Self-propelled work machine

Abstract

A self-propelled work machine includes an undercarriage provided with drive wheels driven by a drive device. An upper structure is rotatably mounted on the undercarriage. A drive unit is arranged in the undercarriage and a boom for a work tool is mounted on the undercarriage. The drive unit drives a power generator that is a power source for an electric motor arranged in the upper structure, the electric motor being the drive device for the drive wheels arranged on the undercarriage.

Claims

1. A self-propelled work machine comprising: an undercarriage provided with drive wheels; an upper structure rotatably mounted on the undercarriage; an electric motor arranged in the upper structure driving said drive wheels provided on said undercarriage; a drive unit arranged in the upper structure; a boom mounted on the upper structure; and a power generator driven by the drive unit, said power generator providing power to the electric motor to drive said drive wheels provided on said undercarriage.

2. The self-propelled work machine according to claim 1, in which a central shaft that is driven by the electric motor and whose axis coincides with an axis of rotation (A) of the upper structure.

3. The self-propelled work machine according to claim 2, in which the central shaft is connected to a gearing that is arranged in the undercarriage and via which the drive wheels are driven.

4. The self-propelled work machine according to claim 2, in which the central shaft penetrates a revolving bearing collar via which the upper structure is rotatably mounted on the undercarriage.

5. The self-propelled work machine according to claim 2, characterized in that a gearing is arranged between the electric motor and the central shaft.

6. The self-propelled work machine according to claim 2, in which the central shalt is part of a recuperation system for recovering electrical energy, and a storage device for the recovered electrical energy is arranged in the upper structure.

7. The self-propelled work machine according to claim 1, in which the drive unit is a combustion engine.

8. The self-propelled work machine according to claim 1, in which the drive unit includes a fuel cell.

9. The self-propelled work machine according to claim 1, in which the work machine is a crane, an excavator, a material handling machine or a telehandler.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a structure of a self-propelled work machine according to the invention in a highly schematized manner.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

(2) The drawing shows a mobile crane 10, which constitutes a self-propelled work machine. The mobile crane 10 has a two-axle undercarriage 12, which is provided with drive wheels 14, which are part of a chassis of the undercarriage 12.

(3) An upper structure 18 is mounted on the undercarriage 12 via a standard-design revolving bearing collar 16. An axis of rotation formed by the revolving bearing collar 16 is identified as A in the drawing. The revolving bearing collar 16 allows continuous rotation of the upper structure 18 on the undercarriage 12.

(4) The upper structure 18 has a driver cabin 20, in which substantially all operating elements of the mobile crane 10 are arranged, so that said operating elements can be comfortably reached by a driver of the mobile crane 10. Furthermore, a crane boom 22, which can be realized in a telescopic manner and is provided with adjusting cylinders 24 on the one hand and with a rope hoist 26 for a crane hook 28 on the other hand, is pivotably mounted on the upper structure 18.

(5) In the upper structure 18, a drive unit 30 is arranged, which is realized as a diesel engine and drives a hydraulic pump 32 for actuating the adjusting cylinders 24. Moreover, the drive unit 30 drives a power generator 34 that is connected to an electric motor 38 via electric lines 36. The electric motor 38, which is connected to a control device that can be controlled from the driver cabin 20, drives a central shaft 42 via a manual transmission 40, the axis of the central shaft 42 coinciding with the axis of rotation A of the upper structure 18. The central shaft 42 penetrates the revolving bearing collar 16 between the undercarriage 12 and the upper structure 18 and leads to a distribution gearing 44 that is arranged in the undercarriage 12 and that is connected to the drive wheels 14 of the undercarriage 12 via shafts 46.

(6) In the mobile crane described above, an electric motor that is arranged in the upper structure and is supplied by a power generator 34 thus drives the drive wheels 14 of the undercarriage 12 via the mechanical central shaft 42, which penetrates the revolving bearing collar 16. A driving motion of the mobile crane 10 is thus initiated by actuation of a drive device in the form of an electric motor 38 arranged in the upper structure 18.