DE102021106129A1 - Mobile work machine, in particular an excavator, with a vehicle frame and a lifting arm - Google Patents

Abstract

A mobile work machine (1) with a vehicle frame and with at least one lifting arm (2) for raising and/or lowering a tool holding device, a drive unit for driving at least one drive element (5) such as a drive wheel or a drive chain (5) being provided , wherein at least the tool holding device is designed to hold a releasably connectable working tool, at least one lifting cylinder (3) being arranged on the lifting arm (2), wherein between a lifting arm holding unit (7) and a first lifting arm end section (9) of the lifting arm (2) a first holding shaft (16) for pivoting the lifting arm (2) and between the lifting arm holding unit (7) and the lifting cylinder (3) at least one first lever element (12) are arranged, with between the lifting arm holding unit (7) and the first lever element (12) at least one second holding shaft (13) and at least one first lever shaft (14) provided between the first lever element (12) and the lifting cylinder (3). n, with at least one second lever element (11) being arranged between the lifting arm (2) and the first lever shaft (12) or the lifting cylinder (3), which improves the performance and/or stability of the working machine (1) or the Lift arm (2) at least partially improved. This is achieved in that the first lifting arm end section (9) of the lifting arm (2) has at least one receiving recess arranged between two arm cheek sections (10) for receiving at least one end of the second lever element (11), the two arm cheek sections (10) for receiving at least the second lever shaft (11) are formed.

Description

The invention relates to a mobile work machine, in particular an excavator, wheel loader, tractor, telehandler or the like, with a vehicle frame and with at least one lifting arm for raising and/or lowering a tool holding device according to the preamble of claim 1.

State of the art

Various excavators or mobile working machines with a lifting arm for lifting and lowering loads or working tools are known. For construction work, shovel excavators of various sizes and variants are used, for example, to move earth or gravel, sand or the like. Here, by means of a hydraulic cylinder, a shovel or spoon is attached to the lifting arm so that it can be moved and which can also be exchanged, for example to use a hydraulic impact hammer to smash concrete or rocks on the lifting arm.

Various rear excavators or lifting arms or the like are also known in agriculture, which can be attached to a tractor or its so-called three-point hydraulic system and used, for example, by means of an excavator bucket or a grab cable to move soil, manure, silage or the like be able.

As a result, the lifting arm is connected to a wide variety of lifting arm holding units/elements directly via an essentially horizontally aligned, first pivot axis on/to the vehicle frame and/or indirectly to an additional lifting arm holding unit arranged between the lifting arm and the actual frame, with e.g. the above-mentioned three-point hydraulic system or a so-called “pivoting console” with a second pivoting axis aligned essentially vertically, for example in the case of so-called “mini-excavators” or the above-mentioned rear excavators.

From the EP 0 887 475 B1 however, a large excavator is already known in which the lifting arm is rotatably mounted directly on the supporting frame, but the hydraulic cylinder is pivotally mounted on a connecting lever which in turn is pivotally mounted on the vehicle frame. In addition, the hydraulic cylinder and the connecting lever or their common axis of rotation is pivotably attached to the lifting arm via a second connecting lever.

This lever construction or this four-axis swivel mechanism enables a reduced transport height for large excavators with long lifting arms when they are transported on a low-loader or the like on roads. This should make it possible to transport the excavators, e.g. under electrical lines or through tunnels, etc. However, the reduction of the transport height on a transport vehicle is irrelevant in the case of so-called mini excavators or backhoes for tractors, since these can usually also be driven through tunnels etc. on low loaders etc.

When working, mini excavators can lower the lifting arms accordingly, so that the maximum excavator height/size is determined not by the lifting arm but by the driver's cab. For this purpose, they often have collapsible or foldable driver's cabs, e.g. to temporarily lower the maximum vehicle height for driving through a door frame or a garage door etc.

Object and advantages of the invention

In contrast, the object of the invention is to propose a mobile work machine, in particular an excavator, wheel loader, tractor, telehandler or the like, with a vehicle frame and with at least one lifting arm for raising and/or lowering a tool holding device, which improves the performance and/or stability of the work machine or .of the lift arm at least partially improved.

Starting from a mobile work machine of the type mentioned at the outset, this object is achieved by the features of claim 1 . Advantageous embodiments and developments of the invention are possible as a result of the measures mentioned in the subclaims.

Accordingly, a mobile working machine according to the invention is characterized in that the first lifting arm end section of the lifting arm has at least one receiving recess arranged between two arm cheek sections for receiving at least one end of the second lever element, the two arm cheek sections being designed to receive at least the second lever shaft.

With the help of the two arm cheek sections or the receiving recess according to the invention, a particularly compact and stable construction of the lifting arm is possible. In addition, the vehicle driver can, for example, look through between the two arm cheek sections or the receiving recess, so that his view or the possibility of checking the work tool or the work site is significantly improved.

In addition, the arrangement of the second lever element between the two arm cheek sections advantageously allows the second lever element to be mounted on both sides of the lifting arm. In this way, a particularly stable, rigid mounting of the second bearing shaft or the second lever element can be implemented. This is of great advantage, especially with the high loads/forces in excavators or the like.

The bearing width of the lifting arm according to the invention does not have to be widened either, so that, for example, in systems with swivel brackets or the like according to the invention, there are no restrictions in the swivel angle/range.

In contrast, the EP 0 887 475 B1 between the lifting cylinder and the lifting arm, two individual levers or connecting pieces arranged on both sides of the lifting arm and mounted on one side. Thus, not only is a cantilever bearing required, but also a comparatively wide construction with comparatively long bearing shafts.

The second lever element is preferably arranged at least partially within the lifting arm and/or between the two arm cheek sections and/or the two arm cheek sections are arranged next to one another in the horizontal direction, with the receiving recess being aligned in the vertical direction. This enables a particularly stable and compact design.

In a preferred embodiment of the invention, the first and second support shafts and the first and second lever shafts are aligned in the horizontal direction. An advantageous four-point mechanism is hereby realized, by means of which the lifting arm and the lifting cylinder can be pivoted.

In an advantageous variant of the invention, at least one vertically aligned bearing shaft for horizontal pivoting of the lifting arm is arranged between the vehicle frame and the lifting arm holding unit. This increases the flexibility of the lifting arm, which namely can be pivoted about this vertical axis of rotation and thus the working area can be increased.

At least one cantilever arm is advantageously arranged between the lifting arm and the tool holding device, with at least one cantilever shaft being arranged in particular between the lifting arm and the cantilever arm. In this way, another arm can be pivoted in an advantageous manner, which increases the range of the work machine when the work location is fixed.

In a particular development of the invention, the second lever element comprises at least two lever cheeks that accommodate the first lever shaft, with the lifting cylinder being arranged at least partially between the two lever cheeks, and/or the first lever element comprises at least two cheeks that accommodate the first lever shaft, with the lifting cylinder is arranged at least partially between the two cheeks, in particular the two lever cheeks of the second lever element are arranged at least partially between the two cheeks of the first lever element. In this way, the lifting cylinder/hydraulic cylinder and/or the second lever element can be mounted on both sides in an advantageous manner, so that a particularly stable, rigid mounting is implemented. This is of great advantage, especially with the high loads/forces in excavators or the like.

• - Vorteilhafterweise ist ein erster Abstand zwischen der ersten Haltewelle und der zweiten Hebelwelle kleiner als ein zweiter Abstand zwischen der zweiten Haltewelle und der ersten Hebelwelle.
• - Das zweite Hebelelement hat in vorteilhafter Weise eine doppelt geschwungene Form aufweisen bzw. ist S-förmig ausgebildet.
• - Die zweite Hebelwelle vollzieht in vorteilhafter Weise im Betrieb der Arbeitsmaschine, d.h. in einem Bewegungszyklus von einer unteren Endposition des Hubarms zu einer oberen Endposition des Hubarms und auch umgekehrt jeweils eine bogenförmige Bewegung, die zumindest abschnittsweise um die erste Haltewelle herum verläuft. Das Gleiche gilt für das zweite Hebelelement, das sich zumindest bereichsweise um die erste Haltewelle herum bewegt.
• - Vorteilhafterweise schneiden weder die zweite Hebelwelle, noch das zweite Hebelelement die Achse der ersten Haltewelle.
• - Der Hubarm ist in vorteilhafter Weise vor der Kabine, insb. mittig, angeordnet. Im Gegensatz zu vielen Groß-Baggern, bei denen der Hubarm seitlich der Kabine positioniert sein muss, um dessen Verschwenkung realisieren zu können, insb. bei sogenannten „Hüllkreisbagger“, wobei derartige Groß-Bagger den sog. Oberwagen drehen können, ohne dass ein Bauteil des Oberwagens über die Außenmaße des sog. Unterwagens hinaus ragt. Bei einer besonderen, alternativen Variante der Erfindung kann jedoch der Hubarm auch mittig angeordnet werden.
• - Der Hubarm ist gemäß einer vorteilhaften Ausführungsform im Wesentlichen mittig an einer Querseite eines sog. „Oberwagens“ der Arbeitsmaschine bzw. eines Bagger angeordnet, wobei der Oberwagen um eine im Wesentlichen vertikal ausgerichtete Drehachse, nicht näher dargestellt, rotierbar auf einem mobilen, sog. „Unterwagen“, insb. mit dem Ketteantrieb oder Laufradeinheit, positioniert ist. Der Arm ist vor einem Arbeitsplatz eines Bedieners angeordnet. Die Verschwenkung des Arms nach oben bzw. hinten ist gemäß dieser Ausführungsform deshalb durch den Sicherheitsbereich des Bedieners bzw. einer Kabine begrenzt. Der Arm steht deshalb in seiner oberen Endposition zumindest bereichsweise im Wesentlichen senkrecht. Das heißt, dass sich gemäß dieser Ausführungsform die Längsachse des Fußendes des Hubarms in einer oberen Endposition im Wesentlichen in der Senkrechten erstreckt.

In general, according to the invention, the following advantageous features or measures can be implemented individually and/or in combination with one another:

• - Advantageously, a first distance between the first support shaft and the second lever shaft is smaller than a second distance between the second support shaft and the first lever shaft.
• - The second lever element advantageously has a double curved shape or is S-shaped.
• The second lever shaft advantageously performs an arcuate movement during operation of the working machine, ie in a movement cycle from a lower end position of the lifting arm to an upper end position of the lifting arm and vice versa, which runs at least in sections around the first holding shaft. The same applies to the second lever element, which moves at least in certain areas around the first holding shaft.
• - Advantageously, neither the second lever shaft nor the second lever element intersect the axis of the first support shaft.
• - The lifting arm is advantageously arranged in front of the cabin, especially in the middle. In contrast to many large excavators, in which the lifting arm must be positioned to the side of the cabin in order to be able to swivel it, especially in the case of so-called "enveloping circle excavators", whereby such large excavators can rotate the so-called superstructure without a component of the superstructure protrudes beyond the outer dimensions of the so-called undercarriage. In a special, alternative variant of the invention, however, the lifting arm can also be arranged in the middle.
• - According to an advantageous embodiment, the lifting arm is arranged essentially in the middle on a transverse side of a so-called "upper carriage" of the work machine or an excavator, the upper carriage being rotatable about a substantially vertically aligned axis of rotation, not shown in detail, on a mobile, so-called "Undercarriage", especially with the chain drive or wheel unit, is positioned. The arm is arranged in front of an operator's work station. According to this embodiment, the pivoting of the arm upwards or backwards is therefore limited by the safety area of the operator or a cabin. In its upper end position, the arm is therefore essentially vertical, at least in certain areas. This means that according to this embodiment the longitudinal axis of the foot end of the lifting arm extends essentially in the vertical in an upper end position.

It has surprisingly been shown in initial tests or investigations with a work machine according to the invention that an improved/increased lifting force can be realized in comparison to the previously customary arrangements or mechanisms according to the invention. In the upper lifting/lifting range, i.e. when the lifting arm is raised, there is a particularly high or large torque, e.g. approx. 50% to 60% compared to lifting arms that have been customary up to now.

This advantageously means that with approximately the same dimensioning of the lifting cylinder, in particular the hydraulic cylinder and/or the lifting arm, i.e. without reinforcing the structure or wall etc., greater loads can be carried/lifted, especially in the upper area. Accordingly, greater performance of the mobile working machine is realized in an energy-saving and thus environmentally friendly manner. This is achieved with almost the same/comparable weight of the lifting arm arrangement or the entire boom, so that, for example, no larger drive motor and/or more heavily designed/dimensioned hydraulics are required. This enables a cost-effective, economical implementation of the invention, especially retrofitting of previous mobile working machines such as excavators or the like.

In addition to the greatly improved lifting power in comparison to systems customary up to now, the now also lower pressure level of the lifting cylinder, which has often carried load pressure up to now, can have a positive effect on the energy balance of the hydraulic system and thus also on the overall performance, productivity and economy of the mobile working machine according to the invention.

In the first tests, for example, a mini excavator could lift and transport a vibrating plate, which up to now could not lift and transport this weight without a design according to the invention. Accordingly, according to the invention, the usability or the performance of the corresponding mini excavator in the work operation has been significantly improved or expanded.

character list

An embodiment of the invention is shown in the drawing and is explained in more detail below with reference to the figures.

• 1 eine schematische Darstellung eines Mini-Baggers mit Hubarm gemäß der Erfindung in mittlerer Stellung,
• 2 ein schematischer, vergrößerter und teilweise geschnittener Ausschnitt des Hubarmes gemäß 1,
• 3 eine schematische Darstellung des Mini-Baggers gemäß 1 mit Hubarm in oberer Stellung und
• 4 eine schematische Darstellung des Mini-Baggers gemäß 1 mit Hubarm in unterer Stellung.

In detail shows:

• 1 a schematic representation of a mini excavator with lifting arm according to the invention in the middle position,
• 2 a schematic, enlarged and partially sectioned section of the lifting arm according to FIG 1 ,
• 3 a schematic representation of the mini-excavator according to 1 with the lift arm in the up position and
• 4 a schematic representation of the mini-excavator according to 1 with lift arm in lower position.

A so-called mini-excavator 1 is shown schematically in the figures, which has a lifting arm 2 that can be raised and lowered, wherein the lifting arm 2 can be actuated or adjusted/pivoted with a hydraulic cylinder 3 .

In a generally customary manner, the mini excavator 1 comprises a driver's cab 4 and, as drive elements, two chain drives 5 and an optional clearing blade 6.

In the mini excavator 1 shown, the lifting arm 2 is arranged/mounted on a so-called swivel bracket 7 . With the help of the swivel bracket 7, which can be provided as an option and is already widely used, which has a vertically aligned swivel axis 8 (cf. 2 ), the lifting arm 2 can be pivoted about the pivot axis 8 in the horizontal direction, ie to the right and/or left. This increases the flexibility and usability of the mini excavator 1.

The swivel bracket 7 or lifting arm holding unit 7 can also be an integral part of a vehicle frame or so-called “superstructure” of an excavator. A swivel bracket 7 does not necessarily have to be present.

According to the invention, the lifting arm 2 has two cheeks 10 at a lower foot end 9, between which a connecting rod 11 is rotatably mounted. In addition, a coupling rod 12 is arranged between the hydraulic cylinder 3 and the swivel bracket 7, so that a particularly compact and stable arrangement/mounting is realized.

It's in right now 2 , in which, among other things, the articulated rod 11 is shown in section, it can be seen that a total of four axes of rotation 13 to 16 or shafts 13 to 16 are provided, around which or with which the lifting arm unit or the lifting arm 2 and the hydraulic cylinder 3 as well as the rods 11 , 12 are pivotably mounted.

The link rod 11 in turn has in its lower region a fork, which is not shown in more detail merely for reasons of clarity, which surrounds the hydraulic cylinder or between which it is arranged. In addition, another fork of the coupling rod 12 surrounds this fork of the connecting rod 11 in the area of the axis/shaft 14, so that a particularly compact and stable arrangement/bearing is realized.

The axis/shaft 10 for pivoting the connecting rod 11 is advantageously arranged (substantially) parallel to the axis/shaft 16 for pivoting the lifting arm 2 .

In addition, the two axes/shafts 13, 14 of the coupling rod 12 are aligned/arranged (substantially) parallel to one another. It is precisely by means of the coupling rod 12 that advantageous lever ratios are achieved in the upper lifting area of the lifting arm 2 (cf. 3 ), so that particularly large torques or lifting forces can be achieved here.

In addition, a tool arm 17 is arranged pivotably on the lifting arm 2, to which a detachably connectable or replaceable tool (not shown) can be attached in a known manner.

• - Vorteilhafterweise ist der Abstand zwischen der 1. Haltewelle 16 und der 2. Hebelwelle 15 (in allen Positionen des Hubarms 2) geringer, als der Abstand zwischen der 2. Haltewelle 13 und der 1. Hebelwelle 14.
• - Das 2. Hebelelement 11 hat in vorteilhafter Weise eine doppelt geschwungene Form bzw. ist S-förmig.
• - Die 2. Hebelwelle 15 vollzieht in vorteilhafter Weise im Betrieb der Arbeitsmaschine 1, d.h. in einem Bewegungszyklus von einer unteren Endposition des Hubarms 2 (vgl. 4) zu einer oberen Endposition des Hubarms 2 (vgl. 3) eine bogenförmige Bewegung, die zumindest abschnittsweise um die 1. Haltewelle 16 herum verläuft. Das Gleiche gilt für das 2. Hebelelement 11, das sich zumindest bereichsweise um die 1. Haltewelle 16 herum bewegt.
• - Vorteilhafterweise schneiden weder die 2. Hebelwelle 15 noch das 2. Hebelelement 11 die Achse der 1. Haltewelle 16.
• - Der Arm 2 ist vor der Kabine 4, insb. mittig, angeordnet. Im Gegensatz zu vielen Groß-Baggern, wo der Arm 2 seitlich der Kabine 4 positioniert sein muss, um die Verschwenkung wie in 1 erreichen zu können, insb. bei sogenannten „Hüllkreisbagger“, wobei derartige Groß-Bagger den sog. Oberwagen drehen können, ohne dass ein Bauteil des Oberwagens über die Außenmaße des sog. Unterwagens hinaus ragt. Der Bagger kann so auch in extrem engen Baustellen arbeiten. Als besondere, alternative Variante hierzu kann jedoch der Hubarm 2 auch mittig angeordnet werden.
• - Der Arm 2 ist gemäß der dargestellten Ausführungsform im Wesentlichen mittig an einer Querseite eines sog. „Oberwagens“ eines Bagger angeordnet, wobei der Oberwagen um eine im Wesentlichen vertikal ausgerichtete Drehachse, nicht näher dargestellt, rotierbar auf einem mobilen, sog. „Unterwagen“, insb. mit dem Ketteantrieb 5, positioniert ist. Der Arm 2 ist vor einem Arbeitsplatz eines Bedieners angeordnet. Die Verschwenkung des Arms 2 nach oben bzw. hinten ist gemäß der dargestellten Ausführungsform deshalb durch den Sicherheitsbereich des Bedieners bzw. einer Kabine begrenzt. Der Arm 2 steht deshalb in seiner oberen Endposition zumindest bereichsweise im Wesentlichen senkrecht. Das heißt, dass sich gemäß der dargestellten Ausführungsform die Längsachse des Fußendes 9 des Hubarms 2 in einer oberen Endposition im Wesentlichen in der Senkrechten erstreckt.

In general, according to the invention, the following advantageous features and measures can be implemented individually and/or in combination with one another:

• - Advantageously, the distance between the 1st support shaft 16 and the 2nd lever shaft 15 (in all positions of the lift arm 2) is less than the distance between the 2nd support shaft 13 and the 1st lever shaft 14.
• - The second lever element 11 advantageously has a double curved shape or is S-shaped.
• - The 2nd lever shaft 15 takes place in an advantageous manner during operation of the working machine 1, ie in a movement cycle from a lower end position of the lifting arm 2 (cf. 4 ) to an upper end position of the lifting arm 2 (cf. 3 ) an arcuate movement, which runs at least in sections around the first holding shaft 16 . The same applies to the second lever element 11, which moves at least in certain areas around the first holding shaft 16.
• - Advantageously, neither the 2nd lever shaft 15 nor the 2nd lever element 11 intersect the axis of the 1st support shaft 16.
• - The arm 2 is in front of the cabin 4, especially in the middle. In contrast to many large excavators, where the arm 2 must be positioned to the side of the cab 4 in order to pivot as in 1 to be able to achieve, esp. The excavator can also work in extremely narrow construction sites. As a special, alternative variant to this, however, the lifting arm 2 can also be arranged in the middle.
• - According to the illustrated embodiment, the arm 2 is arranged essentially centrally on a transverse side of a so-called "upper carriage" of an excavator, the upper carriage being rotatable about an essentially vertically aligned axis of rotation, not shown in detail, on a mobile, so-called "undercarriage". , Esp. With the chain drive 5, is positioned. The arm 2 is arranged in front of an operator's work station. According to the illustrated embodiment, the pivoting of the arm 2 upwards or backwards is therefore limited by the safety area of the operator or a cabin. The arm 2 is therefore in its upper end position, at least in some areas, essentially vertical. This means that according to the illustrated embodiment the longitudinal axis of the foot end 9 of the lifting arm 2 extends substantially in the vertical in an upper end position.

Reference List

1

mini excavator

2

lift arm

3

hydraulic cylinder

4

driver's cabin

5

chain drive

6

blade

7

swivel console

8th

pivot axis

9

foot end

10

cheek

11

pole

12

pole

13

axle/shaft

14

axle/shaft

15

axle/shaft

16

axle/shaft

17

tool arm

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 0887475 B1 [0005, 0014]

Claims (10)

Mobile work machine (1), in particular an excavator (1), wheel loader, tractor, telehandler or the like, with a vehicle frame and with at least one lifting arm (2) for raising and/or lowering a tool holding device, with a drive unit for driving at least one drive element (5 ) such as a drive wheel or a drive chain (5) is provided, with at least the tool holding device being designed to hold a detachably connectable working tool, in particular a shovel, gripping shovel, fork tines, gripping fork or the like, with at least one lifting cylinder (3 ), In particular hydraulic cylinder (3), is arranged, wherein at least one lifting arm holding unit (7) for holding / storing the lifting arm (2) and / or the lifting cylinder (3) is provided, wherein between the lifting arm holding unit (7) and a first lifting arm End section (9), in particular the foot end (9), of the lifting arm (2) has a first holding shaft (16) for pivoting the lifting arm (2) and between At least one first lever element (12) is arranged between the lifting arm holding unit (7) and the lifting cylinder (3), with at least one second holding shaft (13) between the lifting arm holding unit (7) and the first lever element (12) and between the first lever element (12 ) and the lifting cylinder (3) at least one first lever shaft (14) is provided, with at least one second lever element (11) being arranged between the lifting arm (2) and the first lever shaft (12) or the lifting cylinder (3), with between the At least one second lever shaft (15) is arranged between the second lever element (11) and the lifting arm (2), characterized in that the first lifting arm end section (9) of the lifting arm (2) has at least one receiving recess arranged between two arm cheek sections (10) for receiving at least one end of the second lever element (11), the two arm cheek sections (10) being designed to receive at least the second lever shaft (15). working machine claim 1 , characterized in that the second lever element (11) is arranged at least partially within the lifting arm (2) and/or between the two arm cheek sections (10). Working machine according to one of the preceding claims, characterized in that the two arm cheek sections (10) are arranged next to one another in the horizontal direction, so that the receiving recess is aligned in the vertical direction. Working machine according to one of the preceding claims, characterized in that the first and second holding shafts (16, 13) and the first and second lever shafts (14, 15) are aligned in the horizontal direction. Working machine according to one of the preceding claims, characterized in that at least one vertically aligned bearing shaft (8) for horizontal pivoting of the lifting arm (2) is arranged between the vehicle frame and the lifting arm holding unit (7). Working machine according to one of the preceding claims, characterized in that at least one cantilever arm (17) is arranged between the lifting arm (2) and the tool holding device. Working machine according to one of the preceding claims, characterized in that at least one cantilever shaft is arranged between the lifting arm (2) and the cantilever arm (17). Working machine according to one of the preceding claims, characterized in that the second lever element (11) comprises at least two lever cheeks receiving the first lever shaft (14), the lifting cylinder (3) being arranged at least partially between the two lever cheeks. Working machine according to one of the preceding claims, characterized in that the first lever element (12) comprises at least two cheeks receiving the first lever shaft (14), the lifting cylinder (3) being arranged at least partially between the two cheeks. Working machine according to one of the preceding claims, characterized in that the two lever cheeks of the second lever element (11) are arranged at least partially between the two cheeks of the first lever element (12).

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