EP2350393B1 - Gathering street sweeper - Google Patents

Abstract

The invention relates to a gathering street sweeper for cleaning traffic surfaces, comprising a carrier vehicle (1), a dirt collecting container (3), at least one roller broom (8) which is disposed away from said container, moved with contact to the traffic surface to be cleaned relative to the same, and driven in a rotating manner, a dirt conveying section (KF) extending from the roller broom to the dirt collecting container, and at least one further broom that is driven in a rotating manner in the form of a feed broom (9). For this purpose, at least one electrostatic effect-utilizing unit is provided in the driving direction in front of at least one of the brooms (8, 9) that is driven in a rotating manner, and/or in the region of at least one of the brooms that is driven in a rotating manner, for receiving and/or binding dust particles.

Description

The present invention relates to a receiving street sweeper for cleaning traffic areas, with a carrier vehicle, a sweeping bins, at least one arranged away to this, with contact to the traffic area to be cleaned against this moving, rotatably driven roller brush, extending from the roll brush to the sweeping bins Sweeping material conveyor line and at least one further rotatingly driven broom in the form of a feed broom, in particular designed as a plate broom.

Such receiving sweeping machines are well known and widely used. By means of the at least one rotationally driven Zuführbesens, which may be designed in particular as a rotating about a typically substantially vertical axis circular brush, sweeping material is supplied to the typical known generic pickup sweeping the at least one roller brush, which is adjacent to the inflow end of the debris conveying path , As far as the configuration of the sweepings intake is concerned, a distinction is made between two principles. On the one hand, there are mechanical road sweeping machines in which the conveyance of the sweeping material through the sweeping material conveyor line passes into the sweeping material collecting containers by means of mechanically operating conveying means such as a belt conveyor takes place. On the other hand, there are suction picking road sweeping machines with a pneumatic sweeping material conveyor line, which is typically generated by a fan in the sweeping bins a negative pressure relative to the ambient pressure.

Both principles have specific advantages and disadvantages. In mechanical road sweepers is particularly advantageous that they work comparatively quiet; However, the cleaning performance is sometimes unsatisfactory in particular insofar as small and very small particles can be absorbed only to a limited extent. Especially in this regard pneumatic pick-up road sweeping machines are much more powerful, but at the cost of a significantly increased noise and a considerable energy demand for the drive of the blower. With regard to dust emissions, both principles of sweeping uptake tend to differ, especially inasmuch as mechanically absorbing street sweepers produce corresponding emissions - due to fluidized dust - predominantly on the rotatably driven brooms, whereas in pneumatic sweeping machines this emission source is not of such great importance and in particular also dust which is supplied by the suction air flow to the debris collecting container, as a result of insufficient dust separation and Retention with the exhaust air flow is blown out of the debris collection container again. Regardless of the specific execution of Kehrgutaufnahme but thus there is a dust emission problem, in this respect just the stirring up of dust by the generic street sweepers (regardless of the specific configuration of Kehrgutaufnahme) existing plurality of rotatingly driven broom, with the zu cleaning surface in contact and functionally cooperate in terms of a supply of debris by means of at least one Zuführbesens to at least one roller brush, makes a special contribution.

In order to counteract this disadvantage, ie to curb the dust emission, the traffic area to be cleaned is often wetted with water immediately before sweeping and / or water sprayed into the debris conveyor line and / or the collection, especially in pneumatically receiving street sweeping machines, which dust more or less is bound. Such a generic designed receiving sweeper is for example the US 2003/0204931 A1 removable. Although this method of moistening is quite effective for various dusts; However, it entails that the appropriate street sweeper equipped with suitable water tanks and must be refueled with water before the turnaround, which is particularly disadvantageous in so far as the available for the reception of debris useful volume and / or the corresponding payload are reduced accordingly. Also, under certain operating conditions, the water supply limits the maximum possible duration of the turnaround or the maximum possible cleaning distance before water has to be refueled.

In the light of the above-identified prior art, the present invention seeks to provide a receiving street sweeper of the type mentioned, despite a low dust emission, especially a low particulate matter emission, by a particularly high cleaning performance and just in terms of small - And smallest particles (tire abrasion, brake pad wear and the like.) Excellent, without the disadvantages associated with the dust binding by means of water.

The object set forth above is achieved in a receiving street sweeper of the type specified by at least one Zuführbesens and / or the roll broom, this assigned, at least one electrostatic effects exploiting means for receiving and / or binding of dust particles is provided which a device for electrostatic charging fluidized dust particles includes. In other words, receiving street sweeping machines according to the invention are characterized by at least one device that utilizes electrostatic effects Dust and other small and very small particles, which are whirled up by the feed broom and / or roll broom which is to be cleaned, catch and bind directly in the region of the broom, the device in question for receiving and / or binding dust particles being a device for electrostatic charging fluidized dust particles includes. In this case, in the region of the at least one respective, rotatably driven feed broom or roller broom, electrostatic charging of the dust particles already raised by the relevant feed beater or roller broom, possibly by means of a possible electrostatic charging of the feed broom or broom, can take place at least one spray electrode, which is arranged for this purpose adjacent to the respective rotationally driven feed brush or roller brush, for example, in the case of the execution of the Zuführbesens as a circular brush ring around this. The dust particles are, in particular when they are charged with the opposite polarity as the bristles of the feed or roll broom, deposited by attachment to the bristles of the relevant feed or roll broom from the air. By using such electrostatic effects to pick up, trap or bind dust particles, the use of water, as is currently being sprayed to bind dust on traffic surfaces to be swept, becomes wholly or at least predominantly unnecessary. The to be carried with a street sweeper Water supply can be reduced accordingly substantially. In addition, in accordance with the present invention, the particulate matter emissions of the street sweeper can be substantially reduced even compared to those street sweeping machines which spray water to bind dust; because due to the physical and chemical properties of the various typically encountered on traffic surfaces particulate matter and other small and very small particles, these can hardly be wetted with water, which means that just those particulate matter and other small and very small particles by - measured due to their size - comparatively large water droplets sprayed on the traffic surface are additionally whirled up. Such an effect can be avoided when using street sweepers according to the invention, which, as explained, typically do without water spraying of the traffic area. Both pneumatic and mechanical road sweepers according to the present invention, in which the device utilizing at least one electrostatic effect acts directly in the area of the at least one rotationally driven feed bale and / or the roller broom, provide significantly better cleaning results than conventional comparable street sweeping machines.

According to a preferred embodiment of the invention takes place with the electrostatic effects ausnutzenden Means a dust pickup and / or dust adhering directly to the respective feed broom or roller brush. This can be brought about in particular by the fact that the bristles of the broom, as already indicated above, are charged electrostatically. In order to enhance the effect, moreover, in the travel or working direction of the street sweeper in front of the relevant rotating broom the fine dust on the traffic surface can be charged with opposite to the charge of the broom polarity, for example using a respective broom driven rotating in the direction of travel or working direction of the street sweeper upstream spray electrode. This may possibly be identical with the below-mentioned unit for the electrostatic charging of the dust.

According to another preferred embodiment of the invention takes place with a further electrostatic effects ausnutzenden means a fine dust already in the direction of travel or working before at least one of the rotatably driven brooms (ie the at least one roller brush and / or the at least one Zuführbesen), so that the amount on fine dust, which can be whirled up by the rotating brooms, is already significantly reduced. Particularly suitable here is a - preferably without its own drive - on the ground rolling electrostatic dust collector, for example in the form of a stocked with a Langflorbesatz roller, the Langflorbesatz is electrostatically chargeable. The electrostatic dust collector is suitably associated with its own separate separation device, which in order to regenerate the dust collector, selectively removed from the dust collector (eg sucks) on this due to electrostatic forces adhering fine dust and the further processing (see below) feeds. In the case of a dust-collecting roller, the regeneration can be carried out continuously by passing the surface of the dust-collecting roller during its rotation past a separating device. The deposition of adhering to the dust collector dust in the region of the separator can be supported by locally limited electrostatic discharge or reversal of the dust collector in the region of the separator, as explained in more detail below in another context. In order to favor the uptake of the dust by the dust collector, the dust collector may be preceded by an aggregate (eg in the form of a spray electrode) in the direction of travel or working of the street sweeper, with which the particulate matter stored on the traffic surface is charged electrostatically. The advantages of such a design of the street sweeper according to the invention will be explained in more detail below in another context.

The above-explained in particular with reference to a spray electrode aspects of the charging of dust before and / or during the action of the at least one The rotating brooms apply in the same way to other forms of electrostatic charging. In that regard, for example, the spraying of the traffic area and / or the immediate vicinity of the respective rotatingly driven broom by means of an aerosol (eg water) into consideration, the aerosol mist or the droplets are electrostatically charged. The latter can be brought about, for example, by spraying the aerosol through an electrically charged grid.

Is carried out in the sense of the further development of the invention described above with the electrostatic effects exploiting device a dust pickup and / or a dust adhering directly to the at least one rotating driven feed broom and / or the roller brush or possibly with another electrostatic effects exploiting device a dust pickup and / / or a dust adhering directly to another rotatably driven broom, it is particularly advantageous if the bristles of the relevant broom driven in rotation are alternately electrostatically charged and discharged or otherwise charged during its circulation. In that first region or region (adhesion region) in which the bristles of the broom are electrostatically charged during their circulation, the dust particles whirled up by the broom adhere to the bristles. In contrast, the dust particles fall in that second area or segment (deposition area) in which the bristles of the brush during From their circulation are discharged from the bristles or can be easily removed from the bristles (eg by stripping, tapping, blowing off, suction and the like.). In particular, in the event that the congestion particles in turn by means of special measures (eg by means of a spray electrode, see above) with a certain polarity (in particular negative) are electrostatically charged, the above-mentioned effect is particularly pronounced when the bristles of the broom in the above Not only do they discharge the second-mentioned region (deposition region), but rather they are charged to the polarity in the first region of opposite polarity, so that they are actively brought to the same electrostatic potential as the dust particles. This favors the targeted, localized and well-defined removal of adhering to the bristles dust particles from the broom in the deposition area. Comparably good results can be achieved if the bristles of the relevant broom are subjected to an alternating field or an alternating voltage as they pass through the deposition area, so that their charge, namely the polarity of the charge, changes rapidly several times (charge pulsation). This helps to actively remove the dust that has accumulated on the passage of the respective bristles through the adhesive area as it passes through the separation area. The changing by the above, during one revolution of the respective rotatingly driven brush changing electrostatic polarization or charging The bristles enable locally controlled loading and unloading of the bristles with dust particles and are of great use with a view to the targeted transport of the dust particles "captured" by the broom to a certain location on the orbit of the bristles where it is exposed (eg via a localized surface) Extraction) is particularly easy to supply the dust of a downstream treatment (see below).

The loading and unloading of the bristles of the respective rotary driven broom can to a certain extent be done from the inside, i. take place over the core or carrier body of the respective broom. Another embodiment, which is likewise advantageous in practice, provides for the electrostatic charge of the bristles to be applied to them from the outside.

The street sweeper is according to a particularly preferred embodiment of the invention is a mechanically receiving street sweeper with a mechanical sweeping material conveyor line. In application of the present invention, it is possible to significantly increase the cleaning performance of such mechanically absorbing street sweeping machines and thus - at least for different applications - to make them competitive with respect to the achievable cleaning result to the louder and energetically significantly worse pneumatic pickup street sweeping machines. The Kehrgutförderung in the sweeping material conveyor line can in particular by the rotating driven Walzenbesen be effected, which in turn can be explained above, over the circulation of the bristles alternating electrostatic charging of the bristles in the sense of supporting the mechanical conveying movement can be used. By no means, however, is it imperative that (solely) the rotary driven broom causes the sweeping material to be conveyed along the sweeping material conveying path. Rather, there may be provided a different from the rotatably driven roller brush conveying unit there, in which case the rotating driven roller brush, in addition to solving the pollution from the traffic area, essentially causes a supply of the sweeping material to the sweeping material conveyor line and arranged there conveying unit. An additional device utilizing electrostatic effects can be provided in the area of such a conveying unit assigned to the debris conveying path and different from the rotationally driven roller brush, and in particular cause dust binding there. As a separate delivery unit, in particular a circulating belt conveyor, which may be equipped in particular with bristles or ribs, cause the Kehrgutförderung in the debris conveying line. In terms of implementing a second, further, electrostatic effects exploiting device, the above-stated principle of changing during one cycle electrostatic charging of the bristles can be advantageously applied to such a bristle or ribbed belt conveyor. The same applies to one Belt conveyor that has no bristles or ribs, but rather a different surface structure.

The at least one device provided according to the invention and utilizing electrostatic effects, which can be arranged to receive and / or bind dust particles, in particular in the area of at least one of the rotatably driven brooms, can also support the transport of the dusty sweeping material in the direction of the sweeping material collecting container in an advantageous embodiment , The direction of the caused by electrostatic effects movement of the dust particles corresponds in this case substantially the direction of - caused by mechanical, pneumatic or other influence - movement of the remaining sweepings. This can be achieved structurally in particular by the fact that the above-described separation of the dust particles from a broom with alternately electrostatically charged and discharged bristles takes place in that region which is closest to the sweeping material conveying path.

Also, in addition to the at least one inventively provided, electrostatic effects exploiting device, which is arranged for receiving and / or binding of dust particles in the range of at least one rotationally driven Zuführbesens and / or the roll broom, at least one further electrostatic effects exploiting device may be provided which Dust and other small and very small particles traps, binds or retains in the area of the sweeping material conveying path and / or in the area of the sweeping material collecting container. In this sense, another preferred development of the invention is characterized in that a further, additional electrostatic effects exploiting device supports the transport of dust particles in the direction of the traffic area to the waste collection, especially in the area of debris conveyor line.

However, a device provided in the region of the conveying path that utilizes further electrostatic effects does not have to be in a corresponding electrostatically loadable design of the delivery unit itself. Rather, it can be provided by independent electrostatic effects exploiting facilities, such as in particular electrostatic dust collector. This also applies to the pneumatic pick-up street sweeping machines according to the invention explained in more detail below.

According to another preferred variant of the invention, the street sweeper is an intake sweeping street sweeper with a pneumatic sweeping material conveyor line. The points discussed above in connection with mechanically absorbing road sweeping machines here apply essentially in a corresponding manner with the proviso that the promotion of the sweeping material along the sweeping material conveyor line through the between the sweeping material collection and the environment existing pressure difference occurs. Thus, the rotary driven broom has mainly only a contamination of the traffic area dissolving and the debris to the pneumatic sweeping material conveyor line feeding function, while the function of Kehrgutförderung along the debris conveyor line occurs in the background.

It has already been explained above that the dust raised by the at least two rotationally driven brooms which are in contact with the traffic area to be cleaned is particularly advantageously "caught" immediately in the area of at least one of the relevant brooms. In this sense, it is particularly advantageous when in pneumatic receiving street sweeping machines according to the invention, a parallel to the pneumatic sweeping material conveyor line dust extraction in the area of the rotating broom opens. Preferably, the relevant rotating broom is covered with a scoop; This increases the efficiency of the opening in the area of the relevant broom to the pneumatic sweeping material conveyor line parallel dust extraction. The latter can be tuned specifically with regard to its operating parameters (negative pressure, air flow rate, line cross-sections) to the dust to be sucked off in the area of the relevant broom alone. Of even greater advantage in terms of a particularly environmentally friendly sweeping operation is, however, if in the area of the opening close to the broom parallel dust extraction a separate Aggregate for dust separation (eg cyclone or wet scrubber) or other (eg chemical) dust treatment is provided, which is tuned to the specific mechanical, physical and / or chemical properties of the stirred by the respective rotating broom dust particles. The optionally provided in the vicinity of the opening parallel to the broom parallel dust extraction unit for dust separation may in particular consist of an electrostatic dust, in which case it is particularly favorable if the dust particles stirred up by the broom upstream of the dust, for example in the vicinity of the broom to be electrostatically charged by technical means (such as a spray electrode).

A specifically tailored to fine and ultrafine dust extraction is also favorable in such street sweeping machines according to the invention, which have a mechanical sweeping material conveyor line. Here, the relevant portion of the recorded debris is fed quietly and with low energy consumption mechanically the sweeping material collection container, whereas only a small proportion of the sweeping material, namely dust-like particles are pneumatically conveyed. The suction fan can be dimensioned correspondingly small in this case and operated with low energy consumption and low noise emissions.

The points of view set out above apply correspondingly to a picking up of dust from the traffic area by means of a separate dust collector (see above) in the travel or working direction before the broom. Here it is particularly advantageous when in pneumatic receiving street sweeping machines according to the invention, a parallel to the pneumatic sweeping material conveyor line dust extraction in the region of the dust collector associated with the separator opens. In the parallel dust extraction expediently specific units for dust separation or dust treatment are arranged.

Electrostatic effects exploiting facilities can be used in the context of advantageous developments of the present invention with great benefit not only in driving or working direction of the street sweeper in front of at least one of the rotatably driven brooms and / or in the range of at least one of the rotatably driven brooms (ie in the Kehrgutaufnahme), but, as already stated, in addition, in the area of the sweeping material conveyor line, ie during the transport of debris, and also in the field of sweepings collection container. In this sense, a further preferred development of the invention is characterized by the fact that with a further, electrostatic effects exploiting device dust retention in the sweeping material collection takes place. Here, various concretisations, if necessary also in combination with each other, can be used profitably.

According to a first preferred embodiment, if the street sweeper according to the invention is a pneumatic sweeping machine, at least one electrostatically operating dust separator is provided in the area of the exhaust air duct for the exhaust air leaving the sweeping material collecting tank. This can be provided in particular upstream of the suction fan, for example in the form of an electrostatically charged leaf strainer.

Regardless of the basic design of the street sweeper (mechanically or pneumatically receiving) can be electrostatically charged according to another preferred embodiment of the invention, the inner wall of the waste collection bin to retain particulate matter contained therein otherwise. The inner wall of the sweeping collection container, which in this case preferably has a multi-shell wall structure, then forms a large-scale collecting electrode. Their polarity is preferably selectively switchable, which - by changing the polarity - favoring removal of adhering to the inner wall of the waste collection bin dust when emptying the sweepings collection container.

Instead of or possibly in addition to such an electrostatic charging of the inner wall of the sweeping material collecting container may adjacent to this and / or more or less on the interior of the sweeping material collection container distributed to be provided separately electrostatically charged dust collector. For their function, the above-explained aspects apply in a corresponding manner. Incidentally, in turn, that the dust retention in the bunker serving electrostatic effects ausnutzende device is preferably tuned with respect to their operating parameters to another electrostatic effects exploiting device, namely one that favors the dust directly on the broom. In that regard, it is only for the sake of completeness to point out that, as is clear in the light of the above explanations of the invention for a person skilled in the art, a street sweeper according to the invention may well be equipped with several electrostatic effects exploiting facilities.

For the sake of completeness, it is pointed out that traffic areas within the meaning of this application are by no means to be understood solely as street and other land transport areas (eg sidewalks). Rather, air traffic areas (apron, runways and runways) of airports are traffic areas within the meaning of the present application, so that street sweepers according to the invention can by no means only be designed as street sweeping machines in the narrower sense but more particularly also as street sweeping machines in a broader sense.

Also for the sake of completeness, it is stated that the carrier vehicle according to the invention does not necessarily have to be a self-contained vehicle independent of the sweeping unit. Rather, the street sweeper according to the invention may also be a so-called compact sweeper with integrated carrier vehicle. Likewise, the host vehicle need not be a self-propelled, i. act vehicle equipped with a drive motor. Rather, in the sense of the execution of the street sweeper according to the invention as a trailer sweeper and non-motorized, towed vehicles form suitable carrier vehicles.

Fig. 1

in Seitenansicht eine aufnehmende Straßenkehrmaschine nach dem Stand der Technik,

Fig. 2

die Straßenkehrmaschine gemäß Fig. 1, umgerüstet zu einem ersten Ausführungsbeispiel einer erfindungsgemäßen Straßenkehrmaschine durch Anbau einer elektrostatische Effekte ausnutzenden Einrichtung zum Einfangen und Abscheiden durch den Zuführbesen aufgewirbelten Staubes,

Fig. 3

die Straßenkehrmaschine gemäß Fig. 1, umgerüstet durch frontseitigen Anbau eines elektrostatische Effekte ausnutzenden Staubsammlers, wie er zusätzlich zu der in Fig. 2 veranschaulichten Ausstattung vorgesehen sein kann,

Fig. 4

in schematischer Darstellung einen im Rahmen der vorliegenden Erfindung einsetzbaren elektrostatisch wirkenden Walzenbesen,

Fig. 5

den Walzenbesen nach Fig. 4 im Einsatz,

Fig. 6

in Seitenansicht ein im Rahmen der vorliegenden Erfindung einsetzbares elektrostatisch wirksames Förderband im Einsatz,

Fig. 7

einen im Rahmen der vorliegenden Erfindung einsetzbaren elektrostatisch wirksamen Kehrgutbehälter im Einsatz (Fig. 7a) sowie bei der Entleerung (Fig. 7b) und

Fig. 8

das gesamte Kehrsystem einer weiteren bevorzugten Ausführungsform der erfindungsgemäßen Straßenkehrmaschine.

In the following, the present invention will be explained in more detail with reference to preferred embodiments illustrated in the drawing. It shows

Fig. 1

in side view of a receiving street sweeper according to the prior art,

Fig. 2

the street sweeper according to Fig. 1 converted to a first embodiment of a street sweeper according to the invention by mounting a device utilizing electrostatic effects for the capture and separation of dust raised by the feeder broom,

Fig. 3

the street sweeper according to Fig. 1 , converted by front attachment of an electrostatic effects exploiting dust collector, such as he in addition to the in Fig. 2 illustrated equipment may be provided

Fig. 4

a schematic representation of an applicable in the context of the present invention electrostatically acting roller brush,

Fig. 5

the roller broom after Fig. 4 in action,

Fig. 6

in side view, an electrostatically active conveyor belt which can be used in the context of the present invention,

Fig. 7

a usable in the context of the present invention electrostatically effective hopper in use ( Fig. 7a ) as well as during emptying ( Fig. 7b ) and

Fig. 8

the entire sweeping system of another preferred embodiment of the street sweeper according to the invention.

After the in Fig. 1 Illustrated, well-known prior art, to which the present invention can attach by implementing additional components, the street sweeper comprises a carrier vehicle 1 and a receiving sweeping unit constructed thereon 2. The sweeping unit comprises a sweeping bins 3 having disposed therein, in Fig. 1 not shown suction fan. The sweeping material collecting container 3 is connected via a suction hose 4 with a suction mouth 6 arranged on a suction carriage 5. In the direction of travel in front of the suction mouth 6, a broom 7 in the form of a rotating brush roller 8 is arranged. On the side next to the broom 7 a Zuführbesen 9 is provided in the form of a rotary driven Tellererbesens 10. The suction carriage 5 with the suction mouth 6 and the suction hose 4 are part of a sweeping material conveying path KF. After the in Fig. 1 Road sweeper shown in this respect corresponds to the well-known state of the art, further explanations are unnecessary.

According to the in Fig. 2 illustrated embodiment of the invention, the Zuführbesen 9 over a substantial part of its circumference by means of a bell-shaped suction hood 23 sheathed. The interior of the suction hood 23 is connected to the sweeping material collecting container 3 via a suction hose 24, which is part of a dust extraction S which is functionally parallel to the sweeping material conveying path KF, and an upstream dust separator 25. The dust separator 25 has specific separation elements (cyclones, filters and the like), which are designed for separating fine and very fine dusts from the air stream flowing through the suction hose 24.

In the direction of travel in front of the feed brush a rod-shaped spray electrode 26 is arranged, which is fixed by means of the electrode holder 27 on the suction hood 23. The entrapment of fluidized dust by the bristle trim 28 of the pan 10 is promoted by electrostatic charging of the bristles. In the sense of the embodiment explained above and described below in another context, the bristles are In the process, electrostatically charged only over a portion of its circulation, but discharged from the suction hood 23 adjacent to the air extraction.

According to Fig. 3 the street sweeper is equipped with a front mounted dust collector 11, as it - can be provided on road sweeping machines according to the invention - as an additional electrostatic effects exploiting device. The dust collector 11 comprises a freely rotatably mounted on two lateral support arms 12, resting on the road surface F dust pickup roller 13. The dust pickup roller 13 can be superficially electrostatically charged by means of an electric unit 14. As a result, the adhesion of dust to the dust pickup roller 13 is improved so that it picks up dust from the road surface F.

As seen in the direction of travel behind the contact area K, in which the rolling on the road surface F rolling dust pickup roller 13 touches the road surface, a dust collecting device 15 is arranged. This comprises a arranged in the immediate vicinity of the surface of the dust pickup roller 13 suction head 16, which is connected via a hose 17 and an intermediate dust collector 18 to the sweeping material collecting container 3. The suction head 16 and the hose 17 are part of a dust extraction S which is functionally parallel to the sweeping material conveying path KF. The dust separator 18 contains specific dust separation units such as cyclones, filters and the like.

In order to favor that the dust picked up from the road surface F by means of the dust pickup roller 13 is removed from the dust pickup roller 13 by means of the suction head 16, a discharge device 19 is disposed opposite to the suction port of the suction head 16 by which the electrostatic charge of the dust pickup roller 13 is locally neutralized. ie the electrostatic charge of the dust pickup roller 13 is reduced. Also contemplated is a localized reversal of the charge of the dust picking roller to actively repel the dust particles adhering to it in the region of the suction head 16.

The two support arms 12 are otherwise extended beyond the axis 20 of the dust pickup roller 13 out to the front. The two respective extensions 21 carry a rod-shaped spray electrode 22 extending transversely to the direction of travel in front of the dust pickup roller 13, by means of which an electrostatic charge of the dust particles deposited on the road surface F is possible. The electrostatic charge is carried out with a reverse to the charging of the dust pickup roller 13 by the electrifying unit 14 polarity.

Fig. 4 illustrates the preferred in the context of the present invention used electrostatic charging of the bristle 28 of a broom 29, here a roll broom, only over a portion of the Circulation A about the axis of rotation 30. And that takes place an electrostatic charge of the bristles of the bristle trim 28, just before they touch the road surface F during its rotation about the axis 30 in the contact area K. The electrostatic charge is maintained over an angle α of about 270 °. Then, a discharge of the bristles of the bristle lining takes place, so that the dust adhering to the bristles can be easily removed from the bristles and into the dust collecting container 31. For this purpose, the bristles are stripped off the wiping plate 32 of the dust collecting container 31. By electrostatic discharge of the bristles of the bristle facing 28 over the approximately 90 ° amounting angular range β and the electrostatic charge of the dust collection container 31, an effective dust transport from the road surface F to the dust collection container 31. Visible can also be the result of an electrostatic charge on the road surface F deposited dust in the direction of the broom 29 are promoted by means of a spray electrode 33. The corresponding effect is in Fig. 5 illustrated.

The above-explained principle of spatially limited electrostatic charging and discharging or the above-described spatially limited opposite polarity electrostatic charge of the rotary driven broom can be seen with corresponding advantage transmitted to oscillating brooms.

Fig. 6 shows the matching principle transferred to a equipped with a bristle 34 conveyor belt 35 which rotates about two pulleys 36 and 37 Again, there is an electrostatic charge of the bristles of the bristle trim 34, just before the bristles in the contact zone K contact the road surface; and a discharge of the bristles of the bristle lining takes place just before the bristles reach the scraping plate 32 of the dust collecting container 31.

To Fig. 7 the sweeping material collecting container 3 is lined adjacent to its inner wall with an electrostatically chargeable structure 38. At this structure forming a dust collector 38, as long as it - is charged electrostatically during the sweeping operation of the relevant street sweeper, adheres to dust. The corresponding dust is thus effectively and sustainably separated from the air flow, which enters through the suction hose 4 into the sweeping material collecting container 3 and leaves it again via the suction fan 39. To empty the sweepings collection 3, as in Fig. 7b illustrates discharging the electrostatic chargeable structure 38 so that the non-adherent dust can be dumped together with the remaining debris.

This in Fig. 8 schematically illustrated, for installation on a known as such carrier vehicle (see. Fig. 1 ) comprises certain sweeping system - in the direction of travel or working A of the road sweeper concerned - First, an (optional) dust collector 11, then at least one designed as a disc brush 10, rotating driven Zuführbesen 9, further a rotatably driven roller brush 8, then a debris conveying path KF and finally an (optional) Feinsaugleiste 40. The dust collector 11 takes this above in connection with in Fig. 2 has already been explained, taking advantage of electrostatic effects dust on the road surface F on. By means of the disc brush (s) 10, debris is fed to the roller brush 8. The roller brush 8 interacts functionally with the debris conveying path KF. This is designed as a mechanical debris conveyor 41 and includes an inclined conveyor bottom 42 and a two rollers 43 and 44 encircling, occupied with ribs 45 conveyor belt 46. The conveyor bottom goes forward into a collecting plate 47, on which the broom 8 the debris KG throws, which is there detected by the ribs 45 of the conveyor belt 46 and transported along the conveyor floor 42 upwards into the sweeping material collecting container 3. By means of the Feinsaugleiste 40 Feischmutz is taken up by the road surface F, especially in the form of such dust-like particles that were only on the road surface F loosened by the mechanical action of the rotating broom (Zuführbesen 9 and / or roller brush 8) and therefore not already of could be added to the dust collector 11. In addition to the dust collector 11 also use the Zuführbesen 9 and the Walzenbesen 8 for recording and Binding of dust particles electrostatic effects, as already explained above. The loading of the dust pickup roller 13 of the dust collector 11, the plate recess 10 and the roller broom 8 in the sense of the above set out in detail targeted, area-wise loading and unloading by means of the electrostatic aggregate 48, to which the respective components are connected.

In the sweeping bins 3, a dust container 49 is integrated in the form of a separated space. In the dust container 49, a delivery channel 50, within which a fan 51 is disposed and to the - via corresponding suction lines 52 and 53 - both serving for the regeneration of the dust pickup roller 13 suction head 16 (see. Fig. 2 ) and the Feinsaugleiste 40 are connected. By means of a dust collector 49 associated Abscheideaggregats 54, which may be exemplified as arranged in the dust container 49 cyclone Z, the dust collected on the dust collector 11 and the Feinsaugleiste 40 from the road surface F dust from the conveying channel 50 by flowing air is deposited. The separate from the other, via the sweeping material conveyor line KF conveyed in the waste collection 3, the separate handling and caching of the dust allowed to subject the latter, if necessary, a special treatment. The latter is particularly advantageous if the dust contains primarily problem substances that are the treatment of the remaining sweepings (eg foliage composting) should be withdrawn. This in Fig. 8 illustrated sweeping system is highly efficient and environmentally friendly in this way, the compared to conventional pneumatic sweeping machines substantially reduced performance of the blower has a very positive effect both in terms of energy consumption of the street sweeper and in terms of their noise emissions.

Claims (15)

1. A gathering street sweeper for cleaning traffic areas, with a carrier vehicle (1), a sweepings collection container (3), at least one rotatively driven roller broom (8) that is arranged distant from said sweepings collection container and moved in contact with and relative to the traffic area to be cleaned, a sweepings conveying section (KF) that extends from the roller broom to the sweepings collection container and at least one other rotatively driven broom that serves as a feed broom (9) and is realized, in particular, in the form of a circular broom,
   characterized in
   that a device utilizing electrostatic effects is provided in the region of at least one feed broom (9) and/or the roller broom (8) and assigned thereto, wherein said device serves for gathering and/or binding dust particles and comprises a device for electrostatically charging whirled-up dust particles.
2. The street sweeper according to Claim 1, characterized in that the device utilizing electrostatic effects causes dust to directly gather on and/or adhere to the corresponding feed broom (9) or roller broom (8).
3. The street sweeper according to Claim 2, characterized in that the bristles of the feed broom (9) or roller broom (8) are electrostatically charged differently in an alternating fashion during the revolution of the broom, namely electrostatically charged in a first fashion while passing through a first region and electrostatically discharged while passing through a second region, electrostatically charged with an opposite polarity referred to the electrostatic charge in the first region or alternately charged with different polarity (alternating polarity).
4. The street sweeper according to one of Claims 1 to 3, characterized in that another device utilizing electrostatic effects promotes the transport of dust particles in the direction from the traffic area to the sweepings collection container (3) in the sweepings conveying section (KF).
5. The street sweeper according to one of Claims 1 to 4, characterized in that the street sweeper consists of a mechanically gathering street sweeper with a mechanical sweepings conveying section (41) that comprises a mechanical conveying unit.
6. The street sweeper according to Claim 5, characterized in that another device utilizing electrostatic effects causes dust to bind on the mechanical conveying unit
7. The street sweeper according to Claim 5 or Claim 6, characterized in that the conveying of sweepings in the mechanical sweepings conveying section (41) is realized with a revolving belt conveyor.
8. The street sweeper according to one of Claims 5 to 7, characterized in that a pneumatic sweepings conveying section leading into the sweepings collection container (3) or a separate dust container (49) is provided in addition to the mechanical sweepings conveying section (41) and preferably comprises a dust suction arrangement leading into the region of at least one feed broom (9).
9. The street sweeper according to Claim 8, characterized in that a separate dust separation unit (25) is provided in the region of the dust suction arrangement and adapted to the specific mechanical, physical and/or chemical properties of the dust particles that are whirled up by the feed broom (9) and, if applicable, electrostatically charged.
10. The street sweeper according to one of Claims 1 to 9, characterized in that a dust retention is realized in the sweepings collection container (3) by means of another device utilizing electrostatic effects.
11. The street sweeper according to one of Claims 1 to 10, characterized in that electrostatic dust separators are provided in the region of the sweepings conveying section (KF).
12. The street sweeper according to one of Claims 1 to 11, characterized in that another device utilizing electrostatic effects in the form of a dust collector (11) is provided and gathers fine dust in front of at least one of the rotatively driven brooms (8, 9) referred to the driving or working direction (A).
13. The street sweeper according to Claim 12, characterized in that a unit (22) for electrostatically charging dust particles settled on the traffic area is arranged in front of the dust collector (11) referred to the driving or working direction (A).
14. The street sweeper according to one of Claims 1 to 13, characterized in that a device (26) is provided that electrostatically charges dust settled on the traffic area in front of at least one of the rotatively driven brooms (8, 9) referred to the driving or working direction (A) of the street sweeper.
15. The street sweeper according to one of Claims 1 to 14, characterized in that at least the rotatively driven broom (8, 9), to which the at least one device utilizing electrostatic effects for gathering and/or binding dust particles is assigned, is fitted with a mixed bristle arrangement with bristles consisting of different materials.

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