a phase position. The sensors 28, 29, and 30 can be connected to the control unit 27 via suitable wired and / or wireless signal transmission connections 28', 29', and 30'.

[0043] It can be provided additionally or alternatively that the control unit 27 is designed such that it controls the operation of the air flow generation device 19 and / or the interruption device 20, in particular, for example, depending on one of the above-determined operating parameters and / or state parameters of the soil compaction machine 1 or a part thereof, and for this purpose, for example, controls one or more drives, in particular electric motors, via one or more of the control lines 20' and 21'.This makes it possible, for example, to optimally match the counter-noise generated to a currently existing noise load within the driver's cab 9 and, among other things, to put the above-described arrangement of air flow generation device 19 and interruption device 20 into operation only when, for example, a part of the door and / or window unit 17 / 18 is open and / or the vibration excitation device 5 is in activated operation (for an unbalance exciter, thus, for example, in rotating operation).

[0044] The Fig. 4 and Fig. 5 illustrate merely exemplary developments, inter alia, of the air flow guidance within the scope of the present invention.

[0045] In the embodiment according to Fig. 4, the air is drawn in via several intake openings, which in this case are carried out jointly via a single air flow generation device 19, specifically, for example, via a single fan. However, several fans can also be provided, in particular arranged in parallel. Accordingly, the air flow guide 25 is also branched to the extent that several air supply branches are converged upstream of the air flow generation device 19. Alternatively, it is also possible, for example, to provide a fan in each of the air supply branches.

[0046] In the embodiment according to the Fig. 5 also passes a branched air flow guide 25, whereby the air is drawn in via a common intake duct and branched off downstream of the air flow generation device 19 to two interruption devices 20 arranged parallel to one another. These can be operated jointly and / or alternately. Using this arrangement, it is possible, for example, to vary the exit point or exit location of the counter-noise within the driver's cab 9. A variation of the effective amplitude of the counter-noise is also possible, for example by selectively operating one and / or both of the interruption devices 20, static opening / closing of only one interruption device, in particular with simultaneous operation of the other interruption device 20, and / or phase control of the two interruption devices 20.

[0047] The Fig. 4 and Fig. 5 further illustrate that it is additionally or alternatively possible to arrange the drive 21 of the air flow generation device 19, particularly in the form of a fan drive, in front of or behind the respective air conveying element, such as a fan impeller, with respect to the air flow direction. The use of a radial fan is also possible.

[0048] It is understood that the number of air flow generating devices 19 and / or interrupting devices 20 and / or branches can be varied in many ways within the scope of the invention and, for example, can thereby be adapted in particular to individual designs of the respective driver's cab 9.

[0049] The Fig. 6A and Fig. 6B illustrate a particularly preferred embodiment of an air flow baffle 22 of an interruption device 20. In this case, the air flow baffle is designed as a rotor 31 rotating about a rotation axis R, which runs transversely, in particular perpendicularly, to the flow direction, with opening regions 22a and wall regions 22b arranged alternately in the direction of rotation. The cross-sectional width of the air flow guide 25 perpendicular to the air flow direction (arrow) is in this case greater than the maximum width of the opening regions 22a, so that the maximum size of the air flow for passage through the interruption device 20 is predetermined in this case by the design of the air flow baffle 22 itself. The width of the wall regions 22b is further dimensioned such that in this case, with the relative positioning shown in Fig. 6A, the air flow guide 25 is completely interrupted by the interruption device 20.The interruption device 22 further comprises a housing acting as a stator 32, which can, for example, perform a sealing and / or bearing function with respect to the internal rotor 31. If the rotor 21 thus rotates about its rotational axis R, it can be seen that an air flow flowing towards the interruption device 20, which is essentially uniform in terms of its volume flow (right side in the . Fig. 6A and Fig. 6B) is periodically interrupted by the rotating rotor and thus set into vibration.

[0050] The Fig. 11A, Fig. 11B and Fig. 11C illustrate further alternative embodiments of the interruption device 20 and the air flow aperture 22, respectively. Fig. 11A, the airflow baffle can also be designed as a blocking plate that is adjustable, particularly linearly, transversely to the airflow direction between the blocking position (dashed line) and the release position. The drive for this can be linear or, for example, via a crank mechanism. According to Fig. 11B, the air flow baffle 22 can also comprise one or more slats that are rotatably adjustable about a rotational axis extending transversely to the air flow direction, which, in their release position shown in dashed lines, rotate with their blocking surfaces in the direction of the air flow, and in their blocking position, are positioned with their blocking surfaces transversely to the air flow direction, whereby they can then form a substantially continuous blocking surface. The rotational movement can be circulating in one direction of rotation or alternately in two mutually opposite directions of rotation. According to the Fig. 11C, it is also possible for the air flow aperture 22 to be designed as a curved blocking surface, which is adjusted on a curved path for adjustment between the release position shown in dashed lines and the blocking position shown in solid lines. It is understood that the Fig. 11B and Fig. 11C obviously also include a drive motor 21 not explicitly shown in the figures.

[0051] The Fig. Figure 7 illustrates the desired counter-noise effect. It shows a graph plotting the sound amplitude A against time t. The sound waves 33a generated in the cabin interior due to the activated vibration excitation device 5 when the door and / or window unit 17 / 18 is at least partially open are shown by a solid line. With the aid of the device described above, comprising at least the air flow generation device 19 and the interruption device 20, opposing sound waves are now generated, in particular also by resorting to controlling and / or regulating measures using the control unit 27, so that, ideally, both sound waves cancel each other out at least within the interior of the driver's cabin 9 and are thus no longer perceived by the operator.

[0052] The Fig. 8 and Fig. 9 show further alternative or supplementary developments of the invention. A special feature of the Fig. 8 and Fig. The advantage of the arrangements shown in Figure 9 is that an air conditioning module 34, which is designed to heat and / or cool the air flowing through it, is integrated into the air flow guide. The air flow generated by the air flow generation device 19 can thus be used in a supplementary or alternative manner for a dual function, namely to generate counter-noise and for air conditioning purposes.

[0053] In the embodiment according to Fig. 8, the air flow generated by the air flow generating device 19 is first fed completely to the air conditioning module 34 and there either directed to a simple air outlet 35 within the driver's cab 9 and / or fed to the interruption device 20. To control the proportion of the conveyed air supplied to the air outlet 35 and the interruption device 20, one or more suitable valves 36, in particular flow valves, can be provided, for example, acting as flow dividers. Alternatively, in the arrangement according to Fig. 9, it is provided that the distribution of the air flow conveyed by the air flow generating device 19 or the conveyed air volume takes place upstream of the air conditioning module and the interruption device 20. In contrast to the previous embodiment, no conditioned air is supplied to the interruption device 20 in this case.

[0054] The Fig. 8 and Fig. 9 also illustrate further possible variations with regard to the sensor device 37, which is in signal communication with the control unit 27 and includes, among others, the sensors "microphone 28" and / or "vibration excitation device sensor 30." Furthermore, or alternatively, it may also be provided that an outside and / or inside temperature sensor 38 and / or a driving speed sensor 39 are present and in signal communication with the control unit 27 and are taken into account, for example, in the control and / or regulation of the anti-noise operation by the control unit 27.

[0055] Fig.Figure 10 illustrates a flowchart of a method 40 according to the invention for reducing the noise pollution within a driver's cab of a self-propelled soil compaction machine, in particular a single-drum roller or a tandem roller, resulting from the operation of a vibration excitation device of the soil compaction machine. The method is particularly suitable for use in one of the embodiments explained in relation to the preceding figures.

[0056] Accordingly, counter-noise is generated with the aid of an air flow generating device, wherein, for this purpose, an air flow is generated in an activated state of the air flow generating device (41), the generated air flow is at least partially fed to an interruption device (42), the generated air flow is set into vibration by the interruption device (43) and the vibrated air flow is guided into the interior of the driver's cab (44).

[0057] It can be provided that a control and / or regulation (45) of the operation of the air flow generating device and / or the operation of the interruption device is carried out with the aid of a control unit, wherein the control and / or regulation by the control unit is carried out as a function (46) of at least one of the operating and / or state parameters - a current noise level inside the driver’s cab, - a phase position of the air flow exiting the interruption device, - a driving speed of the soil compaction machine, - a closed state of a door and / or window unit, - an operating state of the vibration excitation device and / or - a temperature, especially the interior temperature of the driver's cab. For this purpose, measured values ​​can be obtained using one or more suitable sensors and transmitted to the control unit.

[0058] The control and / or regulation (45) by the control unit can specifically comprise a control and / or regulation of at least the adjustment frequency of the interruption device of an alternating adjustment between a maximum release position and a minimum release position or a blocking position and / or a rotational speed of a rotor of the interruption device and / or a fan of the air flow generation device and / or a position of a flow divider and / or one or more flow valves. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 3491192B1

[0002] EP 3861170A1

[0002]

Claims

[1] Self-propelled soil compaction machine (1), in particular a roller train or tandem roller, comprising - a machine frame (2), - at least one soil compaction drum (4) with at least one vibration excitation device (5), - a driver's cab (9) supported by the machine frame (2) and enclosing an interior space and - an operating workstation (11) arranged within the interior for an operator of the soil compaction machine (1), wherein the driver's cab (9) has at least one door and / or window unit (17, 18) adjustable between an open position and a closed position, characterized bythat an air flow generating device (19) is provided which is designed and positioned such that, in an activated state, it effects an air flow within an air flow guide (25), wherein the air flow guide (5) supplies the air flow at least partially to an interruption device (20) which is designed such that the air flow supplied to it is at least partially periodically interrupted or reduced by it towards a downstream air flow outlet (26) into the interior of the driver's cab (9). [2] Self-propelled soil compaction machine (1) according to claim 1, characterized by that the interruption device (20) is alternately adjustable between a maximum release position and a minimum release position or a blocking position. [3] Self-propelled soil compaction machine (1) according to claim 2, characterized bythat the interruption device (20) comprises an air flow aperture (22), by means of which the maximum release position and the minimum release position or the blocking position can be set relative to a release opening formed by a housing of the interruption device (20). [4] Self-propelled soil compaction machine (1) according to claim 3, characterized by that the interruption device (20) is designed such that the adjusting movement of the air flow baffle (22) relative to the housing is linear, arcuate or rotary. [5] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized by that the air flow flows out of the interruption device (20) through an outlet opening, wherein the outlet opening has a rectangular contour in a projection plane perpendicular to the exit direction of the air from the outlet opening. [6] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized by that a drive motor, in particular an electric motor, is included in the interruption device (20), which drives the adjusting movement of the air flow baffle (22) relative to the housing of the interruption device (20). [7] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized by that the air flow generating device (19) is part of a cabin air conditioning device (34), wherein in particular only a part of the air flow generated by the cabin air conditioning device (34) is fed to the interruption device (20). [8] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized byin that the soil compaction machine (1) comprises a control unit (27) which is designed such that it controls the operation of the air flow generating device (19) and / or the interruption device (20) as a function of an operating parameter and / or a state parameter of the soil compaction machine (1) or a part thereof. [9] Self-propelled soil compaction machine (1) according to claim 8, characterized by that the soil compaction machine (1) comprises a sensor device (37) which is in signal transmission connection with the control unit (27), in particular - a microphone (28) and / or - a vehicle speed sensor (39) and / or - a closing state sensor (29) of a door and / or window unit (17, 18) and / or - a condition monitoring sensor (30) for monitoring the operating state of the vibration excitation device (5) and / or - comprises a temperature sensor (38). [10] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized by that the air flow guide (25) - a branch downstream of the air flow generating device (19) and / or - a flow merging upstream of at least two air flow generating devices (19). [11] Self-propelled soil compaction machine (1) according to one of the preceding claims, characterized by that the air flow generating device (19) is a fan, in particular with a conveying capacity in the range of 50 m 3 / h up to 200 m 3 / h. [12] Method for reducing the noise pollution resulting from the operation of a vibration excitation device (5) of a self-propelled soil compaction machine (1), in particular a roller train or a tandem roller, within a driver's cab (9) of the soil compaction machine (1), in particular a soil compaction machine (1) according to one of claims 1 to 11, characterized by , generating a counter sound by means of an air flow generating device (19), wherein - in an activated state of the air flow generating device (19) an air flow is generated, - the generated air flow is at least partially fed to an interruption device (20), - the generated air flow is set into vibration by the interruption device (20) and - the vibrating air flow is directed into the interior of the driver's cab. [13] Method according to claim 12, characterized by that the operation of the air flow generating device (19) and / or the operation of the interrupting device (20) is controlled and / or regulated by means of a control unit (27). [14] Method according to claim 13, characterized by that the control and / or regulation by the control unit (27) is carried out as a function of at least one of the following operating and / or status parameters: - current noise levels inside the driver's cab; - a phase position of the air flow exiting the interruption device (20); - a driving speed of the soil compaction machine (1); - a closed state of a door and / or window unit; - an operating state of the vibration excitation device; - a temperature, especially the interior temperature of the driver's cab. [15] Method according to one of claims 13 or 14, characterized bythat the control and / or regulation by the control unit (27) comprises a control and / or regulation of at least one of the following parameters: - Adjustment frequency of the interruption device (20) of an alternating adjustment between a maximum release position and a minimum release position or a blocking position; - rotational speed of a rotor of the interruption device (20) and / or a fan of the air flow generating device (19); - Position of a flow splitter and / or one or more flow valves.

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