Ground processing machine

Abstract

The invention relates to a floor processing machine having two drive rollers which are arranged one behind the other in the machine longitudinal direction and which can be rotated about a respective rotational axis, each drive roller comprising two drive roller sections which are arranged one behind the other in the direction of the associated rotational axis, and having a hydraulic drive system of the drive rollers, a first hydraulic connection of the first hydraulic drive pump is or can be connected to first hydraulic connections of the first and second hydraulic drive motors via a first hydraulic line; the first liquid connection of the second hydraulic drive pump is connected or can be connected to the first liquid connections of the third and fourth hydraulic drive motors via a second hydraulic line; a second liquid connection of the first hydraulic drive pump is or can be connected to second liquid connections of the second and third hydraulic drive motors via a third hydraulic line; a second liquid connection of the second hydraulic drive pump is or can be connected to second liquid connections of the first and fourth hydraulic drive motors via a fourth hydraulic line.

Description

Technical Field

[0001] The invention relates to a ground processing machine having two drive rollers that are arranged in sequence in the longitudinal direction of the machine and are rotatable about respective rotation axes, wherein each drive roller includes two drive roller segments that are arranged in sequence in the direction of the assigned rotation axis, and having a hydraulic drive system for the drive rollers. Background Art

[0002] In order to ensure that such a ground processing machine (e.g., configured as a ground compactor) can continue to transmit torque through other drive roller segments when slipping occurs in one or more drive roller segments, it is known to use a flow divider. When excessive liquid outflow occurs through the hydraulic drive motor assigned to such a drive roller segment in the slipping state of the drive roller segment, the flow divider can block or throttle the liquid supply to the drive roller segment, and thereby maintain sufficient liquid supply to the non-slipping drive rollers. Summary of the Invention

[0003] The object of the invention is to provide a ground processing machine for which it is possible to avoid the slipping state of one or more drive roller segments by a structurally simple and energy-efficient design of the hydraulic drive system.

[0004] According to the invention, the above object is solved by a ground processing machine having two drive rollers that are arranged in sequence in the longitudinal direction of the machine and are rotatable about respective rotation axes, wherein each drive roller includes two drive roller segments that are arranged in sequence in the direction of the assigned rotation axis, and having a hydraulic drive system for the drive rollers, wherein the hydraulic drive system includes:

[0005] - a first travel - hydraulic motor, which is assigned to the first drive roller segment of the two drive rollers

[0006] thereof,

[0007] - a second travel - hydraulic motor, which is assigned to the second drive roller segment of the two drive rollers,

[0008] - a third travel - hydraulic motor, which is assigned to the third drive roller segment of the two drive rollers,

[0009] - a fourth travel - hydraulic motor, which is assigned to the fourth drive roller segment of the two drive rollers,

[0010] - a first travel - hydraulic pump,

[0011] - Second travel - hydraulic pump,

[0012] - At least one drive motor for driving the first travel - hydraulic pump and the second travel - hydraulic pump to

[0013] deliver hydraulic fluid to the travel - hydraulic motor, wherein:

[0014] - The first fluid connection of the first travel - hydraulic pump is connected, or can be connected, via a first hydraulic line to the first fluid connection of the first travel - hydraulic motor and the first fluid connection of the second travel - hydraulic motor.

[0015]

[0016]

[0017] - The first fluid connection of the second travel - hydraulic pump is connected, or can be connected, via a second hydraulic line to the first fluid connection of the third travel - hydraulic motor and the first fluid connection of the fourth travel - hydraulic motor.

[0018]

[0019]

[0020] - The second fluid connection of the first travel - hydraulic pump is connected, or can be connected, via a third hydraulic line to the second fluid connection of the second travel - hydraulic motor and the second fluid connection of the third travel - hydraulic motor.

[0021]

[0022]

[0023] - The second fluid connection of the second travel - hydraulic pump is connected, or can be connected, via a fourth hydraulic line to the second fluid connection of the first travel - hydraulic motor and the second fluid connection of the fourth travel - hydraulic motor.

[0024] For a surface processing machine constructed according to the invention, regardless of the direction of fluid flow and thus regardless of the direction of rotation of the travel - hydraulic motor, the travel - hydraulic motors assigned to different drive roller sections are cross - connected with the two travel - hydraulic pumps on the outlet side. This means that on the outlet side, not both of the two travel - hydraulic motors connected to one of the two travel - hydraulic pumps on the inlet side are connected to the travel - hydraulic pump. One of the two travel - hydraulic motors connected to the same travel - hydraulic pump on the inlet side is connected to the other travel - hydraulic pump on the outlet side together with the other travel - hydraulic motor.

[0025]

[0026] ​​​​​​​Therefore, if one of the drive roller sections slips, a larger amount of liquid cannot flow out through the travel - hydraulic motor assigned to this drive roller section. As a result, the travel - hydraulic pump connected to the outflow side of this travel - hydraulic motor only receives the amount of liquid limited by its rotational speed even in the slipping state. And thereby, the amount of liquid flowing out through the travel - hydraulic motor of the slipping drive roller section is basically limited by the amount of liquid output by the travel - hydraulic motor that is connected to the same travel - hydraulic pump on the outflow side together with this travel - hydraulic motor.

[0027] Due to the cross - connection of the travel - hydraulic motor and the travel - hydraulic pump on the outflow side and without the need to set up a flow divider, it is possible to avoid the excessive outflow of liquid through the travel - hydraulic motor assigned to the slipping drive roller section. Thus, a hydraulic drive system design with a significantly simpler structure is achieved. And since a flow divider usually causes energy losses, the energy provided for driving the travel - hydraulic pump can be utilized more effectively. This is especially advantageous for electro - hydraulic drive systems because in such electro - hydraulic drive systems, the travel - hydraulic pump is driven by at least one electric drive motor, and the amount of electrical energy that can be stored in the energy storage device is limited, and thus the operating range or working duration of the surface processing machine is also limited.

[0028] To ensure that in the simple design of the hydraulic drive system, the two travel - hydraulic pumps basically deliver the same amount of liquid so that all travel - hydraulic motors can achieve the same rotational speed, the two travel - hydraulic pumps can be driven by a common drive motor to deliver hydraulic liquid, or / and, the two travel - hydraulic pumps can have the same delivery volume. In addition, all travel - hydraulic motors have the same intake volume per revolution (Schluckvolumen). Here, the delivery volume of the travel - hydraulic pump can be, for example, the amount of liquid output by the travel - hydraulic pump per revolution, and the intake volume per revolution of the travel - hydraulic motor can be the amount of liquid received by the travel - hydraulic motor per revolution.

[0029] To drive the surface processing machine electro - hydraulically, at least one drive motor can be an electric motor.

[0030] Especially in an electro - hydraulic drive system, that is, when one or more drive motors are configured as electric motors, it is advantageous to maintain a hydraulically driven device with a simple structure if each travel - hydraulic pump is a pump with a fixed delivery volume or / and if each travel - hydraulic motor is a motor with a fixed intake volume per revolution. This means that during operation, the travel - hydraulic pump or the travel - hydraulic motor does not need to be adjusted to achieve different rotational speeds of the surface processing machine and thus different travel speeds of the surface processing machine. This can be achieved only by changing the rotational speed of one or more drive motors.

[0031] In order to further improve the slip control, an extended crosslinking of the drive - hydraulic motor can be achieved in the following way:

[0032] - Provide a first valve unit and a second valve unit, which are assigned to the second

[0033] fluid connection of the first drive - hydraulic motor, where the first valve unit is used to selectively establish and interrupt the connection between the second fluid connection of the first drive - hydraulic motor and the third hydraulic line, and the second valve unit is used to selectively establish and interrupt the connection between the second fluid connection of the first drive - hydraulic motor and the fourth hydraulic line

[0034] of the connection,

[0035] and

[0036] - Provide a third valve unit and a fourth valve unit, which are assigned to the second

[0037] fluid connection of the second drive - hydraulic motor, where the third valve unit is used to selectively establish and interrupt the connection between the second fluid connection of the second drive - hydraulic motor and the third hydraulic line, and the fourth valve unit is used to selectively establish and interrupt the connection between the second fluid connection of the second drive - hydraulic motor and the fourth hydraulic line.

[0038] Thereby, it is possible to change the pairing of the drive - hydraulic motors connected to the same drive - hydraulic pump on the outflow side based on which drive - roller section slip occurs.

[0039] In order to be able to change the cross - connection between the drive - hydraulic motor and the drive - hydraulic pump in a defined manner based on which drive - roller section slip occurs, a control device can be provided to control the first valve unit, the second valve unit, the third valve unit, and the fourth valve unit, which is designed for the following purposes:

[0040] - When the first valve unit is operated to establish the connection between the second fluid connection of the first drive - hydraulic motor and the third

[0041] hydraulic line and when the fourth valve unit is operated to establish the connection between the second fluid connection of the second drive - hydraulic motor and the fourth hydraulic line, operate the second valve unit to interrupt the connection between the second fluid connection of the first drive - hydraulic motor and the fourth hydraulic line, and operate the third valve unit to interrupt the connection between the second fluid connection of the second drive - hydraulic motor and the third hydraulic line

[0042] of the connection,

[0043] and

[0044] - When the first valve unit is operated to interrupt the connection between the second fluid connection of the first drive - hydraulic motor and the third

[0045] When connecting the hydraulic pipelines and when the fourth valve unit is operated to interrupt the connection between the second fluid connection of the second travel - hydraulic motor and the fourth hydraulic pipeline, operate the second valve unit to establish the connection between the second fluid connection of the first travel - hydraulic motor and the fourth hydraulic pipeline, and operate the third valve unit to establish the connection between the second fluid connection of the second travel - hydraulic motor and the third hydraulic pipeline.

[0046] In order to be able to compensate for fluid leakage, for example, fluid leakage in the area of the travel - hydraulic motor, a fluid - feeding device (Fluid - Einspeiseanordnung) can be provided for feeding fluid into at least one of the first fluid pipeline, the second fluid pipeline, the third fluid pipeline, and the fourth fluid pipeline.

[0047] Generally speaking, such a fluid - feeding device is designed in such a way that it feeds fluid on the low - pressure side of the hydraulic circuit, that is, feeds fluid into the hydraulic pipeline connecting the outlet side of the travel - hydraulic motor to the travel - hydraulic pump, so as to maintain the hydraulic pressure at a defined level within the scope of these pipelines. In the case of interacting with such a fluid - feeding device, when slipping occurs at the drive roller section, the assigned travel - hydraulic motor operates at a slightly higher speed for a short time and thus also has a correspondingly larger amount of fluid flowing out. In addition, the larger amount of fluid flowing out through such a travel - hydraulic motor can also be compensated by a smaller fluid feed through the fluid - feeding device, even though it is in principle limited by the amount of fluid fed back from another travel - hydraulic motor to the same travel - hydraulic pump. Through this interaction, the travel - hydraulic motor assigned to the drive roller section with a traction loss (Traktionsverlust) is set to a smaller drive torque, which corresponds to the maximum drive torque that can be transmitted without slipping through this drive roller section.

[0048] The first drive roller of the two drive rollers can include a first drive roller section and a second drive roller section, and the second drive roller of the two drive rollers can include a third drive roller section and a fourth drive roller section.

[0049] In order to reduce the probability of the following state occurring, that is, two travel - hydraulic motors that would in principle limit the liquid outflow rate to each other simultaneously reach the slipping state, by distributing the cross - connected travel - hydraulic motors to different drive roller sections in a defined manner, it is proposed that, relative to the longitudinal direction of the machine, the first drive roller section and the third drive roller section are arranged on the first side of the surface processing machine, and the second drive roller section and the fourth drive roller section are arranged on the second side of the surface processing machine. This way of distributing the travel - hydraulic motors to the drive roller sections further enables different rotational speeds to possibly occur in the drive roller sections on the inner and outer sides of the bend during a turning travel, without the situation where the travel - hydraulic motors connected to each other on the outflow side and the liquid amounts respectively output from them are blocked from each other.

[0050] In a design of the surface processing machine designed as a surface compactor, at least one of the two drive rollers can be a surface processing roller, and each drive roller section of at least one drive roller is provided by a roller section. Alternatively or additionally, at least one of the two drive rollers includes at least two wheels, and each drive roller section of at least one drive roller includes at least one wheel. Such drive wheels can be drive wheels purely for driving the surface processing machine, for example, drive wheels positioned on both sides of the rear vehicle, or for example, rubber - wheel pairs that can be rubber - wheel drums.

[0051] In order to be able to take appropriate measures in case of slipping, for example, by switching different defined valve units, a slipping detection device (Schlupferfassungsanordnung) can be set up to detect the slipping state of at least one drive roller section (preferably each drive roller section).

[0052] Here, the slipping detection device assigned to at least one drive roller section (preferably each drive roller section) can include a rotational speed sensor. Description of the Drawings

[0053] The present invention will be described in detail below with reference to the drawings. In the drawings:

[0054] Figure 1 A schematic diagram of a surface processing machine configured as a surface compactor with two surface processing rollers is shown;

[0055] Figure 2 A schematic diagram of another alternative design of a surface processing machine configured as a surface compactor is shown;

[0056] Figure 3 A design of an electro - hydraulic drive system for a surface processing machine is shown;

[0057] Figure 4Shows another alternative design of the electro-hydraulic drive system for a surface processing machine. Detailed implementation

[0058] Figure 1 Shows a schematic view of a surface processing machine, which is generally labeled 10 and is configured, for example, as a surface compactor. The surface processing machine 10 configured as a surface compactor includes two drive rollers 12, 14 arranged in sequence in the machine longitudinal direction R and each configured as a surface processing roller. The drive roller 12 can rotate about a first rotation axis D1, and the drive roller 14 can rotate about a second rotation axis D2. Two travel-hydraulic motors M1, M2 or M3, M4 are assigned to each of the two drive rollers 12, 14. For example, the travel-hydraulic motors M1, M2, M3, M4 assigned to the respective drive rollers 12 or 14 can be provided at the axial ends of the drive rollers 12 or 14 respectively.

[0059] The two drive rollers 12, 14 are configured as divided (geteilt) surface processing rollers, which have corresponding drive roller sections 12a, 12b or 14a, 14b. One of the four travel-hydraulic motors M1, M2, M3, M4 is assigned to each of the drive roller sections 12a, 12b, 14a, 14b, so that the two drive roller sections 12a, 12b can be independently driven by the travel-hydraulic motors M1, M2 assigned to them to rotate about the rotation axis D1, and the two drive roller sections 14a, 14b can be independently driven by the travel-hydraulic motors M3, M4 assigned to them to rotate about the rotation axis D2.

[0060] Figure 2 Shows another alternative design of the surface processing machine 10, which is configured, for example, as a surface processing roller. Figure 2 The surface processing machine 10 (in its longitudinal region) also includes a drive roller 12 configured as a surface processing roller, which has two travel-hydraulic motors M1, M2 assigned to it. In this design, the drive roller 12 also includes two drive roller sections 12a, 12b, which can be independently driven by the respective assigned travel-hydraulic motors M1, M2 to rotate about the rotation axis D1. In another longitudinal end region of the surface processing machine 10, the drive roller 14 includes wheels 16, 18, 20, 22. These wheels can be paired with each other, for example, and each pair of wheels 16, 18 or 20, 22 forms a drive roller section 14a, 14b, which can be driven by the travel-hydraulic motor M3 or M4 assigned to it to rotate about the rotation axis D2.

[0061] It should be noted that other design solutions of such a surface processing machine can also be used for the hydraulic drive system described below. For example, in a surface processing machine configured as a surface compactor, a pair of drive wheels can be provided on the rear vehicle, and the drive wheels form the respective drive roller sections of the drive roller, while the surface processing roller divided into roller sections on the front vehicle can act as the drive roller. The principle of the present invention can be applied to pivotally supported (schemelgelenkten) surface processing machines or surface compactors, as well as to surface processing machines divided into a front vehicle and a rear vehicle.

[0062] Figure 3 A hydraulic drive system 24 is shown, which is an electro-hydraulic drive system in the shown design example and can, for example, be combined with the surface processing machine referred to above with reference Figure 1 and 2 described for use.

[0063] In a hydraulic circuit 26, the hydraulic drive system 24 includes two travel - hydraulic pumps P1, P2 and four travel - hydraulic motors M1, M2, M3, M4. These two travel - hydraulic pumps P1, P2 can be jointly driven by a drive motor E configured as an electric motor.

[0064] A first fluid connection 28 of the first travel - hydraulic pump P1 is connected via a first hydraulic line L1 to a first fluid connection 30 of the first travel - hydraulic motor M1 and a first fluid connection 32 of the second travel - hydraulic motor M2. A first fluid connection 34 of the second travel - hydraulic pump P2 is connected via a second hydraulic line L2 to a first fluid connection 36 of the third travel - hydraulic motor M3 and a first fluid connection 38 of the fourth travel - hydraulic motor M4.

[0065] A second fluid connection 40 of the first travel - hydraulic pump P1 is connected via a third fluid line L3 to a second fluid connection 42 of the second travel - hydraulic motor M2 and a second fluid connection 44 of the third travel - hydraulic motor M3. A second fluid connection 46 of the second travel - hydraulic pump P2 is connected via a fourth fluid line L4 to a second fluid connection 48 of the first travel - hydraulic motor M1 and a second fluid connection 50 of the fourth travel - hydraulic motor M4.

[0066] Depending on the direction in which the surface processing machine 10 is to move, for example when traveling forward, the drive motor E is controlled by a control unit 52 so as to operate the travel - hydraulic pumps P1, P2 in such a conveying direction that the liquid is fed into the first hydraulic line L1 or the second hydraulic line L2 at their respective first fluid connections 28, 34, and thereby feed the liquid (such as hydraulic oil) under high pressure into the travel - hydraulic motors M1, M2, M3, M4 through the respective first fluid connections 30, 32, 36, 38.

[0067] In this state, the travel - hydraulic motors M1, M2, M3, M4 output the liquid under significantly reduced pressure at their respective second liquid connectors 48, 42, 44, 50 into the third hydraulic line L3 or the fourth hydraulic line L4, and the liquid returns to the second liquid connectors 40, 46 of the travel - hydraulic pumps P1, P2 through these lines.

[0068] If the surface working machine 10 moves in the opposite direction (e.g., in the reverse travel direction), the drive motor E is controlled such that the travel - hydraulic pumps P1, P2 driven by the drive motor E output the liquid through their respective second liquid connectors 40, 46 into the third hydraulic line L3 or the fourth hydraulic line L4. Through the third hydraulic line L3, the liquid conveyed by the first travel - hydraulic pump P1 flows to the second liquid connector 42 of the second travel - hydraulic motor M2 and the second liquid connector 44 of the third travel - hydraulic motor M3. Through the fourth hydraulic line L4, the liquid conveyed by the second travel - hydraulic pump P2 flows to the second liquid connector 48 of the first travel - hydraulic motor M1 or the second liquid connector 50 of the fourth travel - hydraulic motor M4. In this operating state, the first travel - hydraulic motor M1 and the second travel - hydraulic motor M2 output the liquid at their first liquid connectors 30, 32 through the first hydraulic line L1 to the first liquid connector 28 of the first travel - hydraulic pump P1, and the third travel - hydraulic motor M3 and the fourth travel - hydraulic motor M4 output the liquid at their first liquid connectors 36, 38 through the second hydraulic line L2 to the first liquid connector 34 of the second travel - hydraulic pump P2.

[0069] The feed device generally designated by 53 compensates for the liquid leakage occurring in the region of the travel - hydraulic motors M1, M2, M3, M4 by feeding the liquid separately to the low - pressure side of the hydraulic circuit 26. For this purpose, the feed device 54 includes, for example, a feed pump S driven by an assigned drive motor, which pumps the liquid from the liquid storage container F and feeds it through four feed valves E1, E2, E3, E4 into the first hydraulic line L1, the second hydraulic line L2, the third hydraulic line L3 or the fourth hydraulic line L4 respectively.

[0070] In Figure 2In the hydraulic drive system 24 shown, independent of the direction of movement of the surface working machine 10 or independent of the direction of rotation of the travel - hydraulic motors M1, M2, M3, M4 assigned to different drive roller sections 12a, 12b, 14a, 14b, both travel - hydraulic motors are connected to the same travel - hydraulic pump P1 or P2 on the high - pressure side (i.e., the inflow side). When outputting liquid through the respective first liquid connectors 28, 34 of the travel - hydraulic pumps P1, P2, the travel - hydraulic motors M1, M2 are connected to the first travel - hydraulic pump 28 on the high - pressure side, and the travel - hydraulic motors M3, M4 are connected to the second travel - hydraulic pump P2 on the high - pressure side.

[0071] However, on the low - pressure side (i.e., the outflow side), the travel - hydraulic motor connected to one of the travel - hydraulic pumps on the high - pressure side is not connected to the same travel - hydraulic pump. Only one of the travel - hydraulic motors connected to the travel - hydraulic pump on the high - pressure side is also connected to the travel - hydraulic pump on the low - pressure side, while the other travel - hydraulic motor is connected to the other travel - hydraulic pump on the low - pressure side. In the shown design example, this means that when outputting liquid through the first liquid connectors 28, 34 of the travel - hydraulic pumps P1, P2, the second travel - hydraulic motor M2 and the third travel - hydraulic motor M3 are connected to the first travel - hydraulic pump P1 through the third hydraulic line M3, and the first travel - hydraulic motor M1 and the fourth travel - hydraulic motor M4 are connected to the second travel - hydraulic pump P2 through the fourth hydraulic line M4.

[0072] When moving in the opposite direction, i.e., when outputting liquid through the respective second liquid connectors 40, 46 of the travel - hydraulic pumps P1, P2, on the high - pressure side, i.e., through the third hydraulic line L3, the second travel - hydraulic motor M2 and the third travel - hydraulic motor M3 are connected to the first travel - hydraulic pump 28, and through the fourth hydraulic line L4, the first travel - hydraulic motor M1 and the fourth travel - hydraulic motor M4 are connected to the second travel - hydraulic pump P2. In this state, on the low - pressure side, the first travel - hydraulic motor M1 and the second travel - hydraulic motor M2 are connected to the first travel - hydraulic pump P1 through the first hydraulic line L1, and the third travel - hydraulic motor M3 and the fourth travel - hydraulic motor M4 are connected to the second travel - hydraulic pump P2 through the second hydraulic line L2.

[0073] Since in such a hydraulic drive system 24 each of the travel - hydraulic pumps P1, P2 can only receive on the low - pressure side as much liquid during the delivery operation as it outputs on the high - pressure side, for the cross - connection of the travel - hydraulic motors M1, M2, M3, M4 and the travel - hydraulic pumps P1, P2, each of the travel - hydraulic pumps P1, P2 basically delivers the same amount of liquid, and each of the travel - hydraulic motors M1, M2, M3, M4 basically receives the same amount of liquid. It is particularly advantageous when designed as an electro - hydraulic drive system that the travel - hydraulic pumps P1, P2 have a constant delivery rate and the travel - hydraulic motors M1, M2, M3, M4 have a constant intake volume per revolution. A change in the delivery rate can be caused only by changing the drive speed of the drive motor E configured as an electric motor. For such a design of the travel - hydraulic pumps P1, P2 and the travel - hydraulic motors M1, M2, M3, M4 (each of which has the same delivery rate or intake volume per revolution), all the travel - hydraulic motors M1, M2, M3, M4 rotate at the same speed, or the drive rollers of the respective assigned drive roller sections 12a, 12b, 14a, 14b rotate at the same speed. This in turn requires that all the drive roller sections 12a, 12b, 14a, 14b have the same diameter. If the drive rollers 12, 14 assigned to different rotation axes D1, D2 are provided with different diameters, then in particular as shown in Figure 1 and 2 when assigning the travel - hydraulic motors M1, M2, M3, M4 to the drive roller sections 12a, 12b, 14a, 14b, travel - hydraulic motors with different intake volumes per revolution can be used for the drive roller sections 12a, 12b on the one hand and for the drive roller sections 14a, 14b on the other hand.

[0074] It is ensured by the cross-connection of the travel - hydraulic motors M1, M2, M3, M4 that none of the drive roller sections 12a, 12b, 14a, 14b will enter a slipping state, in which, due to the increased speed of the assigned travel - hydraulic motor, an excessive amount of fluid will flow out through the travel - hydraulic motor. For example, if slipping occurs due to traction loss on the first drive roller section 12a, this will result in the first travel - hydraulic motor M1 receiving a larger amount of fluid and outputting accordingly due to its correspondingly higher speed. In the state where the first travel - hydraulic motor M1 receives fluid from the first travel - hydraulic pump P1 through the first hydraulic line L1, for example, the first travel - hydraulic motor M1 inputs the received fluid into the fourth hydraulic line L4, and in this state, the fourth travel - hydraulic motor M4 fed by another travel - hydraulic pump P2 outputs an amount of fluid corresponding to normal traction into the fourth hydraulic line L4. The fourth hydraulic line L4 can only receive from the first travel - hydraulic motor M1 in principle the amount of fluid that it would output in a non - slipping state. Therefore, even when the assigned first drive roller section 12a loses traction, the first travel - hydraulic motor M1 cannot rotate faster than the other travel - hydraulic motors M2, M3, M4 in principle and thus will not cause an excessive outflow of fluid from the first hydraulic line L1.

[0075] However, due to the aforementioned fluid leakage, when traction loss occurs at the assigned first drive roller section 12a, in principle, the first travel - hydraulic motor M1 may output a larger amount of fluid in a short time compared to the non - slipping state. The larger amount of fluid fed into the fourth hydraulic line L4 by the first travel - hydraulic motor M1 does not need to be supplemented by the feeding device 53 to maintain the pressure defined at the low - pressure side of the hydraulic circuit 26.

[0076] This short - time increase in speed of the first travel - hydraulic motor M1 caused by slipping results in a spontaneous pressure drop on the high - pressure side (in this case also in the first hydraulic line L1). This pressure drop causes the drive torque generated at the first travel - hydraulic motor to decrease, that is, to a value such that the first drive roller section 12a with less traction can run again without slipping. The decrease in the drive torque on the first travel - hydraulic motor M1 also causes a corresponding decrease in the drive torque of the second travel - hydraulic motor M2, which is under the same pressure. Since the drive power of the drive motor E remains basically constant, a correspondingly higher pressure is generated in the second hydraulic line L2 fed by the second travel - hydraulic pump P2, so that the travel - hydraulic motors M3, M4 fed by the second hydraulic line L2 operate with a correspondingly higher drive torque.

[0077] The aforementioned automatic adjustment of the drive torque or rotational speed of the drive roller section (in the event of a traction loss) is independent of which drive roller section the traction loss occurs on and in which direction the surface working machine 10 moves. Since each travel - hydraulic motor M1, M2, M3, M4 is connected on the outflow side to another travel - hydraulic motor (which is not fed by the same travel - hydraulic pump), the travel - hydraulic motors prevent each other from increasing their rotational speed due to slipping.

[0078] Although the travel - hydraulic motors M1, M2, M3, M4 connected to each other on the outflow side prevent each other, especially for the Figure 1 , 2 and as can be seen in 3, in the case of the assignment of the travel - hydraulic motors M1, M2, M3, M4 to the drive roller sections 12a, 12b, 14a, 14b, it is possible that during a turning travel, compared to a pair of drive roller sections 12a, 14a or 12b, 14b on the outer side of the corresponding bend, each pair of drive roller sections 12a, 14a or 12b, 14b on the inner side of the bend rotates at a lower rotational speed. For example, the lower liquid outflow of the first travel - hydraulic motor M1 caused by the lower rotational speed of the drive roller section 12a is compensated by the correspondingly higher liquid outflow of the fourth travel - hydraulic motor M4, so that the overall liquid outflow is consistent with the sum of the liquid outflows of these two travel - hydraulic motors M1, M4 at the same rotational speed. Correspondingly, this also applies to the travel - hydraulic motors M2, M3 or any pair of travel - hydraulic motors that are connected to each other on the outflow side when moving in the other travel direction.

[0079] Figure 4 An exemplary design of the hydraulic drive system 24 is shown, in which the possibility of a slipping state occurring on one of the drive roller sections 12a, 12b, 14a, 14b can be further reduced. In Figure 4 it can be seen that two valve units V1, V2 or V3, V4 are arranged, for example, to be assigned to the first travel - hydraulic motor M1 and to the second travel - hydraulic motor M2. Through the first valve unit V1, the second liquid connection 48 of the first travel - hydraulic motor M1 can be selectively connected to the third hydraulic line L3 or disconnected from it. Correspondingly, through the second valve unit V2, the second liquid connection 48 of the first travel - hydraulic motor M1 can be selectively connected to the fourth hydraulic line L4 or disconnected from it.

[0080] The valve units V1, V2 controlled by the control unit 52 are basically controlled in such a way that when one of the valve units V1, V2 establishes a connection with the second fluid connection 48 of the first travel - hydraulic motor M1, the other valve unit disconnects from the assigned hydraulic line. Thus, the second fluid connection 48 of the first travel - hydraulic motor M1 is either connected to the third fluid line L3 or to the fourth fluid line L4.

[0081] The third valve unit V3 assigned to the second travel - hydraulic motor M2 selectively establishes or disconnects the connection between the second fluid connection 42 and the third hydraulic line L3. Similarly, the fourth valve unit V4 selectively establishes or disconnects the connection between the second fluid connection 42 of the second travel - hydraulic motor M2 and the fourth fluid line M4. In addition, the two valve units V3, V4 are controlled by the control unit 52 such that when one of the valve units establishes a connection with the assigned hydraulic line, the other valve unit is in its disconnected state.

[0082] Furthermore, when the four valve units V1, V2, V3, V4 are controlled or operated by the control unit 52, a state where the two second output connections 48, 42 of the travel - hydraulic motors M1, M2 are connected to the same hydraulic line L3 or L4 does not occur. As Figure 3 shown, when the second fluid connection 48 of the first travel - hydraulic motor M3 is connected to the fourth hydraulic line L4, the second fluid connection 42 of the second travel - hydraulic motor M2 is connected to the third fluid line L3, and vice versa.

[0083] Therefore, in Figure 4 the switching states of the valve units V1, V2, V3, V4 shown in principle correspond to the unchanged connection states in Figure 3 where the second fluid connection 48 of the first travel - hydraulic motor M1 is connected to the fourth hydraulic line L4, and the second fluid connection 42 of the second travel - hydraulic motor M2 is connected to the third fluid line L3.

[0084] If, in this state, a traction loss occurs on two of the drive roller sections 12a, 14a or 12b, 14b, and the drive roller sections 12a, 14a or 12b, 14b are located on the same side of the soil compactor 10 with respect to the machine longitudinal direction R, that is, on the same side in the machine transverse direction Q, a fluid short - circuit will occur in the hydraulic circuit 26. In this case, all the fluid delivered by the travel - hydraulic pumps P1, P2 flows out through the travel - hydraulic motor assigned to the slipping drive roller section, and no fluid flows out through the travel - hydraulic motor assigned to the non - slipping drive roller section.

[0085] To solve this problem, inFigure 4 In the hydraulic drive system 26 shown, the speed sensors 54, 56, 58, 60 of the slip detection device 62 are arranged to be assigned to the travel - hydraulic motors M1, M2, M3, M4. Information regarding which drive roller sections 12a, 14a, 12b, 14b have traction loss is provided to the control unit 52 by the speed signals output by the speed sensors 54, 56, 58, 60.

[0086] For example, if traction loss accompanied by corresponding slip occurs simultaneously on the drive roller sections 12b, 14b, this will result in all the liquid fed into the second hydraulic line L2 flowing out through the fourth travel - hydraulic motor M4, and all the liquid fed into the first hydraulic line L1 flowing out through the second travel - hydraulic motor M2 in the switching state shown in Figure 3 The four valve units V1, V2, V3, V4 can be switched according to the switching state shown in Figure 3 such that the first travel - hydraulic motor M1 is coupled to the third hydraulic line L3 on the outflow side, while the second travel - hydraulic motor M2 is coupled to the fourth hydraulic line L4 on the outflow side. In this state, the two travel - hydraulic motors M2, M4 (which are assigned to the drive roller sections 12b, 14b with traction loss) are interconnected with each other on the outflow side, so that since the second travel - hydraulic pump P2 can only receive a defined amount of liquid at its second liquid connection 46, the amount of liquid flowing out through these travel - hydraulic motors M2, M4 is basically restricted to the amount of liquid flowing through them in the non - slip state.

[0087] It should be noted that in an alternative design, if the valve units V1, V2, V3, V4 are used in conjunction with the travel - drive motors M3, M4 and the hydraulic lines L3, L4, or if the valve units V1, V2, V3, V4 are used in conjunction with the travel - hydraulic motors M2 and M3, or if the travel - hydraulic motors M1, M4 are used in conjunction, and in each case are assigned to the first hydraulic line L1 and the second hydraulic line L2, the variability brought about by the valve units V1, V2, V3, V4 can also be achieved.

Claims

1. A ground processing machine, comprising two drive rollers (12, 14) arranged one after the other in the longitudinal direction of the machine and rotatable about respective rotation axes (D1, D2), wherein each drive roller (12, 14) comprises two drive roller sections (12a, 12b, 14a, 14b) arranged one after the other in the direction of the assigned rotation axis (D1, D2), and a hydraulic drive system (24) for the drive rollers (12, 14), wherein the hydraulic drive system (14) comprises: a first hydraulic travel motor (M1), which is assigned to a first drive roller section (12a) of the two drive rollers (12, 14), a second travel hydraulic motor (M2), which is assigned to the second drive roller section (12b) of the two drive rollers (12, 14), a third hydraulic travel motor (M3), which is assigned to the third drive roller section (12a) of the two drive rollers (12, 14), a fourth hydraulic travel motor (M4), which is assigned to a fourth drive roller section (12b) of the two drive rollers (12, 14), - First travel hydraulic pump (P1), - Second travel hydraulic pump (P2), - at least one drive motor (E) for driving the first travel hydraulic pump (P1) and the second travel hydraulic pump (P2) to deliver hydraulic fluid to the travel hydraulic motors (M1, M2, M3, M4), in: - a first fluid connection (28) of the first travel hydraulic pump (P1) is connected or can be connected to a first fluid connection (30) of the first travel hydraulic motor (M1) and a first fluid connection (32) of the second travel hydraulic motor (M2) via a first hydraulic line (L1), - the first fluid connection (34) of the second travel hydraulic pump (P2) is connected or can be connected to the first fluid connection (36) of the third travel hydraulic motor (M3) and the first fluid connection (38) of the fourth travel hydraulic motor (M4) via a second hydraulic line (L2), - the second fluid connection (40) of the first travel hydraulic pump (P1) is connected to the second fluid connection (42) of the second travel hydraulic motor (M2) and the second fluid connection (43) of the second travel hydraulic motor (M2) through a third hydraulic line (L3) The third travel hydraulic motor (M3) is connected to the second fluid connection (44), or can be connected thereto, The second hydraulic connection (46) of the second travel hydraulic pump (P2) is connected or can be connected to the second hydraulic connection (48) of the first travel hydraulic motor (M1) and the second hydraulic connection (50) of the fourth travel hydraulic motor (M4) via a fourth hydraulic line (L4).

2. The floor processing machine according to claim 1, It is characterized in that The two travel hydraulic pumps (P1, P2) are driven by a common drive motor (E) to deliver hydraulic fluid, or / and the two travel hydraulic pumps (P1, P2) have the same delivery volume, or / and all travel hydraulic motors (M1, M2, M3, M4) have the same fluid intake per revolution.

3. The floor processing machine according to claim 1 or 2, It is characterized in that At least one of the drive motors (E) is an electric motor.

4. The floor processing machine according to any one of claims 1 to 3, It is characterized in that Each travel hydraulic pump (P1, P2) is a pump with a fixed delivery volume, and / or each travel hydraulic motor (M1, M2, M3, M4) is a motor with a fixed fluid intake per revolution.

5. The floor processing machine according to any one of claims 1 to 4, It is characterized in that - providing a first valve unit (V1) and a second valve unit (V2), wherein the first valve unit (V1) and the second valve unit (V2) are assigned to the second liquid connection (48) of the first travel hydraulic motor (M1), the first valve unit (V1) being used for selectively establishing and interrupting the connection between the second liquid connection (48) of the first travel hydraulic motor (M1) and the third hydraulic line (L3), and the second valve unit (V2) being used for selectively establishing and interrupting the connection between the second liquid connection (48) of the first travel hydraulic motor (M1) and the fourth hydraulic line (L4), as well as - A third valve unit (V3) and a fourth valve unit (V4) are provided, wherein the third valve unit (V3) and the fourth valve unit (V4) are assigned to the second liquid connector (42) of the second travel hydraulic motor (M2), the third valve unit (V3) is used for selectively establishing and interrupting the connection between the second liquid connector (42) of the second travel hydraulic motor (M2) and the third hydraulic pipeline (L3), and the fourth valve unit (V4) is used for selectively establishing and interrupting the connection between the second liquid connector (42) of the second travel hydraulic motor (M2) and the fourth hydraulic pipeline (L4).

6. The floor processing machine according to claim 5, It is characterized in that A control device (52) is provided to control the first valve unit (V1), the second valve unit (V2), the third valve unit (V3) and the fourth valve unit (V4), wherein the control device (52) is designed for the following purposes: - when the first valve unit (V1) is operated to establish a connection between the second liquid connector (48) of the first travel hydraulic motor (M1) and the third hydraulic line (L3) and when the fourth valve unit (V4) is operated to establish a connection between the second liquid connector (42) of the second travel hydraulic motor (M2) and the fourth hydraulic line (L4), the second valve unit (V2) is operated to interrupt the connection between the second liquid connector (48) of the first travel hydraulic motor (M1) and the fourth hydraulic line (L4), and the third valve unit (V3) is operated to interrupt the second liquid connector (42) of the second travel hydraulic motor (M2) connection with the third hydraulic line (L3), as well as - when the first valve unit (V1) is operated to interrupt the connection between the second liquid joint (48) of the first travel hydraulic motor (M1) and the third hydraulic line (L3) and when the fourth valve unit (V4) is operated to interrupt the connection between the second liquid joint (42) of the second travel hydraulic motor (M2) and the fourth hydraulic line (L4), the second valve unit (V2) is operated to establish the connection between the second liquid joint (48) of the first travel hydraulic motor (M1) and the fourth hydraulic line (L4), and the third valve unit (V3) is operated to establish the second liquid joint (42) of the second travel hydraulic motor (M2) Connection with the third hydraulic pipeline (23).

7. The floor processing machine according to any one of claims 1 to 6, It is characterized in that A liquid feeding device (53) is provided to feed liquid to at least one of the first liquid pipeline (L1), the second liquid pipeline (L2), the third liquid pipeline (L3) and the fourth liquid pipeline (L4).

8. The floor processing machine according to any one of claims 1 to 7, It is characterized in that The first drive roller (12) of the two drive rollers (12, 14) includes the first drive roller section (12a) and the second drive roller section (12b), and the second drive roller (14) of the two drive rollers (12, 14) includes the third drive roller section (14a) and the fourth drive roller section (14b).

9. The floor processing machine according to claim 8, It is characterized in that Relative to the longitudinal direction (R) of the machine, the first drive roller segment (12a) and the third drive roller segment (14a) are arranged on a first side of the ground processing machine (10), and the second drive roller segment (12b) and the fourth drive roller segment (14b) are arranged on a second side of the ground processing machine (10).

10. The floor processing machine according to any one of claims 1 to 9, It is characterized in that At least one of the two drive rollers (12, 14) is a ground processing roller, wherein each drive roller segment (12a, 12b, 14a, 14b) of at least one drive roller (12, 14) is provided by a roller segment, or / and at least one of the two drive rollers (12, 14) comprises at least two wheels (16, 18, 20, 22), wherein each drive roller segment (14a, 14b) of at least one drive roller (14) comprises at least one wheel (16, 18, 20, 22).

11. The floor processing machine according to any one of claims 1 to 10, It is characterized in that A slip detection device (62) is provided to detect the slip state of at least one drive roller segment (12a, 12b, 14a, 14b), preferably to detect the slip state of each drive roller segment (12a, 12b, 14a, 14b).

12. The floor processing machine according to claim 11, It is characterized in that The slip detection device (62) comprises a rotational speed sensor (56, 58, 60, 62) which is assigned to at least one drive roller segment (12a, 12b, 14a, 14b), preferably to each drive roller segment (12a, 12b, 14a, 14b).

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