Self-propelled surface processing machine

Abstract

A self-propelled ground processing machine, comprising: a traveling mechanism, a frame carried by the traveling mechanism (24), a power source accommodated on the frame for providing power for traveling operation and / or for ground processing operation, a working device for ground processing accommodated on the frame, and a cooling device for cooling the functional devices of the ground processing machine. The cooling device includes: - at least one heat exchanger assembly for transferring heat from a cooling medium to air, and - a blower assembly configured to generate a cooling air flow through the heat exchanger assembly and configured to generate a ventilation air flow flowing away from the power source in the region of the power source. The heat exchanger assembly and the ventilation volume of the ventilation air flow flowing away from the power source are provided on the suction side of the blower assembly, and the ventilation volume is arranged downstream of the heat exchanger assembly with respect to the cooling air flow, so that the ventilation air flow generated by the blower assembly meets the cooling air flow downstream of the heat exchanger assembly and upstream of the blower assembly.

Description

Technical Field

[0001] The present invention relates to a self-propelled surface processing machine, such as a road milling machine, in particular a cold milling machine for roads, an open-pit mining machine or a stabilizer. The surface processing machine comprises:

[0002] - a traveling mechanism by means of which the surface processing machine can be rollably erected on a foundation, and

[0003] - a frame carried by the traveling mechanism,

[0004] - a power source accommodated on the frame, the power source being used to provide power that can be used for the traveling operation or / and the surface processing operation of the surface processing machine,

[0005] - a working device for surface processing accommodated on the frame,

[0006] - a cooling device for cooling the functional devices of the surface processing machine, wherein the cooling device comprises:

[0007] - at least one heat exchanger assembly, which includes at least one heat exchanger, the at least one heat exchanger being used to transfer heat from a cooling medium to air, and

[0008] - a fan assembly, which is configured and arranged on the one hand to generate a cooling air flow through the heat exchanger assembly and which is configured and arranged on the other hand to generate a ventilation air flow flowing away from the power source in the region of the power source. Background Art

[0009] This surface processing machine configured as a road milling machine is known from DE 10 2014 008 749 A1. Specifically known from this document, an internal combustion engine as a power source and the aforementioned cooling device are provided between the driver's cab and the rear of the road cold milling machine. The known heat exchanger assembly includes two heat exchangers, and the two heat exchangers belong to different cooling circuits. In the first cooling circuit, the cooling medium circulates between the heat exchanger and the internal combustion engine and outputs again at the heat exchanger the heat previously contained in the cooling medium on the internal combustion engine. In the second cooling circuit, hydraulic oil operates as the cooling medium that outputs heat in the heat exchanger, and this hydraulic oil is used to drive the hydraulic motor of the travel drive. Here, the cooling air flows passing through the respective heat exchangers are strictly separated from each other by a partition wall because, based on the operating characteristics of the known road cold milling machine, there are to a certain extent complementary heat loads on the cooling medium of the internal combustion engine on the one hand and on the hydraulic oil on the other hand. During travel operation without surface processing, the internal combustion engine and its cooling medium are very slightly heat-loaded, while the hydraulic oil of the hydraulic motor forming the travel drive is very highly heat-loaded. During surface processing operation at a travel speed lower than the aforementioned travel operation but with a high driving force of the milling drum of the road milling machine, the hydraulic oil is only very slightly heat-loaded, while the internal combustion engine and its cooling medium are very highly heat-loaded. In reality, operation with a high driving force of the milling drum and at the same time a high travel speed does not actually occur. This also applies to the embodiment of the surface processing machine of the present application that preferably has a hydraulic motor type propulsion device and a milling drum as the working device.

[0010] Here, DE 10 2014 008 749 A1 teaches the use of a fan assembly to cool the air flowing through the heat exchanger and to extract air from the motor compartment. The internal combustion engine is housed in the motor compartment.

[0011] DE 10 2014 008 749 A1 specifically teaches in one embodiment that the heat exchanger and the internal combustion engine are arranged on the suction side of the fan assembly, and the air extracted from the area of the internal combustion engine is mixed with the fresh air that is also sucked in and passes through the heat exchanger in a suction movement. DE 10 2014 008 749 A1 also teaches in other embodiments that the heat exchanger and the internal combustion engine are arranged on the pressure side of the fan assembly, and the air sucked in by the fan assembly moves through by being squeezed at the heat exchanger and the internal combustion engine.

[0012] The disadvantage of the first-mentioned technical teaching is that the air passing through the heat exchanger has a higher temperature than the pure fresh air sucked in due to the mixed heated air extracted from this area of the internal combustion engine, which reduces the heat output from the cooling medium to the air at the heat exchanger and thus reduces its effectiveness.

[0013] A further disadvantage of the technology teaching mentioned is that a fan operating in a squeezing manner is less efficient than a fan operating in a suction manner with the same power, and other disadvantages are that the air moving towards the internal combustion engine especially in a squeezing manner flows along an almost uncontrolled and unpredictable flow path on the pressure side and exits into the external environment at arbitrary and usually unfavorable locations at the surface processing machine.

[0014] Another surface processing machine configured as a drilling device is known from EP 3 081 421 B1, in which the internal combustion engine as a heat source and the heat exchanger assembly are arranged on the suction side of the fan assembly, specifically arranged successively in the air flow generated by the fan assembly. Thus, the fan assembly conveys the air heated by the internal combustion engine through the heat exchanger assembly, which causes the above-mentioned disadvantages. Due to the sequential arrangement, the internal combustion engine is in an environment with a significantly low pressure relative to the atmospheric environment during the entire operation of the fan. As a result, pollutants above the average level are almost continuously conveyed from the dust-loaded construction site environment of the known surface processing machine to the internal combustion engine. The fan assembly known from EP 3 081 421 B1 is arranged inclined with respect to the longitudinal axis of the fan passage that bears it, so as to be able to achieve the largest possible fan area given the cross-section of the passage. Summary of the Invention

[0015] Therefore, the object of the present invention is to improve the surface processing machine described at the beginning while eliminating the aforementioned disadvantages.

[0016] The present invention achieves this object on the surface processing machine described at the beginning in such a way that the heat exchanger assembly and the ventilation volume of the ventilation air flow flowing away from the power source are arranged on the suction side of the fan assembly, wherein the ventilation volume is arranged downstream of the heat exchanger assembly with respect to the cooling air flow, such that the ventilation air flow generated by the fan assembly meets the cooling air flow downstream of the heat exchanger assembly and upstream of the fan assembly.

[0017] By using the arrangement of the heat exchanger assembly, the fan assembly and the ventilation volume according to the present invention, on the one hand, the fan assembly operates in a suction manner, which is not only the most efficient operation mode of the fan assembly, but also ensures fixed feasibility, in which the air heated by the heat exchanger assembly or / and by the power source can be blown away from the surface processing machine.

[0018] On the other hand, the ventilation air flow that is sucked away from the ventilation volume of the power source and heated by the power source whose temperature inevitably increases during operation meets the cooling air flow only after the cooling air flow has passed through the heat exchanger assembly. Thus, an air flow that is as cooled as possible passes through the heat exchanger assembly, and this air flow achieves a higher convective heat discharge from the heat exchanger assembly than in the case of mixing the heated ventilation air flow, based on the higher temperature difference between the cooling medium flowing through the heat exchanger assembly and the passing air flow.

[0019] The power source is also efficiently ventilated because the area around the power source, i.e., the ventilation volume that at least adjoins the power source and preferably at least partially surrounds the power source, is not circulated by air that has been previously heated by heat transfer from the heat exchanger assembly to the air.

[0020] Therefore, the heat exchanger assembly can operate effectively, and it can always effectively ventilate the power source that gets hot during operation.

[0021] Another advantage of the present invention is that only a part of the total air volume in the ventilation volume conveyed only by the ventilation fan assembly is sucked in near the power source, whereby the low pressure in the surrounding environment of the power source and the pollutants introduced into the environment are reduced compared to the prior art EP 3 081 421 B1.

[0022] Preferably, the starting points of the cooling air flow and the ventilation air flow are the external environment and the ambient atmosphere of the floor processing machine, and neither air flow absorbs heat convectively from another functional device before reaching the heat exchanger assembly or the power source. In all cases, the air sucked away by the ventilation fan assembly flows from the external environment to the heat exchanger assembly or the power source through the cover of the heat exchanger assembly and / or the cover of the power source.

[0023] The power source is preferably an internal combustion engine, and a diesel internal combustion engine is preferably used as the internal combustion engine. The diesel internal combustion engine can operate smoothly with high efficiency and low emissions. However, it is not excluded that a gasoline engine or other types of heat engines or electric motors are used as the power source, or the power source includes one or more fuel cells. The power source can in particular be an internal combustion engine with a turbocharger. The power source is also a power station carried by the surface processing machine, which provides the power required for the operation of the surface processing machine. In the case where a heat engine is used as the power source, the surface processing machine can include one or more power converters in a known manner, which convert the power source in the form of the provided power into power provided in other forms. Thus, for example, the working device can be mechanically driven through the mechanical output element of the power source, such as the crankshaft, in the case of an intermediate connecting transmission mechanism, to perform surface processing. For example, the hydraulic pump can also be operated via such a transmission mechanism, in particular the secondary drive shaft of the pump distributor transmission mechanism, and the hydraulic pump converts the power provided by the power source into potential energy in the form of a higher pressure level of hydraulic oil. The power of the power source can also be converted from mechanical power into electrical power via a generator.

[0024] According to the more general teachings of the present invention, instead of the power source, a heat source can be arranged separately from the heat exchanger assembly, in particular with a spacing therefrom, and the ventilator assembly generates a ventilation air flow in operation in a manner of drawing away from the heat source to ventilate the heat source. This applies, for example, to a heat source that can be an electrical energy storage assembly or a transmission mechanism described in the present application with respect to the power source.

[0025] The working device for surface processing is preferably a working device for stripping the surface. Here, a rotating working device with a cutting edge having a specific geometric structure, such as a milling roller, and / or a rotating working device with a cutting edge having an uncertain geometric structure, such as a so-called "grinding roller" for specifically texturing the surface, is preferred.

[0026] The cooling air flow "passing through" the heat exchanger assembly means that in the case where heat is removed from the heat exchanger assembly by the cooling air flow in a convective manner, the cooling air flow flows through the heat exchanger assembly in any manner. When passing through the heat exchanger assembly, the cooling air flow can flow along the heat transfer surface of the heat exchanger assembly in a co-current or counter-current manner in the same or opposite direction as the cooling medium flowing on the other side of the heat transfer surface. Preferably, the heat exchanger assembly is a cross-flow heat exchanger assembly, in which the cooling air flow flows transversely to the flow direction of the cooling medium flowing through the heat exchanger assembly. The heat exchanger assembly can have a cooling channel for guiding the cooling air flow, which is used to allow the cooling air flow to flow through.

[0027] It is conceivable in principle that the cooling air flow (on the one hand) and the ventilation air flow (on the other hand) are drawn in separately from each other through the fan assembly and blown into the external environment after passing through the fan assembly. However, the separate sequence of the two air flows requires the establishment of corresponding flow channels, which, when the cooling air flow should always be able to flow through the entire heat exchanger assembly, results in higher costs and leads to complex flow guidance. The higher costs and higher complexity increase the susceptibility to failure. Therefore, it is preferred to provide a mixing volume between the heat exchanger assembly and the fan assembly, in which the cooling air flow and the ventilation air flow are mixed. At the time point when the cooling air flow and the ventilation air flow are mixed, they have already served their heat dissipation purpose as convective air flows and there is no need to worry about damaging the efficiency. They are jointly and mixedly conveyed as exhaust air through the fan assembly to its pressure side and preferably blown into the external environment.

[0028] It is conceivable to filter the exhaust air upstream or downstream of the fan assembly, i.e., to arrange an air filter through which the exhaust air flows along the flow path of the exhaust air. Since usually only air is drawn in from the external environment and conveyed as a cooling air flow through the heat exchanger or only air is drawn away from the area of the power source, and for the power source the flowing air is usually replenished from the external environment, the degree of contamination of the two air flows remains within limits, such that there is no need to filter the air flow either to protect the generally stable fan assembly or to clean the exhaust air.

[0029] To simplify the installation of the floor processing machine, the floor processing machine, in particular its cooling device, may have a pre-installed air flow assembly, wherein the air flow assembly has a fan assembly, a heat exchanger assembly, and a frame that bears the fan assembly and the heat exchanger assembly. The air flow assembly can be simply pre-installed at a separate installation location and fixed as a pre-installed assembly on the floor processing machine, in particular on its frame.

[0030] The frame can be a truss with multiple rods, and the fan assembly and the heat exchanger assembly are held on the rods. The skeletal truss has a relatively small weight. Due to the limited flow conditions, the frame can have a shell section that at least partially surrounds the mixing volume. For this purpose, the frame can have a frame skin and can be formed, for example, at least partially from sheet metal or / and plastic surfaces. Thus, it can be ensured that the cooling air flow that actually only or mainly passes through the heat exchanger assembly through the fan assembly and the ventilation air flow drawn away from the power source, but no secondary air is drawn in from other areas of the floor processing machine. Thus, it can be prevented that the fan assembly draws in air from areas of the floor processing machine that do not require convective cooling or / and exhaust.

[0031] In order to enable the cooling air flow and the ventilation air flow to meet and preferably mix with each other upstream of the fan assembly and downstream of the heat exchanger assembly, it is advantageous for the fan assembly and the heat exchanger assembly to be arranged at a distance from each other. When the fan assembly and the heat exchanger assembly are arranged to move relative to each other rotatably about a swing axis, particularly good space utilization is achieved at this time. At this time, different regions of the fan assembly (on the one hand) and the heat exchanger assembly (on the other hand) have different distances from each other. For this purpose, the flow path from the heat exchanger assembly to the fan assembly is short. Additionally or alternatively, the fan assembly and the heat exchanger assembly can be arranged to be translatably movable along a movement axis. However, the translational movement of the heat exchanger assembly and the fan assembly generally requires more installation space than the rotational movement.

[0032] In order to advantageously reduce the requirement for installation space, the fan assembly is preferably a substantially flat fan assembly. Here, "flat" cannot be understood strictly mathematically, but rather the fan assembly has significantly larger dimensions in two mutually orthogonal spatial directions than in a third spatial direction orthogonal to the said spatial directions, and the third direction is particularly preferably the flow-through direction of the fan assembly, and the discharge air flows through the fan assembly along this flow-through direction. Preferably, the rotation axis of at least one fan of the fan assembly extends along the third spatial direction, and preferably, if the fan assembly includes a plurality of fans, the rotation axes of all the fans extend along the third spatial direction. Alternatively or preferably additionally, the heat exchanger assembly is also a substantially flat heat exchanger assembly. This also means that the heat exchanger assembly has significantly larger dimensions in two mutually orthogonal spatial directions respectively than in a third spatial direction orthogonal to the two spatial directions, and this third direction is preferably the flow-through direction along which the cooling air flow flows through the heat exchanger assembly which is preferably configured as a cross-flow heat exchanger assembly.

[0033] When both the heat exchanger assembly and the fan assembly are configured as flat assemblies, at this time, preferably, the swing axis about which the two assemblies move relative to each other rotatably is parallel to the construction plane of each of the two assemblies.

[0034] The flow-through surface of the heat exchanger assembly is preferably larger than the flow-through surface of the fan assembly, so that as large a heat transfer surface as possible can be provided on the heat exchanger assembly. The flow-through surface of the fan of the fan assembly is preferably circular or annular, whereby this surface can approach the rotating fan wheel as closely as possible. If the fan assembly has a plurality of fans, preferably the flow-through surface of each fan is circular or annular.

[0035] In order to utilize as well as possible the installation space provided for installing the heat exchanger assembly, the flow-through surface of the heat exchanger assembly is preferably rectangular.

[0036] When the fan assembly and the heat exchanger assembly are arranged to move relative to each other rotatably about a swing axis, the rotational displacement angle is preferably between 65° and 115°, particularly preferably between 80° and 100°. Thus, by angling the two assemblies relative to each other by a displacement angle within a right-angle range, the heat exchanger assembly and the fan assembly, each having a relatively large flow-through surface, can be arranged on a relatively small base surface. The above air flow assembly may have a generally rhomboid shape, for example, having a mixed volume including a substantially triangular basic shape, wherein the mixed volume may be formed along one side by the fan assembly, along a second side by the heat exchanger assembly, and along a third side by the wall of the frame forming the shell section.

[0037] When the ventilation air flow flows towards the mixed volume transversely to the flow direction of the cooling air flow passing through the heat exchanger assembly and / or transversely to the exhaust air flow passing through the fan assembly, the fan assembly and the heat exchanger assembly can be very compact in space at this time, especially arranged on the floor processing machine as a very compact air flow assembly. Thus, in the case of the generally rhomboid air flow assembly described above by way of example, the two air flows, preferably the cooling air flow and the exhaust air flow, can flow through the outer side surfaces of the generally rhomboid air flow assembly, and the air flow, preferably the ventilation air flow, flows through one end surface of the generally rhomboid air flow assembly.

[0038] For example, the shell section of the frame that at least partially surrounds the mixed volume may have through holes spaced from the heat exchanger assembly and the fan assembly, and the through holes can be flowed through by the ventilation air flow. As described above, the shell section preferably having through holes is part of the end wall of the rhomboid air flow assembly.

[0039] In principle, the through hole may have an unchangeable cross-section, and the shape and / or size and / or position of the cross-section can be optimized through corresponding tests. However, it is also conceivable that, in order to adjust the ventilation of the power source, for example, according to the operating state of the power source, the cross-section through which the ventilation air flow of the through hole can flow is designed to be variable, so as to change the amount of ventilation air flowing in the ventilation air flow per unit time under given operating conditions. For this purpose, for example, the through hole may have a partition device, and by means of the partition device, the coincidence degree of the through hole passing through the partition member can be actuated by displacing the partition member relative to the member forming the through hole. When the through hole is formed on the shell section of the frame of the air flow assembly, preferably the partition device, especially the partition member capable of moving relative to the through hole, is also accommodated on the frame of the air flow assembly, especially on the shell section of the frame.

[0040] When the surface processing machine is operating, the amount of cooling air required per time unit is generally greater than, and even usually significantly greater than, the amount of ventilation air required in the same time unit. Most of the air volume conveyed by the ventilation fan assembly flows through the heat exchanger assembly. The ventilation air flow is mostly only used to ventilate the power source to avoid heat accumulation in the environment. The cooling air flow is usually used to specifically remove heat to maintain thermal balance in at least one functional device cooled by the heat exchanger assembly during the operation of the surface processing machine.

[0041] The heat exchanger assembly may have multiple heat exchangers, which are preferably components of different cooling circuits and / or cooling passages for cooling functional devices on the surface processing machine. Advantageously, the corresponding cooling media of different cooling circuits and / or cooling passages can be cooled in a convective manner at one and the same location. For example, one cooling circuit may extend between the heat exchanger and the power source, one cooling circuit may extend between the heat exchanger and the hydraulic oil tank, or the heat exchanger may be traversed by hydraulic oil as the cooling medium for outputting heat as an oil cooler. In one cooling circuit, the heat exchanger can be used as a gas-gas-charged air cooler for a turbocharger. In one cooling circuit, the heat exchanger can be part of a gas-liquid-charged air cooler for a turbocharger. The heat exchanger in one cooling circuit can also be a transmission oil cooler. Thus, different heat exchangers can be traversed by different cooling media. Two or more heat exchangers can also be traversed by the same cooling medium, but the cooling medium circulates in separate cooling circuits and / or passes through separate cooling passages.

[0042] The ventilation fan assembly may also have multiple ventilation fans to generate air flows of different intensities in different areas of the ventilation fan assembly and especially the mixing volume if necessary. This can be advantageous when one of the multiple heat exchangers requires a higher convective cooling power than the other heat exchangers in the heat exchanger assembly. Preferably, the ventilation fans of the ventilation fan assembly can be controlled separately from each other so that different amounts of air flow can be generated simultaneously by each ventilation fan.

[0043] The surface processing machine preferably has a driver's cab, and the operation of the surface processing machine can be controlled by the driver's cab, specifically whether it is the main driving operation without surface processing or the main processing operation with only a small driving power. The heat exchanger assembly and the ventilation fan assembly can be arranged between the driver's cab and the longitudinal end at the front of the surface processing machine, so that the foregoing advantageous cooling device can also be installed on a compact milling machine, the working device of which is configured such that the milling rollers are arranged in the area at the rear of the surface processing machine, especially under and / or behind the driver's cab.

[0044] In principle, it is conceivable that a ventilation duct for guiding the ventilation air flow is laid from the power source to the cooling device. This ventilation duct delimits a part of the ventilation volume. However, this generally means an increase in the flow resistance of the ventilation air flow and additional installation costs. Therefore, preferably, the heat exchanger assembly and the fan assembly are arranged adjacent to the power source. Particularly preferably, there are no other functional devices between the power source and the cooling device, especially the air flow assembly, so that the fan assembly can directly draw air from the ventilation volume that serves as the ventilation air flow. According to this preferred design, the ventilation volume can, on the one hand, adjoin the power source, even at least partially surround the power source, without forming a channel-shaped duct, and on the other hand, the ventilation volume can adjoin the through-hole of the mixing volume.

[0045] In order to avoid affecting the mechanical driver on the driver's cab behind the power source in the forward driving direction, it is preferred that the heat exchanger assembly is machined close to one side of the ground processing machine in the machine transverse direction, and the fan assembly is close to the other side opposite to the machine transverse direction. Thereby, in particular, the exhaust air flow can be blown away from the side of the ground processing machine by the flow component in the machine transverse direction. At this time, the driver's cab does not pass through the exhaust air flow when driving forward.

[0046] In order to better view the ground processing, the driver's cab is preferably arranged laterally, that is, offset relative to the longitudinal central axis of the machine in the machine transverse direction. In order to avoid loading the driver's cab with the exhaust air flow, its discharge location is preferably close to, particularly preferably on the side of the ground processing machine on both sides that is offset from the driver's cab. In other words, it is preferred that the discharge location is close to, especially on the side of the ground processing machine on both sides that is farther from the driver's cab.

[0047] Preferably, the components that are rotationally displaced relative to each other: the fan assembly and the heat exchanger assembly can form a ridge, and the ridge line preferably extends parallel to the machine longitudinal axis as well.

[0048] In other words, it is possible to avoid loading the driver's cab due to the operation of the cooling device in such a way that the cooling air flow passing through the heat exchanger assembly has a flow component in the machine transverse direction and a flow component in the machine height direction, or / and the exhaust air flow passing through the fan assembly has a flow component in the machine transverse direction and a flow component in the machine height direction. Based on the above-mentioned preferred arrangement of the heat exchanger assembly and the fan assembly forming a ridge, especially through the generally rhomboid configuration of the above-mentioned air flow assembly, it can be achieved that the flow components extending in the machine height direction of the cooling air flow (on the one hand) and the exhaust air flow (on the other hand) are preferably arranged oppositely. And the flow components in the machine transverse direction are preferably arranged in the same direction. At this time, the ventilation air flow preferably flows into the mixing volume of the cooling device along the machine longitudinal axis.

[0049] To prevent external influences, the heat exchanger assembly and / or the ventilator assembly and / or the power source may be covered by a cover. The cover preferably has an opening to ensure that ambient air comes into contact with the cooling device and / or the power source.

[0050] In the ready-to-run state of the surface working machine, the separating device can be abutted against the side of the heat exchanger assembly facing the cover of the heat exchanger assembly. The separating device separates the flow path from the perforable opening in the cover to the heat exchanger assembly from the surroundings of the flow path in at least one direction transverse to the flow path. The separating device preferably extends from the cover directly to the heat exchanger assembly. Preferably, the separating device is a closed shaft wall surrounding the flow path, which separates the well serving as the flow path or flow channel surrounded by it from the surroundings outside the shaft wall. Thereby, it can be substantially ensured that only ambient air from the external environment of the surface working machine is drawn in as a cooling air flow upstream of the heat exchanger assembly.

[0051] The separating device is preferably connected to the cover for common movement, and by means of the cover, the separating device can also be moved away from the cooling device, and the cooling device, especially the heat exchanger assembly shielded from excess air by the separating device during operation, can be accessed with a small amount of operation.

[0052] The separating device can be abutted against the side of the heat exchanger assembly facing the cover with a sealing assembly, such as an elastomeric seal surrounding the flow path, arranged in between. The sealing assembly can be foam, open-cell or closed-cell or solid.

[0053] The side of the heat exchanger assembly facing the cover can have a abutting surface, preferably an equipment frame surrounding the surface through which the cooling air flow can pass. The separating device can preferably be abutted against the abutting surface with a sealing assembly arranged in between in the ready-to-run state of the surface working machine.

[0054] The sealing assembly can be fixedly connected to the heat exchanger assembly or to the separating device. The sealing assembly can include sub-sealing assemblies, each of which is fixedly connected to a different structure formed by the heat exchanger assembly and the separating device.

[0055] In order to be able to mix the cooling air flow and the ventilation air flow well and thus enable the ventilator assembly to be evenly thermally loaded by the exhaust air passing through it, the mixing volume is preferably larger than the volume occupied by the heat exchanger assembly. Since the structure of the heat exchanger assembly is usually complex, the volume surrounded by the envelope surface surrounding the heat exchanger assembly in contact is sufficient to determine its volume.

[0056] Regarding the actually perforable volume of the cooling air flow through the heat exchanger assembly, the mixing volume preferably has at least twice, particularly preferably at least three times, the perforable volume of the heat exchanger assembly, so that the cooling air flow can be fully mixed with the ventilation air flow after passing through the heat exchanger assembly.

[0057] For cleaning the cooling device, the fan assembly can be configured such that, for a temporary cleaning operation, the direction of rotation of at least one fan, preferably all fans, is temporarily reversed relative to normal cooling operation. During the cleaning operation, the fan assembly conveys air through the fan assembly into the mixing volume. Thus, the fan assembly can keep the heat exchanger assembly and / or the cover of the heat exchanger assembly free of dust and other contaminants during the cleaning operation, which contaminants especially deposit on the side of the heat exchanger assembly facing the external environment of the floor processing machine.

[0058] When a closable through-hole is provided between the mixing volume and the ventilation volume as described above, the cleaning air flow flowing through the fan assembly in a direction opposite to the exhaust air flow generated during the cleaning operation can be utilized particularly effectively. When the through-hole is closed, at this time, all the cleaning air flow is guided through the heat exchanger assembly and cleans it.

[0059] The above applies to the prescribed cooling operation implemented during the floor processing operation or the driving operation of the cooling device: the fan assembly generates a cooling air flow and a ventilation air flow, which flow towards the fan assembly and the fan assembly blows away the cooling air flow and the ventilation air flow as an exhaust air flow.

[0060] While preferably the geothermal heat exchanger assembly is the only heat transfer device through which the cooling air stream passes and the power source, if necessary, and additional equipment arranged thereon (such as a turbocharger) are the only heat sources for the ventilation air stream drawn in from its surroundings, in principle it is not excluded that the cooling air stream passes through another heat transfer device after passing through the heat exchanger assembly and / or the ventilation air stream passes through another heat transfer device after being sufficiently far away from the power source and absorbs heat therefrom. It is important that the air that must still pass through the heat exchanger assembly and / or flow into the surroundings of the power source and release heat to the power source or prevent heat transfer from the power source to the air surrounding the power source is not heated by this other heat transfer device as well. That is, the object of the present invention is that ambient air without additional heating passes through the heat exchanger assembly and that ambient air without additional heating ventilates the power source. Inevitable heat sources, such as the heated covers or enclosed channels of a surface working machine by ambient air, are not considered here. Thus, for example, another heat transfer device through which the cooled air stream and / or the ventilated air stream passes can be arranged with respect to the cooling air stream downstream of the heat exchanger assembly, such as arranged in a mixing volume. Additionally or alternatively, another heat transfer device through which the cooled air stream and / or the ventilated air stream passes can be arranged with respect to the ventilated air stream downstream of the power source, such as arranged in a mixing volume, in a through-hole, or immediately before or after the through-hole. The through-hole can be an inlet partition or an outlet partition of another heat transfer device. The arrangement of the other heat transfer device in the ventilated air stream does not change: the ventilated air stream meets the cooling air stream as described downstream of the heat exchanger group and upstream of the ventilator assembly. The other heat transfer device can be flowed through by a heat-transfer medium outputting heat as an active heat transfer device or can be a heat-conducting cooling body that is thermally connected to the component to be cooled conductively. Description of the Drawings

[0061] The present invention will be described in detail below with reference to the drawings. Shown therein are:

[0062] Figure 1 A perspective view of a compact milling machine seen from the rear-oblique side is shown,

[0063] Figure 2 showing the Figure 1 compact milling machine without a cover

[0064] Figure 3 in a perspective view, Figure 1 and Figure 2 a perspective view of the air flow assembly of the cooling device of the compact milling machine, and

[0065] Figure 4 also shown is Figure 3 a side view of the air flow assembly. Detailed Description of the Embodiment

[0066] Figure 1 andFigure 2 Figure 1 shows a cold milling machine for road surfaces, which is exemplarily designed as a compact milling machine and is shown in perspective from the rear - diagonal. It is generally designated by "10". In the specifically shown compact milling machine, the working device 12 is located in the milling drum housing 14 in the rear region of the cold milling machine for road surfaces. For example, it is located below the driver's cab 16, which is arranged asymmetrically offset to the right of the machine along the forward driving direction. The driver's cab can be reached via a ladder 17 at the rear of the machine, and the cold milling machine for road surfaces can be controlled by the machine driver from the driver's cab. At the rear of the cold milling machine for road surfaces, a scraper cover 14a can be seen, which can be lifted and lowered via a piston - cylinder actuator 15. The scraper cover forms the rear wall of the milling drum housing 14.

[0067] The machine driver can sit on the driver's seat 20 to operate the operating console 18 and is simultaneously protected from precipitation and solar radiation by a protective hood 22 that can be displaced along the machine height axis H of the cold milling machine for road surfaces.

[0068] The cold milling machine for road surfaces stands on a foundation U, which is shown symbolically in Figure 1 for the sake of clarity. In the shown example, the traveling gear 24 includes four chain - type traveling mechanisms 26. The foundation U can be processed in a stripping manner by the working device 12. Instead of chain - type traveling mechanisms 26, wheel - type traveling mechanisms can also be provided. Whether it is a chain or a wheel, in any case, the circumferential axis around which the corresponding traveling mechanism is structured extends parallel to the surface of the foundation U, so that the traveling mechanism, here the chain - type traveling mechanism 26, can roll on the foundation U during the traveling operation of the cold milling machine for road surfaces. Figure 1 In Figure 1, the working device 12, which is a milling drum accommodated in the milling drum housing 14 in the shown application example, can strip materials from the ground to be processed. The working device rotates around a rotational axis parallel to the machine transverse direction Q. The traveling gear having deflectable chain - type traveling mechanisms 26, which are each individually driven by a hydraulic motor 25 in the shown embodiment, is used to drive the cold milling machine for road surfaces and is thus used, in particular, to advance the working device 12 during the stripping ground processing.

[0069] The traveling gear 24 has a frame 30 (see

[0070] Figure 1), which can change its height, i.e., can be displaced along the machine height axis H, via a lifting column 28. The frame bears the functional devices of the cold milling machine for road surfaces. The functional devices include the aforementioned working device 12 together with the milling drum housing 14, the operating console 18, the hydraulic motor 25, a diesel internal combustion engine (see Figure 2 Figure 1) as the power source 32 in the preface of the specification, a cooling device 34 (see Figure 2 Figure 1), a cover 36, just to mention some examples of the functional devices. Figure 2 Figure 1), a cover 36, just to mention some examples of the functional devices.

[0071] The internal combustion engine is surrounded by a ventilation volume 32a filled with air, and the air in the ventilation volume is heated by the internal combustion engine based on convection and radiation during the operation of the internal combustion engine.

[0072] In Figure 1 there are an intake port area 38 and an exhaust port area 40 constructed on the hood 36. The hood 36 is penetrated by openings in the intake port area and the exhaust port area so that air can pass between the outer side and the opposite inner side of the hood 36. Through the opening of the intake port area 38, the cooling device 34 can suck in air from the external environment of the road milling machine, and the cooling device conveys the air back to the external environment of the road milling machine again through the opening of the exhaust port area 40 after the air passes through the cooling device 34. Intake or the intake port area 38 is mainly located on the upper side of the hood 36 and on the mechanical right side in its forward travel direction V. Exhaust or the exhaust port area 40 is mainly, or even entirely, located on the mechanical left side in the mechanical transverse direction Q opposite thereto and in the forward travel direction V.

[0073] It should only be noted for the sake of understanding that on the front side of the road milling machine opposite to the mechanical rear in the mechanical longitudinal direction L, there is a support configuration 42 carried by the frame 30, and the support configuration is used to support a material transport device (not shown but present during ground processing) for loading milled material, especially a conveyor belt.

[0074] As can be seen when removing the hood 36 as in Figure 2 the cooling device 34 configured as a pre-installed air flow assembly 44 includes a heat exchange assembly 46 and a fan assembly 48 having two exemplary fans 48a and 48b arranged side by side with each other. The fan assembly 48 can have only one fan or more than two fans different from the shown example, and multiple fans can be arranged in different spatial relationships with each other, such as being stacked or diagonally staggered with each other.

[0075] The heat exchange assembly 46 also has a first heat exchanger 46a through which the cooling medium of the internal combustion engine flows so as to output the heat previously contained in the internal combustion engine to the air passing through the heat exchanger 46a in the heat exchanger 46a. The heat exchange assembly 46 also has a second heat exchanger 46b which serves as an intercooler for the boost air of the turbocharger 50 cooperating with the internal combustion engine. That is, the cooling medium flowing through the heat exchanger 46a is liquid, while the cooling medium flowing through the heat exchanger 46b is gaseous. The heat exchange assembly 46 can have more or fewer heat exchangers 46a and 46b than the two shown. For example, another heat exchanger in the heat exchange assembly 46 can be used as a hydraulic oil cooler and is flowed through by the hydraulic oil flowing through the hydraulic motor 25 as the cooling medium. Thereby, the hydraulic motor 25 can also be cooled by means of the hydraulic oil.

[0076] The two heat exchangers 46a and 46b can be arranged relative to one another in a spatial relationship different from that shown, i.e., for example, side by side along the mechanical longitudinal axis L instead of in the sequence shown. Instead of a gas-gas charge air cooler, the heat exchanger assembly 46 can have a gas-liquid heat exchanger as part of the charge air cooling system, where, in this case, the charge air transfers heat to a liquid cooling medium which outputs the heat to the air passing through the heat exchanger assembly 46.

[0077] It can be seen in Figure 2 the first coolant line 52a which conveys the liquid coolant of the internal combustion engine to the heat exchanger 46a and the second coolant line 52b which conveys the gaseous coolant to the heat exchanger 46b.

[0078] The air flow assembly 44 is directly supported on the frame 30 via a plurality of, in the example shown a total of four, frame-fixed support configurations 54.

[0079] The following refers to Figure 3 for a detailed description of the air flow assembly 44.

[0080] The air flow assembly 44 is fixed to the support configuration 54 of the frame 30 via a total of four paired support configurations 56, only three of which are visible in Figure 3 The paired support configurations 56 are fixed, for example by welding, to a frame 58 made of a sheet material, for example a sheet. The frame 58 carries the heat exchanger assembly 46 as well as the fan assembly 48.

[0081] In Figure 3 the inlet interface 47a through which the coolant enters the heat exchanger 46a can also be seen. The return interface 47b after the coolant has passed through the heat exchanger 46a is located on the opposite side of the heat exchanger 46a and is not visible in Figure 3 but is visible in Figure 4 The inlet interface 53a through which the charge air enters the heat exchanger 46b and the return interface 53b after the charge air has passed through the heat exchanger 46b can also be seen in

[0082] In Figure 3 The shell-shaped frame 58 surrounds the mixing volume 60 between the heat exchanger assembly 46 and the fan assembly 48 with a shell section 59. The pre-mounted air flow assembly 44 has a substantially rhomboid shape with a substantially triangular base surface. Two sides of the triangular prism are formed by the heat exchanger assembly 46 and by the fan assembly 48. The third side forms the underside of the shell section 59 and thus forms a boundary wall of the mixing volume 60. On the side of the shell section 59 of the frame 58 pointing towards

[0083] and Figure 3 and Figure 4In the observer's end side, a through hole 62 is constructed, and through the through hole, contact can be made with the mixing volume 60 from the outside, specifically, as shown in Figure 2 from the surroundings of the internal combustion engine, more specifically, from the ventilation volume 32a.

[0084] The through hole 62 is constructed in the flat plate 64 mounted on the remaining end side of the housing section 59. The flat plate covers the through opening that penetrates the end side of the load-bearing flat plate 64 of the housing section 59. In this way, a through opening can be provided, which also serves as the original through hole with the largest passage cross-section. The through opening can be matched to the corresponding application situation of the specific floor processing machine by arranging the flat plate 64 with the through hole 62 that is optimal in terms of shape, position, and passage cross-section for the corresponding application situation.

[0085] In the illustrated embodiment, the through hole 62 is formed by a plurality of small basic openings, for example, implemented as basic openings smaller than the holes penetrating the flat plate 64, and all these basic openings together form the through hole 62. In addition, the through hole 62 is constructed in the flat plate 64 closer to one corner than to the other three corners, so as to suck the ventilation air flow from the area around the internal combustion engine's ventilation volume 32a that is as optimal as possible for this purpose. The through hole 62 can be formed by a single opening or a smaller number of openings differently from the illustration. The through hole can also be constructed at other positions in the flat plate 64.

[0086] As can also be seen in Figure 3 , the two ventilators 48a and 48b are substantially the same and are arranged with parallel rotation axes Ra and Rb. The ventilator wheels of the ventilators 48a and 48b are preferably driven hydraulically or electrically, and more preferably, each of the ventilators 48a and 48b can be controlled or adjusted separately from the other.

[0087] In Figure 4 , in the top view of the end face of the housing section 59 looking at the frame 58, it can be clearly seen that the heat exchanger assembly 46 is arranged as a flat heat exchanger assembly substantially in the heat exchanger plane WE orthogonal to the drawing plane of Figure 4 , and the ventilator assembly 48 is arranged as a flat ventilator assembly substantially in the ventilator plane LE that is also orthogonal to the drawing plane of Figure 4 . In the illustrated example, the heat exchanger plane WE and the ventilator plane LE enclose an angle between 100° and 110°. They swing relative to each other about the swing axis SA orthogonal to the drawing plane of Figure 4 and form a ridge F with a ridge line parallel to the swing axis SA and the mechanical longitudinal axis L. Here, the ridge F is formed by the highest edge of the equipment frame 74 along the mechanical height direction H. The equipment frame 74 surrounds the surface through which the cooling air flow KL for heat transfer of the heat exchanger assembly 46 can flow. In the illustrated example, the equipment frame 74 completely and enclosingly surrounds the flowable surface of the heat exchanger assembly 46.

[0088] The heat exchanger plane WE and the fan plane LE are not planes that are infinitely thin in the mathematical sense here, but rather component planes that have significantly smaller dimensions in their respective thickness directions than in two extension directions that are orthogonal to the thickness direction and orthogonal to each other.

[0089] Unlike Figure 3 in, Figure 4 the through hole 62' constructed in the flat plate 64 in is configured as the only relevant through hole 62', but this through hole is not covered by the partition 68 that can move along two tracks 66. The partition 68 itself has a partition hole 70 therethrough, and the partition hole can be made to coincide with the through hole 62' by moving the partition 68 along the tracks 66. Thereby, the flowable cross-section of the through hole 62' can be changed. The partition 68 can be moved between a locking position in which the partition 68 shown completely closes the through hole 62' and an open position in which the partition hole 70 coincides completely with the through hole 62' by an actuator 72. Preferably, it can travel to an intermediate position. However, it can also be arranged such that the through hole 62' can only be completely opened or completely closed by the movement of the partition 68. Figure 4 The partition 68 shown in can be moved between a locking position in which the through hole 62' is completely closed and an open position in which the partition hole 70 coincides completely with the through hole 62'. Preferably, it can travel to an intermediate position. However, it can also be arranged such that the through hole 62' can only be completely opened or completely closed by the movement of the partition 68.

[0090] The fan assembly 48 is arranged on the cooling device 34 or on the air flow assembly 44 such that the heat exchanger assembly 46 and the through hole 62 or 62' are located on the suction side of the fan assembly 48. Therefore, by operating the fan assembly 48, a low pressure is generated on the suction side of the fan assembly 48 relative to the ambient atmosphere, which causes the cooling air flow KL to enter the mixing volume 60 from the outside through the heat exchanger assembly 46. When the through hole 62 or 62' is open, the low pressure also generates a ventilation air flow LL that enters the mixing volume 60 from the outside through the through hole 62 or 62' and is orthogonal to the drawing plane of Figure 4 . Here, the cooling air flow KL and the ventilation air flow LL from this area of the internal combustion engine can be mixed. The pressure difference generated by the fan assembly 48 between its suction side and its pressure side also causes an exhaust air flow AL to be discharged from the mixing volume 60 through the fan assembly 48.

[0091] The flow directions of the cooling air flow KL and the exhaust air flow AL shown by corresponding arrows corresponding to the respective thickness directions of the flowing-through components are preferably located in a plane. And the inclination of this plane relative to the mechanical longitudinal direction L is preferably between 75° and 105°, especially orthogonal thereto. The flow direction of the ventilation air flow LL through the through hole 62 or 62' extends in a plane that is transverse to the plane in which the flow directions of the cooling air flow KL or the exhaust air flow AL are developed, especially orthogonally thereto.

[0092] This ensures that no air that has previously been heated by the heat absorbed on the heat exchanger assembly 46 reaches the area of the internal combustion engine and further heats the environment surrounding the internal combustion engine or prevents its cooling. It is also ensured that no air heated by the internal combustion engine flows through the heat exchanger assembly 46 and thereby reduces the convective cooling effect of the cooling medium flowing through the heat exchanger assembly 46.

[0093] In Figure 3 and Figure 4 the well wall 76 is shown in dashed lines as a separating device that extends from the cover 36 to the heat exchanger assembly 46 in the state in which the surface processing machine 10 is ready to operate. Figure 4 The arrow KL in

[0094] also symbolizes a flow path along which the cooling air flow KL flows from the opening 38 in the cover 36 to the heat exchanger assembly 46 and continues to flow through the heat exchanger assembly. This flow path is located within the well wall 76 in a flow channel defined by the well wall 76 and bounded by its external environment. The well wall 76 preferably has a mating equipment frame 78 at its longitudinal end facing the heat exchanger assembly 46, and the mating equipment frame faces the equipment frame 74 with a seal 80 arranged in the middle in the state in which the surface processing machine 10 is ready to operate. The seal 80, which is preferably an elastomer, can be fixedly connected to the equipment frame or to the well wall 76, in particular to the mating equipment frame 78.

Claims

1. A self-propelled surface processing machine (10), the surface processing machine comprising: - A traveling mechanism (24) by means of which the surface processing machine (10) can be roll-erected on a foundation (U), and - A frame (30) carried by the traveling mechanism (24), - A power source (32) accommodated on the frame (30), the power source being used to provide power that can be used to make the surface processing machine (10) travel or / and perform surface processing operations, - A working device (12) for surface processing accommodated on the frame (30), - A cooling device (34) for cooling at least one functional device of the surface processing machine (10), wherein the cooling device (34) includes a pre-installed air flow assembly (44), and wherein the air flow assembly (44) is fixed to the frame and has: - At least one heat exchanger assembly (46) including at least one heat exchanger (46a, 46b), the at least one heat exchanger being used to transfer heat from a cooling medium to air, and - A ventilator assembly (48), the ventilator assembly being configured and arranged on the one hand to generate a cooling air flow (KL) passing through the heat exchanger assembly (46) and being configured and arranged on the other hand to generate a ventilation air flow (LL) flowing away from the power source (32) in the region of the power source (32), It is characterized in that the heat exchanger assembly (46) and the ventilation volume (32a) of the ventilation air flow (LL) flowing away from the power source (32) are arranged on the suction side of the ventilator assembly (48), wherein the ventilation volume (32a) is arranged downstream of the heat exchanger assembly (46) with respect to the cooling air flow (KL), such that the ventilation air flow (LL) generated by the ventilator assembly (48) meets the cooling air flow (KL) downstream of the heat exchanger assembly (46) and upstream of the ventilator assembly (48).

2. The self-propelled surface processing machine (10) according to claim 1, characterized in that, A mixing volume (60) is provided between the heat exchanger assembly (46) and the ventilator assembly (48), and in the mixing volume, the cooling air flow (KL) and the ventilation air flow (LL) are mixed.

3. The self-propelled surface processing machine (10) according to claim 2, characterized in that, The air flow assembly (44) has a frame (58) carrying at least one ventilator (48a, 48b) and the heat exchanger assembly (46).

4. The self-propelled surface processing machine (10) according to claim 3, characterized in that, The frame (58) has a shell section (59) at least partially surrounding the mixing volume (60).

5. The self-propelled surface processing machine (10) according to claim 3 or 4, characterized in that, The ventilator assembly (48) and the heat exchanger assembly (46) are arranged to be rotatably movable relative to each other about a swing axis (SA), or to be translatably movable along a moving axis.

6. The self-propelled surface processing machine (10) according to claim 3 or 4, characterized in that, The ventilator assembly (48) is a substantially flat ventilator assembly (48); or / and the heat exchanger assembly (46) is a substantially flat heat exchanger assembly (46).

7. The self-propelled surface working machine (10) according to any one of claims 2 to 4, characterized in that, The ventilation air flow (LL) is transverse to the flow direction of the cooling air flow (KL) passing through the heat exchanger assembly (46) and / or transverse to the exhaust air flow (AL) flowing through the fan assembly (48) towards the mixing volume (60).

8. The self-propelled surface processing machine (10) according to claim 4, characterized in that, The housing section (59) of the frame (58) that at least partially encloses the mixing volume (60) has through holes (62; 62') spaced apart from the heat exchanger assembly (46) and from the fan assembly (48), and the through holes can be flowed through by the ventilation air flow (LL).

9. The self-propelled surface processing machine (10) according to claim 8, characterized in that, The cross-section through which the ventilation air flow (LL) of the through holes (62; 62') can flow is designed to be variable in order to change the amount of ventilation air flowing in the ventilation air flow (LL) per unit of time under given operating conditions.

10. The self-propelled ground working machine (10) according to any one of claims 1 to 4, characterized in that, The heat exchanger assembly (46) has a plurality of heat exchangers (46a, 46b), which are part of different cooling circuits (52a) and / or cooling passages (52b), and / or the fan assembly (48) has a plurality of fans (48a, 48b).

11. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The surface working machine (10) has a driver's cab (16), wherein the heat exchanger assembly (46) and the fan assembly (48) are arranged between the driver's cab (16) and the longitudinal end at the front of the surface working machine (10).

12. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The heat exchanger assembly (46) and the fan assembly (48) are arranged adjacent to the power source (32).

13. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The heat exchanger assembly (46) is close to one machine side, and the fan assembly (48) is close to the other machine side opposite in the machine transverse direction (Q).

14. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The cooling air flow (KL) passing through the heat exchanger assembly (46) has a flow component in the machine transverse direction (Q) and a flow component in the machine height direction (H); and / or the exhaust air flow (AL) flowing through the fan assembly (48) has a flow component in the machine transverse direction (Q) and a flow component in the machine height direction (H).

15. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The heat exchanger assembly (46) and / or the fan assembly (48) and / or the power source (32) are covered by a cover (36).

16. The self-propelled surface processing machine (10) according to any one of claims 1 to 4, characterized in that, The self-propelled surface working machine is a road milling machine, an open-pit mining machine or a stabilizer.

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