A mounted milling unit having a lateral cutting head positioned at an angle to each other and an output gear having beveloid teeth, and a construction machine having such a mounted milling unit.

Abstract

The present invention relates to an attachment milling (attachment cutting) unit comprising a housing with an attachment bracket for attachment to a movable transport arm of a transport device. The housing extends along a longitudinal axis (01). The attachment milling unit further comprises at least one motor (02) and a transmission unit having a drive spur gear (04) whose rotation axis (05) extends perpendicular to the longitudinal axis (01) of the housing. Two transverse cutting heads (06) are mounted on either side of the longitudinal axis (01) of the housing and are driven in rotation by the transmission unit. The transverse cutting heads (06) carry a number of rotating milling bits (07).

Description

Technical Field

[0001] The present invention relates to a mounted milling unit having two transverse cutting heads (Querschneidkoepfen) positioned at an angle to each other. The mounted milling unit comprises a housing having a mounting bracket at the rear end of the mounted milling unit for attachment to a movable conveying arm of a conveying device, preferably of an excavator or a similar construction machine. Further, the mounted milling unit comprises at least one motor and a transmission unit arranged in the housing and coupled on the drive side to the at least one motor. Finally, two transverse cutting heads which are rotationally driven via the transmission unit are attached on both sides of the longitudinal axis of the housing, each transverse cutting head carrying a number of milling bits (Fraesmeissel), and each transverse cutting head has an output shaft which is driven to rotate the transverse cutting head around.

Background Art

[0002] The fields of use of such a mounted milling system are, in particular, waterway construction, road construction, special foundation construction, tunnel construction, or flood control construction. Here, the mounted milling is used, for example, not only for the crushing of sealed surfaces, but also for the demolition of concrete and for the disintegration of specific soil layers and rock layers.

[0003] Excavator-mounted milling cutters are already known, which are formed as lateral cutting head milling cutters and equipped with a round shaft bit (Rundschaftmeisseln) with a hard metal tip as the cutting tool. When using this type of milling cutter, it is usually necessary to rotate the milling cutter so that it reciprocates along the side, thereby breaking the material between the cutting heads. A disadvantage of these milling cutters is that the cutting width is greater than the actual width of the milling head, which has proven to be particularly disadvantageous in waterway construction. A further disadvantage of these milling cutters is the load on the excavator's slewing mechanism, which is always exposed to large torsional and shear forces during milling.

[0004] Excavator-mounted milling cutters are often used for the demolition of soft and medium-hard rocks, such as limestone or gypsum. Here, particularly in gypsum demolition, it is especially important to keep the proportion of fine particles in the milled workpiece as low as possible. With the use of an excavator-mounted milling cutter having a side cutting head that rotates in the demolition wall, the material broken by the front cutting head is undesirably further pulverized by the subsequent cutting head.

[0005] German Patent No. 10041275 (DE10041275B4) describes a milling system for attachment to a hydraulic conveying device, wherein the milling system comprises two or more mounted milling machines of the same or different structure, each having the same or different tool carriers and being individually driven by a hydraulic motor. The individual mounted milling machines are interchangeably arranged via connecting brackets adjacent to each other, front to back, or at angles to each other, at the same or different heights. This is desirable to enable more efficient material dismantling in front of the conveying device. However, this milling system is expensive and not very suitable for, for example, grooving work.

[0006] U.S. Patent No. 7,096,609 describes a so-called trencher fitted with a milling chain. The trencher comprises a screw shaft mounted perpendicular to the direction of travel of the milling chain, which pushes the removed soil out of the dug trench. One drawback here is the limited usability of this machine. The trencher is not suitable for large-scale material demolition in walls. Furthermore, due to its highly realized structure, the trencher is subjected to high mechanical stress. Here, forces are generated not only in the longitudinal direction of the surrounding milling chain, but also perpendicular to the milling chain, particularly when the milling tool strikes an obstacle such as a stone or similar object.

[0007] German Patent Application Publication No. 102008041982 describes a mountable milling system for attachment to a movable conveying arm of a conveying device. The mountable milling system comprises a mountable bracket to which rotating cutting heads are mounted on both sides relative to the longitudinal axis of the mountable bracket. Furthermore, the mountable milling system comprises a circumferential rotary milling chain with a direction of travel that runs parallel to the longitudinal axis of the mountable bracket and extends between both cutting heads. Numerous milling bits are attached to the milling chain and cutting heads, which trace a cylindrical milling outer surface (Fraesmantelflaeche) as the cutting heads rotate. The milling bits of the milling chain form a semi-cylindrical outer surface at the exposed front end of the milling chain. Here, the front reversal line of the milling chain is substantially in a plane tangent to the milling outer surfaces of both cutting heads. Therefore, the contact line between the milling bit of the cutting head and the surface to be milled is right next to the contact line of the milling bit of the milling chain, with no notable gap determined by the width of the mounting bracket in the case of equipment without a milling chain. Conveniently, these contact lines also lie in a common plane. Thus, a continuous milled surface can be machined, thereby eliminating the need for the pendulum lateral movement of the mounting milling system. However, the structure of this system is relatively expensive, and the milling chain in particular is subject to significant wear.

[0008] International Publication No. 2021 / 239225 describes a drum cutting device for transport vehicles. The drum cutting device comprises a main element having a longitudinal extension; first and second rotatable cutting drums connected to the main element and located on the opposite side of the main element; and a drive system arranged to drive the first and second cutting drums. The first cutting drum is rotatable about a first axis, and the second cutting drum is rotatable about a second axis. With respect to a first plane, the first and second axes are perpendicular to the longitudinal extension of the main element, and an angle is formed between the first and second axes. A complex drive is formed to drive both cutting drums. The main element has at least one central spur gear having two side-mounted bevel gears that interact with two further bevel gears associated with the cutting drums. Thus, two sets of bevel gears (double bevel gear pairs) from two bevel gears each are arranged symmetrically on the opposite side of the central spur gear. Therefore, the main components consist of three gears: a central spur gear and two bevel gears on the sides, the latter of which drive further bevel gears on the shaft of the cutting drum. This structure is very expensive and prone to repairs. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] German Patent No. 10041275 (DE10041275B4) [Patent Document 2] U.S. Patent No. 7,096,609 [Patent Document 3] German Patent Application Publication No. 102008041982 Specification [Patent Document 4] International Publication No. 2021 / 239225 [Overview of the project] [Problems that the invention aims to solve]

[0010] The object of the present invention is to provide an improved mountable milling unit for attachment to a movable conveying arm of a conveying device, starting from the prior art, which can be manufactured more easily and inexpensively, and at the same time enables the production of a substantially continuous milled surface, and for that purpose does not require the constant pendulum movement of the support arm and the mountable milling unit fixed thereto. In particular, it is desirable that the drive transmission be implemented inexpensively and robustly.

[0011] Furthermore, it is desirable that the present invention provide an improved construction machine having such a mountable milling unit. [Means for solving the problem]

[0012] This problem is solved by the mountable milling unit described in claim 1 or the construction machine described in claim 11.

[0013] In the mounted milling unit according to the present invention, both output shafts of the lateral cutting head are positioned at an angle to each other, and these output shafts form an acute angle with the longitudinal axis of the housing on the side not facing the mounting bracket. This widens the angle between the two output shafts of the lateral cutting head to 135° to 175°, preferably 160° to 170°, on the side facing the front end of the mounted milling unit. Therefore, the lateral cutting heads are inclined relative to each other, and thus the milling surfaces drawn by the rotating milling heads are closer to each other on the forward-facing side of the lateral cutting heads than on the rear-facing side. In particular, the distance between the drawn milling surfaces is smaller than the width of the housing on the rear-facing side of the lateral cutting heads, and preferably less than half the width of the housing of the mounted milling unit. Therefore, in preferred cases, the distance between the drawn milling surfaces is only a few centimeters.

[0014] Furthermore, the present invention is characterized in that the transmission unit comprises a drive spur gear whose axis of rotation runs perpendicular to the longitudinal axis of the housing. Thus, the headlines of the individual teeth of the drive spur gear run laterally with respect to the longitudinal axis of the housing, and therefore, preferably, parallel to the milling contact line drawn when the lateral cutting head rotates at the front end of the mounted milling unit. In addition, output gears (also called conical spur gears) having beveroid teeth are mounted on both output shafts of the lateral cutting head, and the beveroid teeth of each output gear directly engage with the corresponding portions of the spur teeth of the drive spur gear.

[0015] In this way, the present invention minimizes the area between the lateral cutting heads that the milling heads cannot reach, thereby eliminating the need for a milling chain running between the cutting heads and enabling the use of a stable, low-wear, and low-maintenance transmission equipped with fewer gears.

[0016] By utilizing beveloid teeth, a double bevel gear set is not required, and therefore only one spur gear with straight teeth and two beveloid gears directly driven by the straight teeth are needed, resulting in a significantly simpler and, in particular, more compact structure compared to conventional technology.

[0017] Preferably, each of the two output gears is further provided with internal teeth that are fitted onto the external teeth of the toothed connecting shaft. The connecting shaft is the output shaft External teeth This is connected to the internal teeth of an output gear that carries beveloid teeth. The output shaft is preferably housed in an output housing having two tapered roller bearings. Then, a right-side or left-side lateral cutting head is mounted on the output shaft, respectively.

[0018] According to the modified embodiment, the transmission unit comprises two partial drive spur gears positioned parallel to each other, with their common axis of rotation running perpendicular to the longitudinal axis of the housing. In this case as well, output gears having beveloid teeth are mounted on both output shafts, with the beveloid teeth of each output gear engaging with the spur teeth of one of the drive spur gears.

[0019] Particularly preferably, the milling bit of each lateral cutting head traces a frustoconical outer surface of the milling cutter as it rotates. In particular, both frustoconical outer surfaces of the milling cutter are in contact with a common milling contact plane at the front end of the mounted milling unit; that is, the milling contact line, partially defined by both adjacent lateral cutting heads, preferably extends into a common plane perpendicular to the longitudinal axis of the housing.

[0020] An advantageous embodiment is characterized in that the motor is a hydraulic motor, preferably fixed to the side surface of the housing, and alternatively may be housed within the housing. According to a further modified embodiment, the mounted milling unit may comprise two hydraulic motors, preferably fixed to the opposite side surface of the housing. Both hydraulic motors can be used together to drive a drive spur gear, or they can drive two drive gears that are rotatable independently of each other. In the latter case, both lateral cutting heads are driven independently of each other, which allows for separate rotational speed control and can be used, for example, to rotate one of the lateral cutting heads slower than the other or even to stop it completely under certain conditions. Thus, curved grooves can be milled more easily and with less wear on the lateral cutting heads.

[0021] Preferably, the transmission unit comprises at least one drive pinion that drives and engages with a drive spur gear, either directly or indirectly via further gears.

[0022] Further advantages and details of the present invention will become apparent from the following description of the preferred embodiments with reference to the drawings.

Brief Description of the Drawings

[0023] [Figure 1] FIG. 8 is a basic view of a first embodiment of a mounting type milling unit according to the present invention. [Figure 2] FIG. 11 is a cross-sectional view of a second embodiment of the mounting type milling unit.

Mode for Carrying Out the Invention

[0024] FIG. 1 shows a basic view of a mounting type milling unit. In this figure, for the sake of simplification, the housing and the mounting bracket used to fix the mounting type milling unit to a support arm such as an excavator are not shown. However, the housing not shown has a longitudinal extension represented by the longitudinal axis 01. In this embodiment, the mounting type milling unit has a high torque motor 02 attached to one side of the housing and preferably powered by the hydraulic system of an excavator. Alternatively, an electric motor may be used.

[0025] Inside the housing, a transmission unit driven by the motor 02 is arranged. In the illustrated embodiment, the transmission unit includes a drive pinion 03 directly flange-connected on the motor shaft. Further, the transmission unit includes a drive spur gear 04, and its rotation axis 05 runs perpendicular to the longitudinal axis 01 of the housing.

[0026] The mounted milling unit has two lateral cutting heads 06 that are rotationally driven via a transmission unit and are mounted on both sides of the longitudinal axis 01 of the housing, and each head carries a number of milling bits 07, the milling bits being shown only on the lateral cutting head located on the right side in the figure. While the lateral cutting heads 06 are rotating, these milling bits 07 trace a frustoconical outer surface 08, which is represented by a dashed line. Each lateral cutting head 06 rests on a driven output shaft 09, around which the lateral cutting head rotates. Both output shafts 09 of the lateral cutting heads are positioned at an angle to each other. Preferably, these output shafts 09 are diverged by an angle in the range of 150° to 170°. The diverging angle is preferably selected so that the frustoconical outer surfaces 08 are in a common plane perpendicular to the longitudinal axis 01 of the housing at their outer surfaces or contact lines facing the milling surface. In other words, the output shaft 09 forms an acute angle, preferably about 75° to 85°, with the longitudinal axis 01 of the housing at its front end.

[0027] To rotate the lateral cutting head, output gears 10 having beveloid teeth are mounted on each output shaft 09, and the beveloid teeth of each output gear 10 directly engage with the corresponding portion of the spur teeth of the drive spur gear 04.

[0028] Figure 2 shows a cross-sectional view of a modified embodiment of the mounted milling unit. Here, it can be clearly seen that the beveroid teeth of the output gear 10 directly engage with the corresponding lateral regions of the straight teeth of the drive gear 04. On the opposite side of the circumference of the drive gear 04, the drive pinion 03 engages with the central region of the teeth. This arrangement has the advantage of applying a uniform load across the tooth surfaces of the drive gear, and therefore resulting in uniform wear. While the driving force is introduced into the central region of the teeth, this driving force is released to the output gear 10 in the lateral regions of the teeth that are not meshing with the drive pinion 03. However, the special beveroid teeth ensure that the teeth do not change along the axial direction of the drive gear, i.e., along the individual tooth surfaces, thereby allowing for the easy and inexpensive manufacture of the drive gear. [Explanation of symbols]

[0029] 01...Longitudinal axis of the housing, 02...Motor, 03...Drive pinion, 04...Drive spur gear, 05...Rotation axis of the drive spur gear, 06...Lateral cutting head, 07...Milling bit, 08...Outer surface of the milling cutter, 09...Output shaft of the lateral cutting head, 10...Output gear

Claims

1. - A housing having a mounting bracket at the rear end of a mounting type milling unit for attachment to a movable transfer arm of a transfer device, wherein the housing extends along a longitudinal axis (01), - At least one motor (02) and - A transmission unit is located within the housing, coupled to the at least one motor (02) on the drive unit side, and includes a drive spur gear (04) whose rotation axis (05) runs perpendicular to the longitudinal axis (01) of the housing, - Two lateral cutting heads (06) mounted on both sides of the longitudinal axis (01) of the housing and carrying a number of milling bits (07), which are rotationally driven via the transmission unit, wherein each lateral cutting head (06) has an output shaft (09) that drives the lateral cutting head (06) to rotate around it, and both output shafts (09) of the lateral cutting heads (06) are positioned at an angle to each other, forming an acute angle with the longitudinal axis (01) of the housing on the side not facing the mounting bracket, In a mountable milling unit, Each output gear (10) having beveloid teeth is mounted on the output shaft (09), The beveloid teeth of each output gear (10) directly engage with the corresponding portion of the spur teeth of the drive spur gear (04), Each of the output gears (10) is provided with internal teeth fitted onto the external teeth of the output shaft (09). A mountable milling unit characterized by the following features.

2. The mounted milling unit according to claim 1, characterized in that the drive spur gear of the transmission unit is divided into two partially driven spur gears positioned parallel to each other, their common axis of rotation running perpendicular to the longitudinal axis (01) of the housing, and the beveroid teeth of the output gears (10) mounted on the output shaft (09) engage with the spur teeth of one of the partially driven spur gears.

3. The mounting type milling unit according to claim 1, characterized in that the milling bit (07) of each lateral cutting head (06) traces a frustoconical outer surface (08) of the milling cutter when it rotates.

4. The mountable milling unit according to claim 3, characterized in that both of the frustoconical outer surfaces (08) of the milling cutter are in contact with a common milling cutter contact plane at the front end of the mountable milling unit.

5. The mounting type milling unit according to claim 1, characterized in that the motor (02) is a hydraulic motor fixed to the side surface of the housing.

6. The mounting type milling unit according to claim 1, characterized in that the mounting type milling unit comprises two hydraulic motors fixed to the side surface opposite to the housing.

7. The mounting milling unit according to claim 1, characterized in that the transmission unit comprises at least one drive pinion (03) that drives and engages with the drive spur gear (04) directly or indirectly via further gears.

8. The mounting type milling unit according to claim 1, characterized in that, on the side facing the front end of the mounting type milling unit, the angle between both output shafts (09) of the lateral cutting head (06) is widened to a range of 150° to 170°.

9. The mounting type milling unit according to claim 3, characterized in that the distance between the outer surfaces (08) of the milling cutter drawn by the lateral cutting head (06) is smaller than the width of the housing on the side facing the rear of the lateral cutting head.

10. A construction machine having a movable transport arm having a fixing means for a mountable unit, characterized in that a mountable milling unit according to any one of claims 1 to 8 is detachably attached to the fixing means.

11. The construction machine according to claim 10, characterized in that the construction machine is formed as an excavator.

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