EP4158155A1

EP4158155A1 - A drum cutter arrangement

Info

Publication number: EP4158155A1
Application number: EP20729991.8A
Authority: EP
Inventors: Torsten Ahr; Roger DÄHNE; Janis SEIFERT
Original assignee: Construction Tools GmbH
Current assignee: Construction Tools GmbH
Priority date: 2020-05-28
Filing date: 2020-05-28
Publication date: 2023-04-05
Also published as: WO2021239225A1

Abstract

24 Abstract The invention relates to a drum cutter arrangement (10) for a carrier vehicle (1), the drum cutter arrangement (10) comprising: a main element (20) with a longitudinal extension (L); a first and a second rotatable cutting drum (31, 32) 5 connected to, and arranged on opposite sides of, the main element (20); and a drive system (40) arranged to drive the first and second cutting drum (31, 32), wherein the first cutting drum (31) is rotatable around a first axis (33) and the second cutting drum (32) is rotatable around a second axis (34), wherein the cutting drums (31, 32) are arranged with the first axis (33) and the second axis 10 (34) inclined in relation to a first plane (P) perpendicular to the longitudinal extension (L) of the main element (20), with an angle (α) between the first axis (33) and the second axis (34). 15 (Fig. 1)

Description

A drum cutter arrangement

TECHNICAL FIELD

The present invention relates to a drum cutter arrangement for a carrier vehicle. The invention also relates to a vehicle comprising such a drum cutter arrangement.

BACKGROUND

Transverse drum cutter arrangements are commonly known and are typically used for rock cutting applications, such as trenching, tunnelling, mining or similar. The drum cutter arrangement is thus typically mounted on a carrier vehicle, such as an excavator or another construction vehicle. Known drum cutter arrangements may be direct driven or gear driven and are typically hydraulic attachments connected to the hydraulic system of the carrier vehicle. A conventional transverse drum cutter arrangement comprises a housing and two cutting drums arranged on opposite sides of the housing. Typically, a spur gear drive is used and is arranged inside the housing. The housing has a certain width and will thereby cause a distance between the cutting drums. The width of the housing between the two cutting drums will thereby cause a ridge of material when the drum cutter arrangement is operating. Thus, the distance between the cutting drums will cause a ridge of material, which is not cut. In order to remove the ridge, the drum cutter arrangement will have to be moved laterally, and such lateral movement may induce additional forces on the carrier vehicle. It is thus desired to minimize the size of, or completely avoid forming, the ridge during operation of the drum cutter arrangement.

One way of solving the problem with the ridge is disclosed in document WO201 2/129593A1 . This document teaches a double-headed rock cutter where the cutting heads are connected to a vertical input shaft with a user determined radial angle about the axis of the input shaft. Document WO2012/045327A1 discloses a cutter head where the transmission element is provided with a plurality of cutter tools, so that the cutter head can dig also in the region in correspondence to the transmission element. SUMMARY

Despite known solutions in the field, it would be desirable to develop a new and advantageous drum cutter arrangement, which overcomes or alleviates at least some of the drawbacks of the prior art.

An object of the present invention is thus to achieve an advantageous drum cutter arrangement, which reduces or eliminates the undesired ridge of material between the cutting drums during operation. Another object of the present invention is to achieve an advantageous drum cutter arrangement, which is robust, reliable and service-friendly, easy to manufacture and easy to assemble.

The herein mentioned objects are achieved by a drum cutter arrangement and a carrier vehicle comprising such a drum cutter arrangement according to the independent claims.

Hence, according to an aspect of the present invention, a drum cutter arrangement for a carrier vehicle is provided, the drum cutter arrangement comprising: a main element with a longitudinal extension; a first and a second rotatable cutting drum connected to, and arranged on opposite sides of, the main element; and a drive system arranged to drive the first and second cutting drum, wherein the first cutting drum is rotatable around a first axis and the second cutting drum is rotatable around a second axis, wherein the cutting drums are arranged with the first axis and the second axis inclined in relation to a first plane perpendicular to the longitudinal extension of the main element, with an angle between the first axis and the second axis. According to another aspect of the invention, a carrier vehicle comprising a drum cutter arrangement as disclosed herein is provided.

The drum cutter arrangement according to the invention may be based on conventional transverse drum cutter concepts and does not require a lot of extra parts. No additional wear parts are required to be replaced and no additional service tasks need to be performed. Thus, maintenance is facilitated. Furthermore, by arranging the cutting drums with the rotational axis inclined in relation to a plane perpendicular to the longitudinal extension of the main element, the cutting drums will be arranged closer to each other at the operational end of the cutting drums. Thus, the end of the cutting drums, which is in contact with the material to be cut, will be arranged closer to each other. The distance between the cutting drums at the operational end will this way be reduced or even eliminated. Thus, by means of the drum cutter arrangement as disclosed herein, the cutting operation is more efficient and exact, no ridge of uncut material is formed and as an effect, there will be less and material to extract and backfill. This will save both time and money. Also, since no ridge of material will remain and the arrangement therefore no longer has to be moved laterally, the machine-induced vibrations will be reduced. Another advantage is that the cutting operation will be more efficient and the fuel consumption of the carrier vehicle will thereby be reduced.

Further objects, advantages and novel features of the present invention will become apparent to one skilled in the art from the following details, and also by putting the invention into practice. Whereas the invention is described below, it should be noted that it is not restricted to the specific details described. Specialists having access to the teachings herein will recognise further applications, modifications and incorporations within other fields, which are within the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

For fuller understanding of the present invention and further objects and advantages of it, the detailed description set out below should be read together with the accompanying drawings, in which the same reference notations denote similar items in the various drawings, and in which:

Figure 1 schematically illustrates a drum cutter arrangement according to an example; Figure 2 schematically illustrates a drum cutter arrangement according to an example;

Figure 3 schematically illustrates a drum cutter arrangement according to an example;

Figure 4a-c schematically illustrate a drum cutter arrangement according to examples;

Figure 5 schematically illustrates a drum cutter arrangement according to an example; Figures 6a-c schematically illustrate details of drum cutter arrangements according to examples; and Figure 7 schematically illustrates a vehicle according to an example.

DETAILED DESCRIPTION

To improve existing drum cutter arrangements and avoid getting a ridge of material between the cutting drums during operation, a drum cutter arrangement and a vehicle according to the present disclosure has been developed. The present drum cutter arrangement is applicable on all sorts of applications, such as trenching, pipeline construction, concrete demolition, construction pits and foundation excavation, quarrying, mineral excavation, tunnelling and mining, road works, foundation piling and pile head cutting, underwater works, steel industry/metallurgical industries, tree stump cutting and soil mixing and soil treatment. The present drum cutter arrangement is thus applicable on all sorts of carrier vehicles. Hence, according to an aspect of the present disclosure, a drum cutter arrangement for a carrier vehicle is provided. The drum cutter arrangement comprises: a main element with a longitudinal extension; a first and a second rotatable cutting drum connected to, and arranged on opposite sides of, the main element; and a drive system arranged to drive the first and second cutting drum, wherein the first cutting drum is rotatable around a first axis and the second cutting drum is rotatable around a second axis, wherein the cutting drums are arranged with the first axis and the second axis inclined in relation to a first plane perpendicular to the longitudinal extension of the main element, with an angle between the first axis and the second axis. The first axis and the second axis may be referred to as the rotational axis of the respective cutting drum.

The drum cutter arrangement as disclosed herein is a transverse drum cutter arrangement. Thus, the cutting drums are arranged essentially transverse to the operational direction or moving direction of the carrier vehicle. The drum cutter arrangement may also be referred to as a drum cutter attachment.

The longitudinal extension of the main element may be referred to as the main extension of the main element. The main element may be essentially vertically arranged when the cutting drums are operating on a horizontal surface. When the main element is vertically arranged, the longitudinal extension of the main element is vertical and the first plane perpendicular to the longitudinal extension is thereby a horizontal plane. In this case, the drum cutters are arranged with the first axis and the second axis inclined in relation to a horizontal plane. The main element may be referred to as a housing and may enclose at least a part of the drive system. The drive system is arranged to provide torque to, and thereby rotate, the first axis and the second axis and thereby drive the cutting drums. The first cutting drum and the second cutting drum both comprises a plurality of cutter picks. The picks may be evenly arranged around the circumference of the cutting drums or they may be arranged with a certain pattern. The picks may be exchangeable. The first cutting drum and the second cutting drum may be synchronous. Thus, the drive system may be configured to drive the first and second cutting drum synchronously.

The first and second cutting drum each comprises a front end, a rear end, a lower/operational end and an upper end. When the drum cutter arrangement is arranged with the main element essentially vertically and is cutting a material on an essentially horizontal surface, the front end faces in the moving direction of the drum cutter arrangement, the rear end faces away from the moving direction, the lower end/operational end is facing downwards and is in contact with the material to be cut, and the upper end faces upwards, away from the material to be cut. The operational end of the cutting drums will always be the end in contact with the material and the upper end is opposite to the operational end. The first and second cutting drum each comprises a proximal end and a distal end, wherein the proximal end is closest to the main element and the distal end is furthest away from the main element.

The cutting drums may be symmetrically arranged on opposite sides of the main element. The cutting drums may be arranged, such that they are aligned at the front of the drum cutter arrangement and thus such that the front end of the cutting drums are aligned. The cutting drums may be arranged, such that they form an essentially straight front line. The front line may be defined as a line connecting the most forward points of the cutting drums. Forward may be defined as the moving direction of the carrier vehicle. The cutting drums of conventional drum cutter arrangements are typically arranged, such that the rotational axis are aligned with each other and in parallel with the horizontal plane when the main element is vertically arranged. The rotational axis of the cutting drums are thus not inclined in relation to the first plane perpendicular to the longitudinal extension of the main element and the angle between the rotational axis is zero or 180 degrees. Thus, the first and the second cutting drum according to the present disclosure being arranged with the first axis and the second axis inclined in relation to the first plane means that the cutting drums are arranged with an angle different from zero or 180 degrees between the first axis and the second axis. The cutting drums may be arranged with the first axis and the second axis inclined in direction towards the material to be cut by means of the cutting drums. The cutting drums may be arranged with the first axis and the second axis inclined in relation to the first plane, such that the distance between the operational ends of the cutting drums is smaller than the distance between the upper ends of the cutting drums. The cutting drums being arranged with the first axis and the second axis inclined in relation to a first plane perpendicular to the longitudinal extension of the main element also means that the cutting drums are arranged with the first axis and the second axis inclined with an inclination angle in relation to the first plane.

The angle between the first axis and the second axis, and thus the inclination angle between the respective axis and the first plane, may vary depending on the application of the drum cutter arrangement and on the shape of the cutting drums. The inclination angle between the axis and the first plane may be chosen to enable a smallest possible width of the remaining ridge of material, and thus to enable a smallest possible distance between the operational ends of the cutting drums. The inclination angle may be chosen to achieve a distance of 20- 50 millimetres between the operational ends of the cutting drums. The inclination angle may also be chosen to enable a smallest possible cutting width of the drum cutter arrangement. The cutting width may be defined as the distance between the distal ends of the cutting drums. Furthermore, the inclination angle may be chosen to avoid having an extreme shape of the cutting drums and at the same time keep the distance between the operational ends of the cutting drums as small as possible. Also, the inclination angle may be chosen to avoid collision between the upper ends of the cutting drums and the main element. According to an example, the angle between the first axis and the second axis is within the range of 120-170 degrees, preferably within the range of 140-160 degrees. Thus, the first and second cutting drum may be arranged with an inclination angle within the range of 5-30 degrees, preferably 10-20 degrees, in relation to the first plane. In some examples, the arrangement of the cutting drums on opposite sides of the main element may be out of symmetry. Thus, the first cutting drum may be arranged with a first inclination angle between the first axis and the first plane, while the second cutting drum may be arranged with a second inclination angle, between the second axis and the first plane; the second inclination angle being different from the first inclination angle. In some examples, the first inclination angle and the second inclination angle are in the range of 5-20 degrees and with a mutual difference of 1-5 degrees.

In one example, the drive system is connectable to a power system of the carrier vehicle. For example, the drive system may be connectable to a hydraulic system of the carrier vehicle or the drive system may be connectable to an energy storage device of the carrier vehicle. The drive system may thus be configured to receive power from the carrier vehicle. According to an example, the drive system comprises a motor and a first gear device connected to the motor to transmit torque to the first and second cutting drum. The motor may be a hydraulic motor and may be configured to receive power from a hydraulic system of the carrier vehicle. Alternatively, the motor is an electric motor and the electric motor may be configured to receive power from an energy storage device of the carrier vehicle. The first gear device may be one or more spur gears connected to each other. The first gear device may be any type of gear connected to the motor and directly or indirectly to the first and second cutting drum to transfer torque to the first and second cutting drum. The first gear device may function as a damping element between the cutting drums and the motor. According to an example, the drive system further comprises two bevel gear sets symmetrically arranged on opposite sides of the first gear device, wherein each bevel gear set is connected to the first gear device and to the first and second cutting drum respectively. Thus, one set of bevel gears is connected to the first gear device and to the first cutting drum, and one set of bevel gears is connected to the first gear device and the second cutting drum. Each set of bevel gears may comprise a first bevel gear and a second bevel gear. The first bevel gear may engage with/be connected to the first gear device and the second bevel gear may be connected to the first axis/second axis of the cutting drums. By means of using bevel gear sets, the first axis and the second axis can be inclined in relation to the first plane. This way, the distance between the operational ends of the cutting drums can be reduced. Also, bevel gears are less complicated and do not require highly specialized tools, which facilitates manufacturing. With a drive system comprising a first gear device, such as a spur gear, and two bevel gear sets symmetrically arranged on opposite sides of the first gear device, the first and second cutting drums will be mechanically synchronously driven. In this example, the first gear device may comprise a first spur gear and a second spur gear, wherein the first spur gear is connected to the motor and to the second spur gear, and wherein the second spur gear is connected to the first spur gear and the bevel gear sets. The first spur gear and the second spur gear may be axially connected.

In another example, the drive system further comprises a crown gear device connected to the first gear device and to the first and second cutting drum. The crown gear device may comprise a first crown gear connected to the first gear device. The crown gear device may further comprise a second crown gear and a third crown gear arranged on opposite sides of the first crown gear. The second crown gear may engage with/be connected to the first crown gear and the first cutting drum, whereas the third crown gear may engage with/be connected to the first crown gear and the second cutting drum. The first crown gear may comprise crown teeth on an outer surface. The first crown gear may also comprise end sections comprising spur teeth. This way, the first crown gear may engage with the first gear device when the first gear device comprises a spur gear.

The drive system may comprise a cardan shaft connected to the first and second cutting drum. The cardan shaft may comprise two joints, one connected to the first cutting drum and the other connected to the second cutting drum.

According to an example, the drive system comprises at least one motor arranged inside any one of the first and the second cutting drum to drive the cutting drums. Thus, the drive system may be a direct drive system. The drive system may comprise two motors arranged inside the cutting drums to drive the first and second cutting drum respectively. The drive system may comprise one motor arranged inside the first cutting drum, and a second motor arranged inside the second cutting drum. The motors may be electrical motors. The first and second cutting drum may in this example be synchronized mechanically or hydraulically. Hydraulic synchronization may be achieved by means of valves or pumps of the drive system. Mechanical synchronization may be achieved by means of a cardan shaft. Thus, the drive system may comprise a cardan shaft connected to the respective motor. This way, the cutting drums will be rotated synchronously. The cardan shaft may comprise two joints, each joint connected to one of the motors. The drive system may alternatively comprise only one motor arranged in the first or the second cutting drum. The single motor is in this example configured to drive both cutting drums. The drive system may in this example further comprise a cardan shaft connected to the motor and to the other cutting drum. The cardan shaft may be connected to the other cutting drum via a bearing device. The cardan shaft may comprise two joints, one joint connected to the motor and one joint connected to the other cutting drum/the bearing device.

The drive system may comprise a motor, two sets of bevel gears and a planetary gear, arranged to transmit torque to the first and second cutting drum. Thus, the drive system may comprise a first set of bevel gears and a planetary gear arranged to transmit torque to the first or second cutting drum, and a second set of bevel gears arranged to transmit torque to the other of the first and second cutting drum. The motor may be vertically mounted to transfer torque to an input shaft connected to the first set of bevel gears. The first set of bevel gears may comprise a first bevel gear connected to the motor (input shaft) and a second bevel gear connected to the first bevel gear and the planetary gear. The planetary gear may comprise a sun gear, planetary gears, a planet carrier and a ring gear according to conventional planetary gears. The second bevel gear may be directly connected to the sun gear. The sun gear may be arranged to drive the planet carrier via the planetary gears. The planet carrier may be connected to the first/second cutting drum and to the second set of bevel gears. The second set of bevel gears may comprise a third bevel gear and a fourth bevel gear. The planet carrier may be connected to the third bevel gear. The third bevel gear may be connected to the fourth bevel gear, wherein the fourth bevel gear is connected to the other of the first/second cutting drum.

The first cutting drum and the second cutting drum may be tapered with a decreasing diameter in direction away from the main element. Thus, the first and the second cutting drum may be tapered from the proximal end towards the distal end. The cutting drums may thus have a frustoconical shape. The cutting drums may be arranged, such that they form an essentially straight operating line facing the material to cut. With tapered cutting drums, the cutting drums can be arranged with inclined rotational axis in relation to the first plane and still achieve an essentially straight operational line. The operational line is thus formed by the operational end of the cutting drums. When the cutting drums are tapered and are arranged with inclined rotational axis, the operational end of the first cutting drum and the operational end of the second cutting drum may be aligned with each other, and they may be essentially in parallel with the first plane. This way, an even and efficient cutting operation can be achieved. The first and second cutting drums may be tapered with an angle within the range of 5-30 degrees, preferably 10-20 degrees. The larger the tapering angle, the more must the cutting drums be inclined in order to achieve an essentially straight operational line. However, inclining the cutting drums too much may make the cutting drums collide with each other and/or the main element. The inclination angle and thus the angle between the cutting drums may thereby depend on the shape of the cutting drums and the configuration and shape of the drive system. The first cutting drum and the second cutting drum may have a cylindrical shape, a concave shape, a convex shape or a combination of concave and convex. In one example, the cutting drums are tapered with a smaller diameter at the distal end than at the proximal end and have a convex circumferential wall. In another example, the cutting drums may be tapered with an increasing diameter in direction away from the main element. For example, the cutting drums may have a concave circumferential wall or an essentially S-shaped circumferential wall with a concave section and a convex section. The shape of the cutting drums may depend on the application in which the drum cutter arrangement is to be used.

According to another aspect of the present disclosure, a vehicle is provided. The vehicle comprises a drum cutter arrangement as disclosed herein. The vehicle may thus be referred to as a carrier vehicle. The vehicle may be an excavator.

The present disclosure will now be further illustrated with reference to the appended figures.

Figure 1 schematically illustrates a front view of a drum cutter arrangement 10 for a carrier vehicle according to an example. The carrier vehicle may be configured as disclosed in Figure 7. The drum cutter arrangement 10 comprises a main element 20 with a longitudinal extension L; a first and a second rotatable cutting drum 31 , 32 connected to, and arranged on opposite sides of, the main element 20; and a drive system 40 arranged to drive the first and second cutting drum 31 , 32, wherein the first cutting drum 31 is rotatable around a first axis 33 and the second cutting drum 32 is rotatable around a second axis 34, wherein the cutting drums 31 , 32 are arranged with the first axis 33 and the second axis 34 inclined in relation to a first plane P perpendicular to the longitudinal extension L of the main element 20, with an angle a between the first axis 33 and the second axis 34. The main element 20 may be referred to as a housing and may enclose at least a part of the drive system 40. The drive system 40 is arranged to provide torque to, and thereby rotate, the first axis 33 and the second axis 34 and thereby drive the cutting drums 31 , 32. The first cutting drum 31 and the second cutting drum 32 may be synchronously driven. Thus, the drive system 40 may be configured to drive the first and second cutting drum 31 , 32 synchronously. The drive system 40 may be connectable to a power system of the carrier vehicle. For example, the drive system 40 may be connectable to a hydraulic system of the carrier vehicle or the drive system 40 may be connectable to an energy storage device of the carrier vehicle. The drive system 40 may thus be configured to receive power from the carrier vehicle. The first cutting drum 31 and the second cutting drum 32 both comprises a plurality of cutter picks 35. In the figure, for clarity, the picks 35 are only showed on the first cutting drum 32. The picks 35 may be arranged to achieve as large operating surface as possible depending on the application. In this figure, the main element 20 is vertically arranged and the first plane P perpendicular to the longitudinal extension L is thereby a horizontal plane. The first 31 and second cutting drum 32 each comprises a front end 61 , a rear end 62, a lower/operational end 63 and an upper end 64. In this figure, the front end 61 is pointing out from the figure, and the rear end 62 is on the opposite side of the front end 61 , and is thereby not seen in the figure. The operational end 63 of the cutting drums 31 , 32 is the end in contact with the material to be cut and the upper end 64 is opposite to the operational end 63. The first and second cutting drum 31, 32 each comprises a proximal end 65 and a distal end 66, wherein the proximal end 65 is closest to the main element 20 and the distal end 66 is furthest away from the main element 20. The cutting drums 31 , 32 may be symmetrically arranged on opposite sides of the main element 20. The cutting drums 31 , 32 may be arranged, such that they are aligned at the front of the drum cutter arrangement 10 and thus such that the front end 61 of the cutting drums 31 , 32 are aligned. The cutting drums 31 , 32 may be arranged with the first axis 33 and the second axis 34 directed towards the material to be cut by means of the cutting drums 31 , 32. The cutting drums 31 , 32 may be arranged with the first axis 33 and the second axis 34 inclined in relation to the first plane P, such that the distance between operational ends 63 of the cutting drums 31 , 32 is smaller than the distance between the upper ends 64 of the cutting drums 31 , 32.

The angle a between the first axis 33 and the second axis 34 may vary depending on the application of the drum cutter arrangement 10 and on the shape of the cutting drums 31 , 32. The angle a between the first axis 33 and the second axis 34 may be within the range of 120-170 degrees, preferably within the range of 140-160 degrees. The inclination angle b/ b’ between the first axis 33/second axis 34 and the first plane P may thus be within the range of 5-30 degrees, preferably 10-20 degrees. In some examples, the arrangement of the cutting drums on opposite sides of the main element may be out of symmetry. Thus, the first cutting drum 31 may be arranged with a first inclination angle b between the first axis 33 and the first plane P, while the second cutting drum 32 may be arranged with a second inclination angle b’, between the second axis 34 and the first plane P; the second inclination angle being different from the first inclination angle. In some examples, the first inclination angle b and the second inclination angle b’ are in the range of 5-20 degrees and with a mutual difference of 1-5 degrees.

In this figure, the first cutting drum 31 and the second cutting 32 are tapered with a decreasing diameter in direction away from the main element 20. Thus, the first and the second cutting drum 31 , 32 are tapered from the proximal end 65 towards the distal end 66. The cutting drums 31, 32 may thus have a frustoconical shape. The cutting drums 31 , 32 may be arranged, such that they form an essentially straight operating line facing the material to cut. When the cutting drums 31 , 32 are tapered and are arranged with inclined rotational axis 33, 34, the operational end 63 of the first cutting drum 31 and the operational end 63 of the second cutting drum 32 may be aligned with each other, and they may be essentially in parallel with the first plane P. This way, an even and efficient cutting operation can be achieved. The first and second cutting drums 31 , 32 may be tapered with an angle g within the range of 5-30 degrees. The first and second cutting drums 31, 32 may preferably be tapered with an angle Y within the range of 10-20 degrees. The tapered angle g may be similar to the inclination angle b. However, the first and the second cutting drum 31 , 32 may have any shape and may not be tapered. Further examples of different shapes of the first and second cutting drums 31 , 32 are shown in Figure 6a-c. Figure 2 schematically illustrates a drum cutter arrangement 10 for a carrier vehicle according to an example. The drum cutter arrangement 10 may be configured as disclosed in Figure 1. In this example, the drive system 40 comprises a motor 41 and a first gear device 42 connected to the motor to transmit torque to the first and second cutting drum 31 , 32. The motor 41 may be a hydraulic motor or an electric motor. The first gear device 42 may be one or more spur gears connected to each other. The first gear device 42 may be any type of gear connected to the motor 41 and directly or indirectly connected to the first and second cutting drum 31 , 32 to transfer torque to the first and second cutting drum 31, 32. In this example, the first gear device 42 comprises a first spur gear 42’ and a second spur gear 42” connected to each other. The first spur gear 42’ is connected to the motor 41 and to the second spur gear 42”, and wherein the second spur gear 42” is connected to the first spur gear 42’ and the bevel gear sets 70. The drive system 40 further comprises two bevel gear sets 70 symmetrically arranged on opposite sides of the first gear device 42, wherein each bevel gear set 70 is connected to the first gear device 42 and to the first and second cutting drum 31, 32 respectively. Each bevel gear set 70 may comprise a first bevel gear 71 and a second bevel gear 72. The first bevel gear 71 may engage with/be connected to the first gear device 42 and the second bevel gear 72 may be connected to the first axis 33/second axis 34 of the cutting drums 31 , 32. By means of using bevel gear sets 70, the first axis 33 and the second axis 34 can be inclined in relation to the first plane P.

Figure 3 schematically illustrates a drum cutter arrangement 10 for a carrier vehicle according to an example. The drum cutter arrangement 10 may be configured as disclosed in Figure 1. In this example, the drive system 40 comprises a motor 41 and a first gear device 42 connected to the motor to transmit torque to the first and second cutting drum 31 , 32. The motor 41 may be a hydraulic motor or an electric motor. The first gear device 42 may be one or more spur gears connected to each other. The first gear device 42 may be any type of gear connected to the motor 41 and directly or indirectly connected to the first and second cutting drum 31 , 32 to transfer torque to the first and second cutting drum 31 , 32. In this example, the first gear device 42 comprises a first spur gear 42’ connected to the motor 41. The drive system 40 further comprises a crown gear device 80 connected to the first gear device 42 and to the first and second cutting drum 31 , 32. The crown gear device 80 may comprise a first crown gear 82 connected to the first gear device 42. The crown gear device 80 may further comprise a second crown gear 84 and a third crown gear 86 arranged on opposite sides of the first crown gear 82. The second crown gear 84 may engage with/be connected to the first crown gear 42 and the first cutting drum 31 , whereas the third crown gear 86 may engage with/be connected to the first crown gear 42 and the second cutting drum 32. The first crown gear 82 may comprise crown teeth on an outer surface. The first crown gear 82 may also comprise an end section 88 comprising spur teeth.

Figures 4a-c schematically illustrate drum cutter arrangements 10 for carrier vehicles according to examples. The drum cutter arrangement 10 may be configured as disclosed in Figure 1. In these examples, the drive system 40 comprises at least one motor 44 arranged inside the first drum cutter 31 or the second drum cutter 32 to drive the drum cutters 31 ,32. Thus, Figures 4a-4c shows drum cutter arrangements 10 where the drive system 40 is a direct drive system. Figure 4a and 4b both shows a drum cutter arrangement 10 where the drive system 40 comprises two motors 44 arranged inside the cutting drums 31, 32 to drive the first and second cutting drum 31, 32 respectively. The drive system 40 thus comprises one motor 44 arranged inside the first cutting drum 31 , and another motor 44 arranged inside the second cutting drum 32. The motors 44 may be electrical motors.

Figure 4a shows a drum cutter arrangement 10 where the first and second cutting drum 31, 32 are hydraulically synchronized. In this example, the drive system 40 further comprises hydraulic components 46, such as hydraulic hoses, valves and/or pumps. The hydraulic components 46 may be arranged in the main element 20.

Figure 4b shows a drum cutter arrangement 10 where the first and second cutting drum 31, 32 are mechanically synchronized. In this example, the drive system 40 further comprises a cardan shaft 90 connected to the motors 44. The cardan shaft 90 may comprise two joints 92, each connected to a motor 44. This way, the cutting drums 31 , 32 will be rotated synchronously.

Figure 4c shows a drum cutter arrangement 10 where the drive system 40 comprises one motor 44 arranged in the first or second cutting drum 31 , 32 to drive both cutting drums 31 , 32. In this figure, the motor 44 is arranged inside the first cutting drum 31. The drive system 40 further comprises a cardan shaft 90 connected to the motor 44 and to the second cutting drum 32. The cardan shaft 90 may comprise two joints 92. One joint 92 may be connected to the motor 44 in the first cutting drum 31 and the other joint 92 may be connected to the second cutting drum 32. The drive system 40 may also comprise a bearing device 48 mounted in the second cutting drum 32. The cardan shaft 90 may thus be connected to the second cutting drum 32 via the bearing device 48.

Figure 5 schematically illustrates a drum cutter arrangement 10 according to an example. The drum cutter arrangement 10 may be configured as disclosed in Figure 1. In this example, the drive system 40 comprises a motor 110, two sets 120 of bevel gears 122 and a planetary gear 124 arranged to transmit torque to the first and second cutting drum 31, 32. Thus, the drive system 40 may comprise a first set 120 of bevel gears 122 and a planetary gear 124 arranged to transmit torque to the first or second cutting drum 31, 32 and a second set 120 of bevel gears 122 arranged to transmit torque to the other of the first and second cutting drum 31, 32. In this figure, the first set 120 of bevel gears 122 and the planetary gear 124 are arranged to transmit torque to the second cutting drum 32. It is, however, to be understood that the first set 120 of bevel gears 122 and the planetary gear 124 could be arranged to transmit torque to the first cutting drum and the second set 120 of bevel gears 122 could be arranged to transmit torque to the second cutting drum 32. The first set 120 of bevel gears 122 may be connected to the motor 110 and to the second cutting drum 32. The first set 120 of bevel gears 122 may comprise a first bevel gear 122’ and a second bevel gear 122”. The second set 120 of bevel gears 122 may comprise a third bevel gear 122’” and a fourth bevel gear 122””. The motor 110 may be vertically mounted to transfer torque to an input shaft connected to the first bevel gear 122’ of the first set 120. The first bevel gear 122’ may thus be connected to the motor 110 and to the second bevel gear 122”. The second bevel gear 122” may be connected to the planetary gear 124. The planetary gear 124 may comprise a sun gear 126, planetary gears 128, a planet carrier 130 and a ring gear 132 according to conventional planetary gears. The second bevel gear 122” may be directly connected to the sun gear 126. The sun gear 126 may be arranged to drive the planet carrier 130 via the planetary gears 128. The planet carrier 130 may be connected to the second cutting drum 32. The planet carrier 130 may also be connected to the third bevel gear 122”’ of the second set 120 of bevel gears 122. The third bevel gear 122”’ may further be connected to the fourth bevel gear 122”” of the second set 120 of bevel gears 122. The fourth bevel gear 122”” may also be connected to the first cutting drum 31 and thereby transmit torque to the first cutting drum 31. Figures 6a-c schematically illustrate details of drum cutter arrangements 10 for carrier vehicles 1 according to examples. The figures show drum cutter arrangements 10 with a drive system 40 as disclosed in Figure 2 but it is to be understood that the drum cutter arrangements 10 may be configured as disclosed in Figure 1, 23, 4a-b or 5a-b.

Figure 6a shows a drum cutter arrangement 10 where the first cutting drum 31 and the second cutting drum 32 are tapered with a decreasing diameter in direction away from the main element 20. Thus, the first and the second cutting drum 31 , 32 are tapered from the proximal end 65 towards the distal end 66. The first and second cutting drum 31, 32 further comprises a convex circumferential wall. In this example, the operational line of the drum cutter arrangement 10 will be convex.

Figure 6b shows a drum cutter arrangement 10 where the first cutting drum 31 and the second cutting 32 comprises a concave circumferential wall. In this example, the operational line of the drum cutter arrangement 10 will be concave.

Figure 6c shows a drum cutter arrangement 10 where the first cutting drum 31 and the second cutting drum 32 comprises an essentially S-shaped circumferential wall with a concave section and a convex section. Typically, the concave section may be at the proximal end 65 and the convex section may be at the distal end 66. In this example, the diameter of the cutting drums 31 , 32 is larger at the distal end 66 than at the proximal end 65. Also, in this example, the operational line will be somewhat wave-shaped.

Figure 7 schematically illustrates a vehicle 1 according to an example. The vehicle 1 comprises a drum cutter arrangement 10 as disclosed in Figure 1, 2, 34a-c, 5 or 6a-c. The vehicle 1 may thus be referred to as a carrier vehicle. The vehicle 1 may be an excavator.

The foregoing description of the examples of the present disclosure is provided for illustrative and descriptive purposes. It is not intended to be exhaustive or to restrict the disclosure to the variants described. Many modifications and variations will obviously be apparent to one skilled in the art. The examples have been chosen and described in order best to explain the principles of the disclosure and its practical applications and hence make it possible for specialists to understand the disclosure for various examples and with the various modifications appropriate to the intended use.

Claims

1. A drum cutter arrangement (10) for a carrier vehicle (1), the drum cutter arrangement (10) comprising: a main element (20) with a longitudinal extension (L); a first and a second rotatable cutting drum (31 , 32) connected to, and arranged on opposite sides of, the main element (20); and a drive system (40) arranged to drive the first and second cutting drum (31, 32), wherein the first cutting drum (31) is rotatable around a first axis (33) and the second cutting drum (32) is rotatable around a second axis (34), wherein the cutting drums (31 , 32) are arranged with the first axis (33) and the second axis (34) inclined in relation to a first plane (P) perpendicular to the longitudinal extension (L) of the main element (20), with an angle (a) between the first axis (33) and the second axis (34).

2. The drum cutter arrangement (10) according to claim 1 , wherein the angle (a) between the first axis (33) and the second axis (34) is within the range of 120- 170 degrees.

3. The drum cutter arrangement (10) according to claim 1 or 2, wherein the drive system (40) is configured to be connectable to a power system of the carrier vehicle (1).

4. The drum cutter arrangement (10) according to any one of the preceding claims, wherein the drive system (40) comprises: a motor (41), and a first gear device (42) connected to the motor (41 ) to transmit torque to the cutting drums (31 , 32).

5. The drum cutter arrangement (10) according to claim 4, wherein the drive system (40) further comprises: two bevel gear sets (70) symmetrically arranged on opposite sides of the first gear device (42), wherein each bevel gear set (70) is connected to the first gear device (42) and to the first and second cutting drum (31, 32) respectively.

6. The drum cutter arrangement (10) according to claim 4, wherein the drive system (40) further comprises: a crown gear device (80) connected to the first gear device (42) and to the first and second cutting drum (31 , 32).

7. The drum cutter arrangement (10) according to any one of claims 1-3, wherein the drive system (40) comprises: at least one motor (44) arranged inside the any one of the cutting drums (31 , 32) to drive the first and second cutting drum (31 , 32).

8. The drum cutter arrangement (10) according to any one of claims 1-3, wherein the drive system (40) comprises: a motor (110); two sets (120) of bevel gears (122); and a planetary gear (124), arranged to transmit torque to the first and second cutting drum (31 , 32).

9. The drum cutter arrangement (10) according to any one of the preceding claims, wherein each cutting drum (31 , 32) is tapered with a decreasing diameter in direction away from the main element (20).

10. The drum cutter arrangement (10) according to claim 9, wherein the first and second cutting drums (31 , 32) are tapered with an angle (y) within the range of 5-30 degrees.

11. The drum cutter arrangement (10) according to any one of claims 1-8, wherein the cutting drums (31 , 32) have a cylindrical shape, a concave shape or a convex shape.

12. A vehicle (1), comprising a drum cutter arrangement (10) according to any one of claims 1-11.

13. The vehicle (1) according to claim 12, wherein the vehicle (1) is an excavator.