SE543845C2

SE543845C2 - A floor surfacing machine with different drive motors

Info

Publication number: SE543845C2
Application number: SE1951402A
Authority: SE
Inventors: Peter Lundgren; Ulf Petersson
Original assignee: Husqvarna Ab
Priority date: 2019-12-05
Filing date: 2019-12-05
Publication date: 2021-08-10
Also published as: EP4069464A1; US20230011888A1; AU2020396043A1; WO2021112738A1; CN114761176A; EP4069464A4; SE1951402A1

Abstract

The present disclosure relates to a floor surfacing machine (100) comprising drive wheels (171, 172) and a planetary head (140) with one or more satellite grinding heads (120), A first drive motor (110) is arranged to drive the planetary head (140) and a second drive motor (130, 430) is arranged to drive the one or more satellite grinding heads (120). The first drive motor (110) is arranged to be directly powered only by means of a re-chargeable internal electrical power source (310) comprised in the floor surfacing machine (100).

Description

TECHNICAL FIELD There is disclosed herein a floor surtacing machine comprising a planetary head withone or more satellite grinding heads. A first drive motor is arranged to drive theplanetary head and a second drive motor is arranged to drive the one or more satellitegrinding heads.

BACKGROUND A tioor surtaoiiwg or grinding machine is cornmoniy used to strip or smooth tiooringsurtaces hy grinding away undesired rnateriai. Fioor siirtacing rnachines provide ciean,smooth and essentiaiiy tiat stirtaces to tyhich new coverings or coatings can he appiied.Fioor surtacing rnachines are aiso commoniy used to smooth rough tiooring siiriacesor to remove surface ieveiiing compounds to create a tioor which has a smooth andievei surface. Certain sertaces, inciuding some types ot concrete, are aiso suitahie torpoiishing using a tioor surtacing machine.

Gne common type ot a 'iioor stiriacing machine is the pianetary~type machine. Thistype ot machine normaiiy comprises two to tour, or even more, sateiiite grinding headsinounted to a iarger pianetary head, where the sateiiite grinding heads may he drivenin one direction and the pianetary head in another direction. A motor, norrnaiiy aneieotricai motor, drives hoth the sateiiite grinding heads and the pianetary head, wheretransmission is accompiished hy means ot transmission heits and hett puiieys. Themotor is either a cornhustion engine or powered trom the eiectricai mains ot a powernetwork.

Some tioor grinding machines comprise a tirst inotor arranged to drive the hianetaryhead, and a second motor arranged to drive the sateiiite grinding heads. US 6,54t),596 Bi discioses a surtacing machine with two drive inotors.

A tioor stirtacing machine normaiiy requires high power to operate. When powered hycahie trom eiectricai mains, a 32 Ampere (A) source or higher may he required.

However, many construction sites oniy provide "iß A sources, vvhich is not enough tor pewering fieer surfacing rnaehines reduiring mere pewer. thus, starting te use a tieersurfacing rnaehine ean be deiayed, made rnere difticuit, er in the worst case madeirnpeesibie, in these cases in whieh the eiectricity distribution grid at the ieeatien cannot suppiy the current that the fieer surfacing rnaehine requires. it may net even be pessipie ter the fieer surfacing rnaehine te be driven ett ef thetranspert vehieie with which it has been transperted to the reievant werit ieeatien, duete the tack ef a required external power source such as electrical mains available. it isef eeurse pessibie te have a pertabie eewer suppiy system, but such a seiutien is naturaiiy expensive and curnbersente te handie.

There is thus a need fer fieer surfacing rnaehines which are abie te eperate aise at sueh censtructien/werk sites.

SUMMARYlt is an object of the present disclosure to provide a floor surfacing machine that is abie te eperate at construction/work sites where sutiieient eiectricai power ie unavaiiapie.

This object is accomplished by means of a floor surfacing machine that comprises drivewheels and a planetary head with one or more satellite grinding heads, where a firstdrive motor is arranged to drive the planetary head and where a second drive motor isarranged to drive the one or more satellite grinding heads. The first drive motor isarranged to be directly powered only by means of a re-chargeable onboard electrical power source comprised in the floor surfacing machine.

This means that the first drive motor that is arranged to drive the planetary head canbe powered separately, such that the eiectricai power avaiiabie can be used te pewerthe second drive motor that is arranged to drive said satellite grinding heads.

According to some aspects, the internal onboard power source is adapted to becharged by a battery charger that in turn is adapted to be powered by an external electrical power source. ln this manner, the onboard electrical power source can be easily recharged when necessary.

According to some aspects, the floor surfacing machine comprises an onboard batterycharger that is adapted to charge the onboard electrical power source.

This means that a battery charger always is available.

According to some aspects, the second drive motor is an internal combustion engine.

This means that the floor surfacing machine can be used where there is no external power source such as electrical mains available.

According to some aspects, the internal combustion engine is fueled by propane.This provides an environment-friendly internal combustion engine.

According to some aspects, the second drive motor comprises an electrical generatorthat is adapted to power a battery charger that is adapted to charge the onboard electrical power source.

This means that the onboard electrical power source can be charged without access to an external power source such as electrical mains.

According to some aspects, the floor surfacing machine comprises an internallyarranged battery charger that is adapted to charge the onboard electrical power sourceand is connected to the electrical generator.

This means that a battery charger always is available.

According to some aspects, the second drive motor is arranged to be directly poweredby an electrical mains connection.

According to some aspects, the second drive motor is arranged to be directly powered only by means of the re-chargeable onboard electrical power source.

This means that both drive motors have a stable power supply and, in addition to this,also can be operated without connection to the electrical mains as long as the chargeable onboard electrical power source is sufficiently charged.

According to some aspects, the onboard electrical power source is adapted to providea battery current that is divided into a first current to the first drive motor and a secondcurrent to the second drive motor. ln a certain operational state, the first drive motor isadapted to act as a generator and generate a third current that adds to the second current.

This means that energy that is created by means of the operation of the ﬂoor surfacingmachine is re-used, increasing the running time between having to charge the onboard electrical power source.

According to some aspects, the floor surfacing machine comprises a drivearrangement configured to propel the drive wheels. The drive arrangement comprisesat least one electric motor that is adapted to be powered by means of a re-chargeable onboard electrical power source.This means that the fioer surfacing machine easily can be driven off of the transportvehicle with which it has been transported to the relevant work lecatien, even without access to an external power source such as electrical mains.

According to some aspects, the same onboard electrical power source is adapted topower the first drive motor and the drive arrangement.

This means that only one onboard electrical power source is needed.

According to some aspects, a separate onboard electrical power source is adapted toonly power the drive arrangement.

This means that the drive arrangement can be powered by means of an onboard electrical power source that is adapted for the requirements of the drive arrangement.

According to some aspects, the drive arrangement comprises a sensing arrangementthat is adapted to switch between having the drive arrangement powered by theonboard electrical power source or by the electrical maine dependent en the powerpresently available from the onboard electrical power source and the electrical maine. ln this way, the onboard electrical power source is used for powering the drive arrangement only when electrical inaina le nat available.

According to some aspects, the onboard electrical power source is positioned abovethe wheels such that the weight of the onboard electrical power source provides apressure of the wheels towards a floor. The pressure is adapted to increase traction ofthe floor surfacing machine.

According to some aspects, the onboard electrical power source is positioned suchthat, during operation of the floor surfacing machine, an extension along a closestdistance between a mass center of the onboard electrical power source and the floorpasses between the drive wheels.

This provides a pressure of the wheels towards a floor, where the pressure is adaptedto increase traction of the floor surfacing machine.

According to some aspects, the re-chargeable onboard electrical power source isconstituted by a battery.

According to some aspects, the internal onboard power source is adapted to becharged by a battery charger that in turn is adapted to be powered by an externalelectrical power source that is constituted by a 12 VDC or 24 VDC supply.

Such an external electrical power source can be available in a transport vehicle whichmeans that the battery charger can be charged during transport to and from work sites.

Generally, all terms used in the claims are to be interpreted according to their ordinarymeaning in the technical field, unless explicitly defined otherwise herein. All referencesto "a/an/the element, apparatus, component, means, step, etc." are to be interpretedopenly as referring to at least one instance of the element, apparatus, component,means, step, etc., unless explicitly stated otherwise. The steps of any methoddisclosed herein do not have to be performed in the exact order disclosed, unlessexplicitly stated. Further features of, and advantages with, the present invention willbecome apparent when studying the appended claims and the following description.The skilled person realizes that different features of the present invention may becombined to create embodiments other than those described in the following, withoutdeparting from the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGSThe present disclosure will now be described more in detail with reference to theappended drawings, where: Figures 1A-D illustrate views of an example floor surfacing machine.

Figures 2A-B show an example planetary head with satellite grinding heads; Figure 3 schematically illustrates how the drive motors are powered accordingto a first example; Figure 4A schematically illustrates how the drive motors are powered accordingto a second example; Figure 4B schematically illustrates a further aspect of the second example; Figure 5A-B schematically illustrate a lower part of the floor surfacing machine; Figure 6A-B schematically illustrate examples of drive arrangements Figure 7 schematically illustrates how the drive motors are powered according to a third example; Figure 8 schematically illustrates rotation directions of the planetary head andthe satellite grinding heads; andFigure 9 schematically illustrates an example of a first drive motor.

DETAILED DESCRIPTION The invention will now be described more fully hereinafter with reference to theaccompanying drawings, in which certain aspects of the invention are shown. Thisinvention may, however, be embodied in many different forms and should not beconstrued as limited to the embodiments and aspects set forth herein; rather, theseembodiments are provided by way of example so that this disclosure will be thoroughand complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout the description.

Figures1A-1Dillustrate views of a floor surfacing machine 100, such as a floor grindingmachine, comprising two drive motors 110, 130. A first drive motor 110 is arranged todrive a planetary head 140. A second drive motor 130 is arranged to drive a pluralityof satellite grinding heads 120. A cover 107 protects the planetary head 140 and thesatellite grinding heads 120 and allows for dust and debris to be sucked up via an outlet opening 160.

A forward direction F of the floor surfacing machine 100 is defined as extending awayfrom the handle part 105 which comprises the user controls 109 for operating themachine. The forward direction F can also be said to be extending away from wheels171, 172 of the floor surfacing machine 100. A lateral direction extends orthogonal tothe forward direction, i.e., orthogonal to an extension plane P of the wheels 171, 172, shown in Figure 1B.

The left 171 and right 172 wheels of the floor surfacing machine 100 are attached viarespective wheel support assemblies 106. According to some aspects, the floorsurfacing machine 100 also comprises a support wheel 173 arranged in front of thewheels 171, 172 and being intended to be used during transport of the floor surfacing machine 100.. According to some aspects, each wheel support assembly 106 also comprises an integrated drive arrangement 190 configured to propel the wheels 171,172 which then are constituted by drive wheels 171, 172. The drive arrangement 190may, e.g., be based on electric motors connected to respective drive wheels 171, 172,or a common electric motor that is adapted to propel the drive wheels 171, 172.According to some further aspects, alternatively, there is no integrated drivearrangement 190 configured to propel any drive wheels, only wheels 171, 172 that areadapted for manual maneuvering of the floor surfacing machine 100.

The drive arrangement 190 may be arranged in any other suitable manner, and theremay be only one drive arrangement 190 adapted to propel both wheels 171, 172.Generally, according to some aspects, the floor surfacing machine 100 comprises drivewheels 171, 172 and a drive arrangement 190 configured to propel the drive wheels171, 172, where the drive arrangement 190 according to some aspects comprises atleast one electric motor, and preferably two electric motors one for driving the left drivewheel 171 and the other for driving the right drive wheel 172.

The floor surfacing machine 100 may be operated by controls on the machine, and/or remotely via remote control.

Figures 2A and 2B illustrate details of the drive arrangement for driving the satellitegrinding heads 120. Each satellite grinding head 120 is fixedly attached to a belt pulley210, which is driven by a belt 220 from a central pulley 260 driven by a motor axle 135of the second drive motor 130. The floor surfacing machine 100 normally comprisesthree satellite grinding heads 120, but any suitable number of grinding heads can beprovided, typically two -five satellite grinding heads.

The planetary head 140 is rotated about the motor axle 135 of the second drive motor130 by the first drive motor 110. The direction of rotation R1 of the planetary head 140and the direction of rotation R2 of the satellite grinding heads are controlledindependently from each other, which is an advantage.

Floor surfacing machines such as the floor surfacing machine 100 with independentlyoperable first and second drive motors were described in US 6540596 Bi, and alsoin SE 539 542 C2, and will therefore not be discussed in more detail herein.

With reference to Figure 3, schematically illustrating a first example according to thepresent disclosure, the first drive motor 110 is connected to an internal power sourcesuch as a battery 310 that can be an onboard battery, which battery 310 according tosome aspects is connectable to an external, or internally arranged, battery charger330. According to some aspects, an internally arranged battery charger is an onboardcharger that under normal operating conditions is adapted to travel with the floorsurfacing machine 100 together with an onboard battery 310. ln this context, a batterycharger is a conventional battery charger of any suitable type that provides a certainvoltage and charging current for the battery 310. The battery charger can be providedby well-known protection circuitry that for example avoid over-charging and over- heating, as well as internal leakage and short-circuit.

According to some further aspects, the second drive motor 130 is adapted to beconnected to an external power supply such as electrical matris 320 ef a powernetwork. This means that when the floor surfacing machine 100 is in operation, onlythe second drive motor 130 is using power from the electrical maihe 320, and erlly thepower requlremeht of the second drive motor 130 limits where the floor surfacingmachine 100 can be operated. By adapting the second drive motor 130 to require nomore than 16 Amperes, the floor surfacing machine 100 can be operated at most worksites without problem. The remainder of the floor surfacing machine's power requirement may be provided by means of the battery 310.

According to some aspects, in the case of an internally arranged battery charger 330,the battery charger 330 can be activated when the second drive motor 130 isconnected to the electrical mains 320, either automatically er by means ef a setting ihferred by a user. lf adrriitted by the available power supply of the electrical maihs 320 and the presentpower consumption ef the first drive motor 110, the battery 310 cah be chargecl duringeperatien of the floor surfacing machine 100. Otherwise, the battery charger 330 isonly activated when the floor surfacing machine 100 is not running or partially running, for example if only the first drive motor 110 is not running.

According to some aspects, with reference to Figure 4A that schematically illustratesa second example, the second drive motor 430 is a combustion engine, for example apropane engine. This means that eiectricai maine 320 eniy are needed when thebattery 310 ie to be charged. Aiternativeiy, or ae a euppiernent, as indicated tivithdashed iines, the second drive motor 430 comprises a generator 440 that isconnectable to the battery charger 330 for charging the battery 310 when the seconddrive motor 430 is running. ln this case, according to some further aspects, thegenerator 440 can be disengaged if all available power generated by the second drivemotor 430 has to be used for a grinding procedure. The battery charger 330 can beeither external or internally arranged, examples of this will be discussed more in detailbelow.

Figure 4B corresponds to Figure 4A and schematically illustrates further aspects of thepresent disclosure, where both an internal battery charger 33A and an external batterycharger 330B are indicated with dashed lines as being possible optional and/oralternatives, even in combination. Regarding having an internal battery charger and/oran external battery charger, it is conceivable that the battery 310 can be charged byan internal battery charger 330A that is comprised in the floor surfacing machine 100,as well as by an external battery charger 330B. An internal battery charger 330A canaccording to some aspects be inaccessible within the floor surfacing machine 100 andonly be used for charging by means of the generator 440, and an external batterycharger 330B can be used for charging via the eiectricai maine 320. Aiternativeiy or asa cernpiement, the different battery chargere 330A, 330B can have different charging efficiency depending en the intended avaiiabie input pewa-r.

Severai type-e ef externai battery chargere can be avaiiabie ter an eperater dependingen the avaiiabie charging power. Fer exampie, a three-phase battery charger cannerrnaiiy provide a mere efficient charging than a dne«phaee battery charger.

The battery 310 can thus be adapted td be charged by an internai battery charger 330Aeniy, and an externai battery charger 330B eniy, er by bath an internai battery charger330A and an externai battery charger 330B. in the caee cf the battery 310 beingadapted te be charged by an internai battery charger 330A eniy, the internai batterycharger 330A ehduid euitabiy be adapted te be cdnnectabie te the eiectricai rnaine 320. 11 ln this context, when an internal battery charger 330A is mentioned to be inaccessiblewithin the floor surfacing machine 100, this does according to some aspects mean thatthe internal battery charger 330A at least does not have any connections that areaccessible or available for an operator.

According to some aspects, as a possibility that is applicable for all examples, whenthe drive arrangement 190 is constituted by electric wheel motors connected to therespective drive wheel 171, 172, the electric wheel motors 190 are powered by thebattery 310. Alternatively, an operator can choose whether the electric wheel motors190 are powered by the battery 310 or by the electrical maine 320. According to someaspects, the drive arrangement 190 comprises a sensing arrangement 502 that isadapted to switch between having the electric wheel motors 190 powered by thebattery 310 or by the electrical maine 320 depenclerlt en the pott/er presently availablefrem the battery 310 and the electrical mains 320 in view ef present operating endcharging conclitlens. Having the opportunity to have the electric wheel motors 190powered by the battery 310 enables an operator to easily move and load/unload thefloor surfacing machine 100 even if an electrical mains supply is unavailable or hard toreach. Loading/unloading of a floor surfacing machine 100 may involve transportingthe floor surfacing machine 100 upwards or downwards a loading ramp or similar,where operating wheel motors are desirable. According to some aspects, the wheels171, 172 can be driven by a single common wheel motor that can be powered asdescribed above. The above is of course also applicable for the case of a commonelectric wheel motor connected to the drive wheels 171 , 172.

Furthermore, as schematically indicated in Figure 1A, Figure 1C, Figure 5A and Figure5B and according to some further aspects, the battery 310 is positioned above thewheels 171, 172, overlapping the wheels 171, 172 seen from above, such that theweight of the battery 310 provides an enhanced pressure of the wheels 171, 172towards the floor 500. Preferably, the battery 310 is mounted on the machine in aposition so as to overlap the common axis of rotation of the two drive wheels 171, 172along a direction being perpendicular to a plane defined by the lowest portions of thedriving wheels 171, 172 and the satellite grinding heads 120. 12 By using the weight of the battery 310, the drive wheels 171, 172 of the floor surfacingmachine 100 are weighted down to provide traction, where the weight comprised in thebattery 310 is well positioned to provide traction.

According to some aspects, with particular reference to Figure 5A and Figure 5B, thebattery 310 is positioned such that, during operation of the floor surfacing machine100, an extension along a closest distance D between a mass center 501 of the battery310 and the floor 500 passes between the wheels 171, 172.

According to some aspects, the battery 310 is positioned such that, during operationof the floor surfacing machine 100, an extension along a closest distance D betweena part of the battery 310 and the floor 500 passes between the wheels 171, 172.

According to some aspects, as an example the first motor 110 is rated 1,5 kW, and thebattery 310 is rated 9kWh, which means that a fully charged battery lasts for about sixhours that normally is fully satisfactory. ln the case of the second motor being a combustion engine 430 with a generator 440that is adapted to charge the battery 310 via a battery charger during operation, thebattery will last even longer.

The present disclosure is not limited to the examples above, but may vary freely withinthe scope of the appended claims. For example, the user controls 109 can comprise abattery charge indicator, where the battery's remaining power is indicated, as well asthe progress of a running charging procedure. According to some aspects, the usercontrols 109 comprise a battery condition indicator that is adapted to indicate differentbattery conditions such as for example overheated, unable to charge, low capacity,internally damaged etc. Such a battery condition indicator can be integrated with thebattery charge indicator.

According to some aspects, the user controls 109 comprise control means forcontrolling charging the battery 310 or not in the case of the floor surfacing machine100 comprising a generator 440 that is adapted to power a battery charger 330, 330A. 13 lt is conceivable that the second drive motor 430 is used for running the generator 440even when the floor surfacing machine 100 is stationary in order to charge the battery310. The battery 310 the floor surfacing machine 100 comprising a generator 440 canof course also be charged by a battery charger 330, 330A, 330B powered by theelectrical mains 320 when the floor surfacing machine 100 is stationary.

Other types of internal power sources than a battery is conceivable, for example a fuelcell. Generally, the first motor 110 is adapted to be directly powered only by means ofa re-chargeable onboard electrical power source 310 comprised in the floor surfacingmachine, where, according to some aspects, the re-chargeable electrical power source310 is internally arranged in the floor surfacing machine 100, being onboard the floorsurfacing machine 100, and suitably integrated with the floor surfacing machine 100.ln the case of a fuel cell or similar, the charging is accomplished by providing a suitable fuel. ln the case of a battery being used, the battery is to be regarded as a batteryarrangement that can comprise one or more separate batteries, where each batterycan comprise any number of battery cells or the like, and being of any suitable typesuch as Li-ion.

According to some aspects, the battery 310 is easily removable for an operator, eitherin the case of malfunction, or when an operator has one or more spare batteries forthe case of a present battery being depleted of power before the operator intends tofinish working for the day.

A general concept of the present disclosure is that the first drive motor 110 that isarranged to drive the planetary head 140 is arranged to be directly powered only bymeans of a re-chargeable internal electrical power source 310 comprised in, and beingpositioned onboard the floor surfacing machine 100, suitably integrated with the floorsurfacing machine 100, while the second drive motor 130, 430 that is arranged to drivethe one or more satellite grinding heads 120 is arranged to be powered by means ofanother power source such as the electrical mains or being in the form ofa combustionengine that here has been exemplified by a propane fueled combustion engine. 14 According to some aspects, a petrol fueled combustion engine is conceivable as well. for the second drive motor 430.

According to some aspects, as illustrated with a dashed connection line 340 in Figure3, the battery 310 can be used as an auxiliary power source for the second drive motor130. This can be advantageous in cases of an inadequate or malfunctioning externalelectrical network 320 that, at least during some times, is not able to provide sufficientpower to the second drive motor 130. Another example where the battery 310 is usedfor powering both drive motors 110, 130 will be discussed later with reference to Figure7.

According to some aspects, instead of the belt drive arrangement for driving thesatellite grinding heads that is illustrated in Figures 2A and 2B, a geared transmission can be used.

Regarding the planetary head, Figure 6A shows an example drive arrangement 600for driving the planetary head 140 of the floor surfacing machine 100. The drivearrangement 600 comprises a first drive wheel 610 arranged to be driven by the firstdrive motor 110. A second drive wheel 630 is fixedly attached to the planetary head140 and arranged to be driven by the first drive wheel 610 via a connecting member620, such as a chain or a belt. ln case a drive chain is used, the first drive wheel 310and the second 330 drive wheel are sprockets configured to engage the drive chain tobring the planetary head 140 into rotation.

According to some aspects, the drive chain is a self-lubricating chain. This furtherreduces the maintenance need of the drive arrangement, since the self-lubricatingdrive chain can be designed to last the entire excepted lifetime of the floor surfacingmachine 100. ln case a normal chain is used, a protective casing 640 can be designed to hold an amount of lubricating agent, e.g., lubricating oil. ln case a drive belt is used, the first 310 and second 330 drive wheels are belt pulleysconfigured to engage the drive belt to bring the planetary head 140 into rotation.

Figure 6B shows a schematic top view of another drive arrangement 600”. Here theconnecting member is a geared connection, i.e., a gear train comprising one or moregears 650, 660. The geared connection may be part of a gear transmissionarrangement. The geared connecting member also provides a power ratio. ln otherwords, according to some aspects, the connecting member 620 comprises a gear train650, 660 arranged to transfer power from the first motor 110 to the second drive wheel630. The gear train may be part of a gear transmission system, i.e., can be configuredwith a given gear ratio. ln case the protective casing 640 is arranged to hold an amountof Iubricating agent, e.g., Iubricating oil, the geared connection may be lubricated bythe agent, thus providing extended service interval, since the Iubricating agent is protected from outside contamination.

The internally arranged battery charger 330A is generally constituted by an onboardbattery charger 330A that can be easily accessible or more or less integrated in the floor surfacing machine 100.

Figure 7 shows a third example of the present disclosure. Here, there is a batterycharger 730 that is connected to the electrical mains 720. The battery charger 730 isin turn connected to a first battery 710A, and is adapted to charge the first battery710A. According to some aspects, the battery charger 730 comprises a selectiondevice that automatically or manually is adapted to select a power input source, suchas for example 400V three-phase AC or 240V one-phase AC.

The first battery 710A is adapted to power both the first drive motor 1 10 and the seconddrive motor 130, such that the drive motors 110, 130 are directly powered only bymeans of the first battery 710A which in turn is charged by the battery charger 730.This means that both drive motors 110, 130 have a stable power supply and, in additionto this, also can be operated without connection to the electrical mains 720 as long asthe first battery 710 is sufficiently charged.

During running in a first operational state, the battery 710A provides a battery currenti that is divided into a first current i1 to the first drive motor 110 and a second current i2 to the second drive motor 130. However, according to some aspects, the operational 16 state can in some running conditions be changed to a second operational state. Asshown in Figure 8, the planetary head 140 has a planetary direction of rotation R, andthe satellite grinding heads 120 have a respective satellite direction of rotation ri, r2, rswhich are opposite the planetary direction of rotation R. During the second operationalstate, when the second drive motor 130 runs the satellite grinding heads 120, therotation power induced, and the friction of the grinded floor, causes the planetary head140 to rotate in the planetary direction of rotation R. This means that instead ofdrawingthe first current i1, the first drive motor 110 acts as a generator and generates a thirdcurrent is that adds to the second current i2 as lllustrated in Figure 7.

With reference to Figure 1C, Figure 1D, Figure 5A, Figure 5D and Figure 7, accordingto some aspects the floor surfacing machine 100 of the third example comprises drivewheels 171, 172 and a drive arrangement 190 configured to propel the drive wheels171, 172, where the drive arrangement 190 comprises at least one electric motor. ln the following, two alternatives are presented.

The first alternative is indicated with dash-dotted lines in Figure 7. Here, a separatesecond battery 71 OB is adapted to power the drive arrangement 190 in order to enablethe drive arrangement 190 to propel the drive wheels 171, 172. The second battery710B is adapted to be charged by the same battery charger 730 as the first battery710A, but an alternative charger is of course conceivable.

The second alternative is indicated with dashed lines in Figure 7. Here, the first battery710A is adapted to power the drive arrangement 190 in order to enable the drivearrangement 190 to propel the rive wheels 171, 172. The same battery 710A is thusadapted for powering the first drive motor 110, the second drive motor 130 and the drive arrangement 190.

A combination between the first example and the second example is of course conceivable.

According to some aspects, the battery charger 730 is either an external batterycharger, or an onboard battery charger. The battery charger 730 can also in practice 17 comprise two or more separate battery sub-chargers, where one or more battery sub- chargers are external and one or more battery sub-chargers are positioned onboard.

Figure 9 shows an example of the first drive motor 110 that comprises a DC/ACconverter 901 that is adapted to convert a DC battery supply 903 to AC that is used inan electric motor 902 that according to some aspects can be a synchronous motor ora permanent magnet motor. ln the case of the second drive motor 130 also beingbattery-driven as for example described above with reference to Figure 7, thearrangement of Figure 9 is applicable for the second drive motor 130 as well.

The electric motor 902 is according to some aspects a three-phase electric motor asindicated in Figure 9, which means that the present disclosure enables running a three-phase electric motor 902 from a one-phase electrical mains 720.

According to some aspects, for all examples and illustrated for the third example inFigure 7, the battery charger 730 is adapted to be connected to a low-voltage powersource, such as a 12 VDC or 24 VDC supply 750 that can be available in a transportvehicle. This means that the battery charger 730 can be charged during transport toand from work sites. Generally, the electrical mains 320, 720 and the 12 VDC or 24VDC supply 750 all constitute an external electrical power source. The electrical mains320, 720 is connected to an external power network, and the 12 VDC or 24 VDC supply750 can either be supplied by an electrical main or by means of a vehiclebattery/generator. ln all cases, the first drive motor 110 is arranged to be directly powered only by meansof a re-chargeable onboard electrical power source 310 comprised in the floorsurfacing machine 100. For the examples according to the third example illustrated inFigure 7, the first drive motor 110 can be indirectly powered by the electrical mains 720or the 12/24 VDC supply 750. Any of these is adapted to power the battery charger730, where the battery charger 730 is adapted to charge the battery 710A. The battery710A, that generally is constituted by a re-chargeable onboard electrical power source,is in turn arranged to directly power the first drive motor 110. 18 An internally arranged battery charger can according to some aspects be regarded as an onboard battery charger.

Generally, the present disclosure re|ates to a floor surfacing machine 100, 400, 700comprising drive wheels 171, 172 and a planetary head 140 with one or more satellitegrinding heads 120, where a first drive motor 110 is arranged to drive the planetaryhead 140 and where a second drive motor 130, 430 is arranged to drive the one ormore satellite grinding heads 120, wherein the first drive motor 110 is arranged to bedirectly powered only by means of a re-chargeable onboard electrical power source310, 710A comprised in the floor surfacing machine 100, 400, 700.

According to some aspects, the internal onboard power source 310, 710A is adaptedto be charged by a battery charger 330; 330A, 330B, 730 that in turn is adapted to be powered by an external electrical power source 320, 720, 750.

According to some aspects, the floor surfacing machine 100, 400, 700 comprises anonboard battery charger 330A, 730 that is adapted to charge the onboard electricalpower source 310, 710A.

According to some aspects, the second drive motor 430 is an internal combustion engine.

According to some aspects, the internal combustion engine is fueled by propane.

According to some aspects, the second drive motor 430 comprises an electricalgenerator 440 that is adapted to power a battery charger 330, 330A that is adapted to charge the onboard electrical power source 310.

According to some aspects, the floor surfacing machine 400 comprises an internallyarranged battery charger 330A that is adapted to charge the onboard electrical power source 310 and is connected to the electrical generator 440.

According to some aspects, the second drive motor 130 is arranged to be directlypowered by an electrical mains connection 320. 19 According to some aspects, the second drive motor 130 is arranged to be directlypowered only by means of the re-chargeable onboard electrical power source 71 OA.

According to some aspects, the onboard electrical power source 710A is adapted toprovide a battery current i that is divided into a first current i1 to the first drive motor110 and a second current i2 to the second drive motor 130 where, in a certainoperational state, the first drive motor 110 is adapted to act as a generator and generate a third current is that adds to the second current i2.

According to some aspects, the floor surfacing machine 100 comprises a drivearrangement 190 configured to propel the drive wheels 171, 172, where the drivearrangement 190 comprises at least one electric motor that is adapted to be powered by means of a re-chargeable onboard electrical power source 310, 710A; 710B.

According to some aspects, the same onboard electrical power source 310, 710A isadapted to power the first drive motor 110 and the drive arrangement 190.

According to some aspects, a separate onboard electrical power source 710B is adapted to only power the drive arrangement 190.

According to some aspects, the drive arrangement 190 comprises a sensingarrangement 502 that is adapted to switch between having the drive arrangement 190powered by the onboard electrical power source 310, 710A, 710B or by the electricalmaine 320, 720 dependent on the power presentiy available from the onboard electricalpower source 310, 710A, 710B and the electrical maine 320, YZO.

According to some aspects, the onboard electrical power source 310 is positionedabove the wheels 171, 172 such that the weight of the onboard electrical power source310 provides a pressure of the wheels 171, 172 towards a floor 500, where said pressure is adapted to increase traction of the floor surfacing machine 100.

According to some aspects, the onboard electrical power source 310 is positioned suchthat, during operation of the floor surfacing machine 100, an extension along a closest distance D between a mass center 501 of the onboard electrical power source 310 andthe floor 500 passes between the drive wheels 171, 172.

According to some aspects, the re-chargeable onboard electrical power source 310 isconstituted by a battery 310.

According to some aspects, the internal onboard power source 710A is adapted to becharged by a battery charger 730 that in turn is adapted to be powered by an externalelectrical power source 750 that is constituted by a 12 VDC or 24 VDC supply 750.

Claims

CLA||\/IS

1. A floor surfacing machine (100, 400, 700) comprising drive wheels (171,172) and a planetary head (140) with one or more satellite grinding heads (120), wherea first drive motor (110) is arranged to drive the planetary head (140) and where asecond drive motor (130, 430) is arranged to drive the one or more satellite grindingheads (120), wherein the first drive motor (110) is arranged to be direetiy-powered eaiyby means of a re-chargeabie onboard electrical power source (310, 710A) comprisedin the floor surfacing machine (100, 400, 700), vvherešn the second drive :notor (130) is arranged to be povifered by en eiectiicai iiiains connection (320) _

2. The floor surfacing machine (100, 400, 700) according to claim 1, whereinthe onboard electrical power source (310, 710A) is adapted to be charged by a batterycharger (330; 330A, 330B, 730) that in turn is adapted to be powered by an externalelectrical power source (320, 720, 750).

3. The floor surfacing machine (100, 400, 700) according to any one of theclaims 1 or 2, wherein the floor surfacing machine (100, 400, 700) comprises anonboard battery charger (330A, 730) that is adapted to charge the onboard electrical power source (310, 710A). is--edepts-ef--te--eherge--the--eafseard--eleetr-ë-eai---pevve:ß-searea--(ålä-ä)--and--ës--e-aa-neeted--te te-the--seeenei-eurrent--ej-ig) Mg. claims, wherein the floor surfacing machine (100) comprises a drive arrangement (190) The floor surfacing machine (100) according to any one of the previous configured to propel the drive wheels (171, 172), where the drive arrangement (190)comprises at least one electric motor that is adapted to be powered by means of a re-chargeable onboard electrical power source (310, 710A; 710B). íiêâ. same onboard electrical power source (310, 710A) is adapted to power the first drive The floor surfacing machine (100) according to claim girl, wherein the motor (110) and the drive arrangement (190). ifåﬁ. separate onboard electrical power source (710B) is adapted to only power the drive The floor surfacing machine (100) according to claim 44%, wherein a arrangement (190). 44:. låg, wherein the drive arrangement (190) comprises a sensing arrangement (502) that The floor surfacing machine (100) according to any one of the claims 14%,- is adapted to switch between having the drive arrangement (190) powered by theonboard electrical power source (310, 710A, 710B) or by the electrical mains (320,720) dependent en the power presentiy available from the onboard electrical powersource (310, 710A, 710B) and the electrical matris (320, 720). liäë. claims, wherein the onboard electrical power source (310) is positioned above the The floor surfacing machine (100) according to any one of the previous wheels (171, 172) such that the weight of the onboard electrical power source (310)provides a pressure of the wheels (171, 172) towards a floor (500), where said pressure is adapted to increase traction of the floor surfacing machine (100). 433.onboard electrical power source (310) is positioned such that, during operation of the The floor surfacing machine (100) according to claim iiäå, wherein the floor surfacing machine (100), an extension along a closest distance (D) between amass center (501) of the onboard electrical power source (310) and the floor (500)passes between the drive wheels (171, 172). lílg.claims, wherein the re-chargeable onboard electrical power source (310) is constitutedby a battery (310). The floor surfacing machine (100) according to any one of the previous 4311. claims, wherein the internal onboard power source (710A) is adapted to be charged by The floor surfacing machine (100) according to any one of the previous a battery charger (730) that in turn is adapted to be powered by an external electricalpower source (750) that is constituted by a 12 VDC or 24 VDC supply (750).