WO1995013982A1

WO1995013982A1 - Cable handling device

Info

Publication number: WO1995013982A1
Application number: PCT/SE1994/001071
Authority: WO
Inventors: Göran BERGQVIST
Original assignee: Byggrobotik I Göteborg Ab
Priority date: 1993-11-16
Filing date: 1994-11-15
Publication date: 1995-05-26
Also published as: SE9303794L; SE9303794D0; AU1080595A; SE501904C2

Abstract

The invention concerns a handling device for a cable (7) extending between a point of electrical connection (11) and a driver-less, electrically operated working vehicle or a working machine (1), across a surface. Guide and control means direct the vehicle (1) along a predetermined path (13, 15, 17) on the surface (2). The vehicle is provided with a cable storage means (4) and with cable-feeding means (6), said means controlled for coordination with the operation of the vehicle (1). The feeding means are arranged, at the pace of the vehicle speed, to so pay out the cable (7) from the vehicle as the latter moves away from the electrical connection point (11) and to so pull in the cable (7) as the vehicle moves closer to the connection point (11) that the path of movement of said vehicle (1) is always left unobstructed to allow the vehicle to carry out its working operations.

Description

CABLE HANDLING DEVICE

The subject invention concerns a device for handling a cable extending between a point of electrical connec¬ tion and a vehicle.

It is common practice to use vehicles, such as driver-less, electrically operated working vehicles or self-propelled, power operated working machines to perform certain kinds of work. Such vehicles or machinery are often used today indoors, for instance in a newly-erected building wherein the vehicle or the machinery is to per¬ form operations on a newly-cast floor structure, for in¬ stance grinding or trowelling of the floor structure con- crete surface. The vehicle may comprise sophisticated con¬ trol and guidance equipment, such as laser optical direc¬ tional means, designed to measure the distance from the vehicle to the walls in the room wherein the vehicle is to operate, and it may be provided with a computer into which are stored data concerning the path or route along which the vehicle is to work as a robot.

Preferably, a vehicle of this kind is electrically operated since for environmental reasons it is unsuitable to propel the vehicle indoors with the aid of a combustion engine. In addition the steering and control of the ve¬ hicle make it necessary to supply the latter with electric current.

Under these circumstances, it has proved impractical to operate the vehicle with the aid of an electric motor that is accumulator power-supplied, because the vehicle is comparatively heavy and thus requires considerable energy in order to be able to perform its various tasks in cor¬ rect manner. For these reasons, several accumulators would have been necessary for the operation, which would have made the vehicle unnecessarily clumsy and cumbersome. Another way of supplying the vehicle with electricity would be to use a suspension means attached to the ceiling above the vehicle, which suspension device could be ar¬ ranged to successively dispense lengths of electric cable to the vehicle as the latter follows its route of opera¬ tion away from the electrical connection point and then again retract the cable when the vehicle has turned and again approaches said electrical connection point. How¬ ever, one disadvantage connected with a suspension device of this kind is the frequent changes of its installation points, for after only a brief period of installation at one working site, it is dismounted and again installed in another room or in another building. Such repeated mount¬ ing and dismantling operations complicate the work to be performed by the vehicle or the machinery when moving from one room to the next.

The invention provides a device which solves the problems outlined in the aforegoing and which is well suited to serve its purpose. The characterizing features of this device appear from the appended claims. In the performance of operations with the aid of a self-propell¬ ed, electrically operated working machine or the like as described above the device in accordance with the inven¬ tion ensures that at all times the cable assumes a posi- tion wherein it runs no risk of being damaged while at the same time it may be guided as to its position to ensure that it does not obstruct or occupy the space where the work is to be performed.

The invention will be described in closer detail in the following with reference to the accompanying drawings, wherein:

Fig. 1 is perspective view of a working machine in the shape of a robot provided with a device in accordance with the invention, and Figs. 2-4 are plan views that schematically illu¬ strate one example of a mode of operation of such a robot. As an embodiment to the describe the device in accordance with the invention has been chosen a working machine in the form of a robot 1 which is designed for surface treatment of a newly-cast concrete floor 2. The robot 1 is provided with an electrically driven propulsion device and with laser-operated guide and control equipment by means of which the position of the robot in the room may be determined successively and which is connected to a built-in computer in which are stored data representa- tive of a predetermined route across the concrete floor 2. In addition, the robot is provided with a tool 3, for in¬ stance for the purpose of trowelling the concrete floor 2. The device in accordance with the invention comprises a cable storage means 4 in the shape of a drum which is rotatably mounted on a shaft 5. Cable-fee—ng met ,s 6 are provided to wind the cable 7 on or off the drum 4. The cable 7 extends upwardly and out through the robot 1 along-side an arm 8 which is provided with runners 9 and with a runner wheel 10 at its free end and which is pivot- able into any desired angular position above the robot 1. From the runner wheel 10 the cable 7 extends downwards, towards and into contact with the floor 2, and then extends on the latter up to an electrical connection 11. The speed of rotation of the shaft 5 of the drum 4 as well as speed of the means 6 to wind the cable on or off the drum 4 and the pivotal movement of the arm 8 into the various angular positions of the latter are all determined by the control program in the computer representative of the work to be performed. The function of the device will be described in the following with reference to Figs. 2-4, showing one embodi¬ ment of the invention. When the cable 7 is inserted into the socket of the electrical connection 11 the robot 1 is able to move to a remote corner in relation to the elec- trical connection 11. In this position, the laser equip¬ ment senses the size and shape of the room the floor 2 of which is to be treated, and the computer forms a program representative of the route to be followed by the robot 1. The arm 8 is set in the angular position illustrated in Fig. 2. The robot 1 is set in motion and follows a pre¬ determined course in the direction of arrow 12. In syn- chrony with the speed of the robot 1 corresponding lengths of the cable 7 are wound off the drum 2 and out through the robot 1 and down onto the floor 2 at a pace ensuring that the cable 7 is deposited in an un-tensioned connec¬ tion, i.e. without any or with only minor mechanical load thereon, on the floor 2 laterally of the path 13 to be treated by the robot 1.

When the robot 1 reaches the opposite side of the room and turns in accordance with the program, the arm 8, also in accordance with the program, pivots to the posi- tion illustrated in Fig. 3. Thereafter, the robot 1 per¬ forms its work in the direction indicated by arrow 14. At the same time, information is supplied to the driving means of the cable drum 4 and to the feeding means 6 to pull in cable 7 into the robot 1 and wind it on to the drum 4. In this manner, the cable 7 is continuously and automatically controlled and the cable therefore does not run the risk of being damaged or assume a position wherein it constitutes an obstacle to the continuance of the work by the robot 1. When the robot 1 reaches the end of its path 15 it again turns in accordance with the program, the arm 8 pivots to the position in Fig. 4, agreeing with that in Fig. 2, and the cable drum 4 and the actuating means 6 again receive information to pay out cable 7 at the pace of movement of the robot 1 in the direction of arrow 16, whereby a new path 17 is treated while corresponding lengths of cable 7 are successively deposited laterally outside the latter.

The invention is not limited to the embodiment illu- strated and described in the foregoing but could be varied in various ways within the scope of the appended claims. For instance, the cable drum 4 may be eliminated and the cable 17 simply be deposited in a loop at the bottom of the robot 1, the feeding means 6 ensuring that the cable 17 is pulled in and positioned in even winding turns.

In accordance with a somewhat simplified embodiment of the device in accordance with the invention the arm 8 may be freely pivotable when the pattern of movement of the robot 1 is such that already a minor pulling-in of the cable 7 causes the arm to be automatically set in such a position that the path of movement of the robot 1 is un- obstructed.

The device in accordance with the invention may be used in many different applications in working vehicles or machinery designed for many various types of work and wherein the machinery or the robot are controlled by various means.

Claims

1. A handling device for a cable (7) extending be- tween a point of electrical connection (11) and a vehicle (1), such as a driver-less, electrically operated working vehicle or a self-propelled power-operated working machine, which vehicle is arranged to successively move across a surface (2), e.g. for treatment thereof, and provided with guide and control means to direct the ve¬ hicle (1) along a predetermined path (13, 15, 17) on the surface (2), c h a r a c t e r i z e d in that the ve¬ hicle (1) likewise is provided with a cable storage means (4) and with cable-feeding means (6), said means con- trolled for coordination with the operation of the vehicle (1) and arranged, at the pace of the vehicle speed, to so pay out the cable (7) from the vehicle as the latter moves away from the electrical connection point (11) and to so pull in the cable (7) as the vehicle moves closer to the connection point (11) that the path of movement of said vehicle (1) is always left unobstructed to allow the ve¬ hicle to carry out its working operations.

2. A device as claimed in claim 1, c h a r a c ¬ t e r i z e d in that the vehicle (1) is provided with an arm (8) along which said cable (7) runs, said arm (8) extending above and beyond said vehicle and arranged to perform controlled pivotal movements relatively to the ve¬ hicle (1) so as to assume predetermined angular positions calculated in dependency of the pre-programmed path of movement (13, 15, 17) of the vehicle (1), for the purpose of keeping the cable (7) out of the way at all times, thus ensuring that the vehicle path of movement is left unob¬ structed.