RELATED APPLICATIONS

This application is a national phase of International Patent Application No. PCT/EP2016/000322 filed Feb. 25, 2016, which claims the filing benefit of German Patent Application No. 10 2015 003 736.6 filed Mar. 21, 2015, the contents of both of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a trolley for the transportation of workpieces, said trolley being movable in a transport direction on a carrier rail, comprisinga) a trolley chassis, which supports at least one drive roller that is rollable on a drive running surface of the carrier rail and is drivable by means of a drive motor, which latter is carried along by the trolley chassis;b) at least one fastening device for at least one workpiece.

In addition, the invention relates to a plant for the transportation of objects, comprisinga) a rail system, which comprises at least one carrier rail;b) at least one trolley movable in a transport direction on the carrier rail.

BACKGROUND OF THE INVENTION

In plants of this type, the trolleys must be supplied with power, for which purpose, in the case of commercially known plants, busbars are laid along the carrier rail, from which busbars a trolley can obtain power via appropriately adapted current collectors. This can be done via contact lines or contactlessly.

However, a power supply of this type is structurally very complex, maintenance-intensive and fragile. Moreover, stoppages frequently arise when there are problems with the power supply, since generally the rail system too is then affected.

SUMMARY OF THE INVENTION

An object of the invention is therefore to provide a trolley and plant of the type stated in the introduction, which enable an efficient, maintenance-friendly and reliable operation.

This object may be achieved in a trolley of the type stated in the introduction by virtue of the fact thatc) the trolley carries along with it an autonomous power supply device, by means of which the drive motor can be supplied with power.

In this way, an installation for supplying power along the carrier rail can be dispensed with. A failure of the power supply of a trolley is then always confined to the trolley itself, so that a defective trolley of this kind can be exchanged without the rail system needing to be worked on.

It is here particularly favorable if the autonomous power supply device comprises at least one rechargeable energy store. For this, accumulators or capacitors, in particular, can be considered.

If the trolley chassis comprises a leading unit, which runs ahead in the transport direction, and a trailing unit, which runs behind in the transport direction, said units being coupled with the fastening device, the system can be of curved configuration when the coupling points are formed by appropriate rotary couplings.

With regard to the drive, it is here advantageous ifa) the leading unit bears a drive roller and a drive motor;and/orb) the trailing unit bears a drive roller and a drive motor;whereinc) the leading unit and/or the trailing unit bear(s) at least one rechargeable energy store.

Thus only the leading unit or only the trailing unit, or each of the two units can be driven. In this case, the driven unit does not always have also to bear an energy store.

As an effective drive concept, it can be provided that the trolley is configured as a transport train, in which the trolley chassis comprises a drive unit and one or more passive transport units, which are releasably coupled with one another, wherein at least the transport units respectively comprise a fastening device. In this way, savings can be made on drive components.

It can here be favorable if the trolley chassis comprises as the drive unit a drivable transport unit, having a chassis which carries the at least one drive roller along with it, and a fastening device for at least one workpiece. In this case, the drive unit is used for the transport of workpieces.

Alternatively, it can be favorable if the trolley chassis comprises as the drive unit a towing trolley without carrying function and having a chassis unit which carries along with it the at least one drive roller. In this case, a type of loco principle is realized.

In both concepts, it is of advantage if the drive unit carries along with it the autonomous power supply unit. No lengthy connections of the power source to the drive motor, or power couplings between individual chassis regions, are then necessary.

The above-described object is achieved in a plant of the type stated in the introduction by virtue of the fact that the trolley is a trolley having some or all of the above-described features.

This conveying and power supply concept can be implemented particularly effectively if the carrier rail is fixed to the ground.

It is to be understood that the aspects and objects of the present invention described above may be combinable and that other advantages and aspects of the present invention will become apparent upon reading the following description of the drawings and detailed description of the invention.

