EP3456882A1

EP3456882A1 - Apparatus for the application of a substance to a ground surface

Info

Publication number: EP3456882A1
Application number: EP17191043.3A
Authority: EP
Inventors: Tero Tarmo Vilhelm Tupala; Teemu Eino Johannes Tupala
Original assignee: Aebi Schmidt Deutschland GmbH
Current assignee: Aebi Schmidt Deutschland GmbH
Priority date: 2017-09-14
Filing date: 2017-09-14
Publication date: 2019-03-20

Abstract

An apparatus for the application of a substance to a ground surface, such as a road, comprises a frame (1) and a substance distributing assembly (2) mounted thereon. The substance distributing assembly (2) comprises a granulate hopper (10), a granulate dosing unit (11) connected to said granulate hopper (10), and a rubbing unit (12) with an annular rubbing element (13). The annular rubbing element (13) contacts the ground surface along an arcuate rubbing zone (22) and is driven to rotate about an axis (X) upstanding from the ground surface. The granulate dosing unit (11) comprises an outlet positioned to discharge the dosed granulate into the inner of the rotating annular rubbing element (13).

Description

The present invention relates to an apparatus for the application of a substance to a ground surface, such as a road, comprising a frame and a substance distributing assembly mounted thereon, wherein the substance distributing assembly comprises a hopper and a dosing unit connected to said hopper.
There are widely known in the prior art different types of substance application apparatus identified above. For example, such apparatuses are used for winter road maintenance namely, for spreading grit and/or (dry or wetted) salt. Typically, such winter road maintenance apparatuses comprise at least one rotating spreading disk to which the spreading material is conveyed in a dosed manner by a worm conveyor or a band conveyor.
For various applications, the results achievable with prior art substance application apparatus are not satisfactory. This applies particularly in the field of road cleaning after oil or fuel spill. Specifically, there are not available apparatuses which meet all existing needs especially in the motor sport road cleaning, which need include high speed road cleaning with highest efficiency.
The present invention aims at overcoming this shortage.
The above object is achieved by the apparatus defined in claim 1. Accordingly, there is characteristic for the apparatus of the present invention, in addition to the features mentioned above in the introductory paragraph, that the hopper is a granulate hopper, the dosing unit is a granulate dosing unit, and there is a rubbing unit with an annular rubbing element contacting the ground surface along an arcuate rubbing zone and driven to rotate about an axis upstanding from the ground surface, the granulate dosing unit comprising an outlet positioned to discharge the dosed granulate into the inner of the rotating annular rubbing element.
Accordingly, the present invention focusses on the application of substances for the removal of oil and fuel (such as gasoline and petrol) spill from roads in the form of material in granulate form, which is advantageous in various regards including storage and dosing. Simultaneously, the apparatus of the present invention allows for particularly high efficiency in terms of both, material consumption and time need, since the granulate material is effectively crushed, directly on the surface to be cleaned, into small pieces, which small pieces have a huge active surface and are small enough to enter into finest surface cracks and neutralize even there oil and/or fuel spill. With other words, the highly effective cleaning of roads and other traffic surfaces from oil and/or fuel spill is made possible, making use of the apparatus of the present invention, by crushing in-situ (i.e. immediately on the road surface) of the applied granular material such that the latter is broken-up into small pieces and fragments, respectively, and the latter being extremely intensively rubbed even into the smallest rifts and fissures of the road surface structure. A further aspect in terms of efficiency is that the granulate material applied to the surface in dispute is not distributed beyond just a strictly confined area defined by the dimensions of the rotating annular rubbing element; e.g., there is no unintentional loss of material by wind effects or the like.
According to a first preferred embodiment, the rubbing element is flexible. Thereby, the rubbing element can somewhat deform in reaction to a non-even ground surface, e.g. a slightly arched road surface. This is beneficial as local gaps between the rubbing element and the ground surface, through which granulate material might escape, are avoided. And, even more important, the result of rubbing and thereby crushing the granulate material is more homogeneous than in case of a stiff, non-flexible rubbing element. According to an even more preferred embodiment, the rubbing element is inflatable. By variation of the inflation pressure, the flexibility of the rubbing element may be adapted to the individual conditions, i.e. the evenness or un-evenness of the to-be-treated ground surface, in the individual mission or application. For example, the rubbing unit may comprise a rigid hub member assembled at its periphery with the flexible (e.g. inflatable) rubbing element. The rigid hub member maintains a ring-shaped gap to the ground surface in order to guarantee that it is only the flexible rubbing element which contacts the ground surface.
For typical applications, the axis about which the annular rubbing element rotates may extend at least essentially perpendicular to the ground surface, resulting in a closed annular configuration of the rubbing zone. This embodiment is particularly advantageous in terms of minimum granulate consumption. However, in view of other aspects of practical importance, there may be still more advantageous if the rotation axis is oriented noticeably inclined to the ground surface, such that there is no closed annular configuration of the rubbing zone, the arcuate rubbing zone rather being lunulate extending along only a portion of a closed annular configuration. Preferably, the said portion is between 65% and 95%, particularly preferably between 75% and 85% of a closed annular configuration. Such distinct partly-annular, lunulate rubbing zone results in more homogeneous operating conditions especially in case of distinctly uneven ground surfaces. The risk of granulate spill through the local gap between the rubbing element and the ground surface may be minimized by positioning the dosing unit outlet in vicinity to the centre of the lunulate rubbing zone. According to a most preferred variation, the "opening" of the lunulate rubbing zone is in the front region, i.e. forwardly in the working direction, such that at least a substantial portion of granulate material escaping from the inner of the annular rubbing element through said "opening" to ahead of the rubbing element will nevertheless afterwards be captured and crushed by the progressing rubbing element.
According to another preferred embodiment, a plurality of rotating ground contacting granulate material distributing elements are arranged in the inner of the annular rubbing element. Such granulate material distributing elements, which may for example be brush-like comprising a plurality of bristles, promote a more homogeneous pre-distribution of the granulate material applied to the ground surface by the granulate dosing unit, what is beneficial for the effective crushing of the granulate material by the rubbing element. In case the annular rubbing element is born by a hub element (see above), the said granulate material distributing elements are preferably connected to the rubbing element hub member.
According to still another preferred embodiment, the rubbing unit is rotatably born by a support which is articulated to the frame. Depending on the individual needs and construction, the support may be one-axis articulated or even two-axis articulated. The articulated support allows for a kind of floating of the rubbing unit with regard to the frame such that is can best follow the individual local geometry of the ground surface, independently of the frame. As a consequence, such a floating mounting of the rubbing unit with regard to the frame has positive effects to the performance of the apparatus of the present invention.
While, as set out above, the rubbing unit is preferably floatingly mounted to the frame, the granulate hopper is preferably immovably mounted to the frame. With other words, there is preferably possible some degree of displacement of the rubbing unit relative to the granulate hopper.
Still another preferred embodiment of the invention is coined by the frame being part of a base structure additionally comprising wheels and wheel suspensions. E.g., such base structure may be adapted for front-side mounting to a commercial vehicle. According to another preferred embodiment, the said base structure is a trailer base structure additionally comprising a hitch. In this instance, any articulated support of the rubbing unit by the frame (see above) allows for floating of the rubbing unit at least about a horizontal axis perpendicular to the working direction. This allows, e.g., for compensation of different heights of the trailer coupling of the towing vehicle such that individually different heights do not affect the uniform contact pressure distribution around the rubbing element on the ground surface.
In the above discussed case where the frame is part of a base structure additionally comprising wheels and wheel suspensions, the latter may be adjustable and/or comprise levers articulated to the frame to swivel about a horizontal axis. By variation of the wheel suspensions, e.g. by swivelling the wheel suspension levers about the respective axis, the frame may be lifted or lowered, respectively. Thereby, the rubbing element may be easily brought into contact with the ground surface (n the working mode of the apparatus) or out of contact with the ground surface (in the transport mode of the apparatus). Moreover, such variation of the wheel suspensions allows for easy adjustment, in reaction to the individual circumstances, of the contact pressure of the rubbing element on the ground surface in the working mode. In this regard, the wheel suspensions may even be self-adjusting in the meaning that they automatically maintain a predetermined contact pressure of the rubbing element on the ground surface, regardless of the decrease of the total weight of the granulate hopper during the mission as a result of continued distribution of granulate material. Even if there is no option for any (manual or automatic) wheel suspension adjustment discussed above, there may be provided for such maintaining a predetermined contact pressure of the rubbing element on the ground surface. E.g., the apparatus of the invention may comprise a proper pressing unit acting on the rotating annular rubbing element and maintaining a predetermined contact pressure of the rubbing element on the ground surface. The pressing unit, which may, e.g., comprise springs or the like, may in particular abut against the frame.
According to still another preferred embodiment, the apparatus of the present invention may comprise a camera monitoring the inner of the rubbing element. The respective picture may be displayed on a suitable screen in the driver cabin of a vehicle on which the apparatus is mounted or by which the apparatus is towed in order to allow the driver to monitor the proper function of the apparatus.
In the following, the present invention is explained with regard to the drawing illustrating a preferred embodiment thereof. In the drawing

Fig. 1: shows a front-top perspective view of a trailer equipped with an apparatus of the present invention,
Fig. 2: shows a rear-top view of the trailer of Fig. 1,
Fig. 2a: shows a detail of Fig. 2 in an enlarged scale,
Fig. 3: shows a combined side elevation view (front and rear part) of and cut (centre part) through the trailer of Figs. 1 and 2,
Fig. 4: shows a perspective view of the rubbing unit support, and
Fig. 5: shows a perspective view of a turntable rotatably born by the rubbing unit support.

The drawing, illustrating a preferred embodiment of the present invention, shows an apparatus for the application of granulate material to a ground surface, such as a road, comprising a frame 1 and a substance distributing assembly 2 mounted thereon, whereby the frame 1 is part of a trailer base structure additionally comprising (at its front end) a hitch 3 and (at its rear end) wheel suspensions 4 with wheels 5. The frame 1 comprises two longitudinal lateral bars 6, a front transverse bar 7, a rear transverse bar 8, and a pair of front triangular bars 9 with the hitch 3 at the tip thereof.
The substance distributing assembly 2 comprises a granulate hopper 10, a granulate dosing unit 11 connected to said granulate hopper 10, and a rubbing unit 12 with an annular rubbing element 13 driven to rotate about an axis X. The granulate hopper 10, which is immovably mounted to the frame 1 (i.e. the front transverse bar 7 and the rear transverse bar 8 thereof) via a front stand 14 and a rear stand 15, comprises an upper, cylindrical portion 16 and a lower, conical portion 17. The granulate dosing unit 11 is connected to the hopper 10 at the bottom end of the conical portion 17 and comprises a granulate outlet more or less above the centre of the annular rubbing element 13, such that the granulate dosing unit 11 expels the dosed granulate into the inner of the rotating annular rubbing element 13. A dosing slide 18 driven by a hydraulic cylinder 19 (or an electric linear drive) is movable, in a stepless manner, between a first end position with fully open granulate outlet and a second position with fully closed granulate outlet, thereby allowing to vary the discharge opening and the granulate flow passing therethrough.
In addition to the annular rubbing element 13, the rubbing unit 12 comprises a rigid hub member 20. In the illustrated embodiment, the hub member 20 is designed similar to the peripheral portion of a vehicle wheel rim. The rubbing element 13 itself, which is assembled to the hub member 20, is in the form of a vehicle tyre, i.e. it is flexible and inflatable. That particular wall portion 21 of the rubbing element 13 which faces the ground surface forms the annular rubbing zone 22 which may contact, along a closed ring-shaped contact zone, the ground surface in the working mode of the apparatus, i.e. with the rubbing element 13 lowered such that it contacts the ground surface (see below). Equally distributed in the inner of the annular rubbing element 13, there are four brush-like granulate distributing elements 23, the bristles 24 of which are for contacting the ground surface when also the rubbing element 13 is in ground surface contact. The granulate distributing elements 23 are connected to the hub member 20, such that they rotate together with the rubbing unit 12 about the axis X.
The wheel suspension assembly allows to lift and lower the frame 1, such that there are two different modes of the apparatus namely, a transport mode (illustrated in the drawing) with the frame 1 lifted and the rubbing element 13 out of contact to the ground surface, on the one hand, and a working mode with the frame 1 lowered and the rubbing element 13 in contact to the ground surface, on the other hand. To achieve this, the wheel suspension axle 25 is born by two levers 26 which are articulated to the frame 1 to swivel about a horizontal axis Y perpendicular to the working direction A. A height adjustment drive D in the form of a hydraulic cylinder 27 extends between the granulate hopper rear stand 15 and the axle 25. By variation of the hydraulic cylinder length, the angular position of the wheel suspension unit 28 (axle 25 and levers 26) with respect to the frame 1 may be altered resulting in alteration of the altitude of the frame 1 above the ground surface.
While the granulate hopper 10 is immovably mounted to the frame 1, the rubbing element 13 is one-axis articulated to the latter. To this end, a rubbing element support 29 comprising a collar portion 30 and a ring-shaped lid portion 31 is born by the frame 1 such that it may swivel about a horizontal axis Z extending perpendicular to the working direction A. In detail, the support 29 comprises two bolts 32 fixed, by brackets 33, to the support lid portion 31 and rotatably received in bearings 34 which are provided in two lugs 35 mounted to the longitudinal lateral bars 6 of the frame 1. The support 29 comprises six grooved pulleys 36 extending through windows 37 in the support collar portion 30. Said grooves 38 engage a (radially inner) rim portion 39 of a turntable 40 such that the latter is born rotataby about axis X. To rotate the turntable 40, a hydraulic motor 41 is mounted to a respective lug 42 provided at the support 29. A pinion 43 driven by said hydraulic motor 41 meshes with a sprocket gearing 44 provided at the outer periphery of the turntable 40. The turntable 40 comprises four mounting brackets 45 at which the rubbing element 13 is fixed to the turntable 40. By the articulating hinge suspension of the rubbing element support 29 at the frame 1, there may be compensated for any alteration in the inclination of the frame 1 induced by either of lifting and lowering of the frame as discussed above and alteration of the height of the vehicle coupling, such that the axis X of rotation of the rubbing element 13, in use of the apparatus with the rubbing element 13 contacting the ground surface, automatically extends perpendicularly to the ground surface to provide for a uniform pressure of the rubbing element 13 to the ground surface along the entire annular rubbing zone 22.
To achieve a result of utmost quality and reproducibility, the wheel suspension unit 28 may be self-adjusting for continuously maintaining a predetermined contact pressure of the rubbing element 13 on the ground surface. To this end, there may be provided for a control acting on the height adjustment drive 26 in response to the signal of a pressure transmitter.
Close to the front end of the trailer, a box 46 is mounted to the frame 1 housing the hydraulic and control equipment such as the hydraulic tank 47, hydraulic pump 48, valve block, and the like. Additional, more peripheral optional equipment is also illustrated in the drawing including a camera 49 mounted at support 29 monitoring the inner of the rotating rubbing element 13, a camera 50 monitoring the ground surface behind the trailer, a warning lamp (beacon) 51, rear lights 52, batteries 53, and a hopper vibrator 54 to promote uniformity of granulate flow.

Claims

Apparatus for the application of a substance to a ground surface, such as a road, comprising a frame (1) and a substance distributing assembly (2) mounted thereon, wherein the substance distributing assembly (2) comprises a granulate hopper (10), a granulate dosing unit (11) connected to said granulate hopper (10), and a rubbing unit (12) with an annular rubbing element (13) contacting the ground surface along an arcuate rubbing zone (22) and driven to rotate about an axis (X) upstanding from the ground surface, the granulate dosing unit (11) comprising an outlet positioned to discharge the dosed granulate into the inner of the rotating annular rubbing element (13).
Apparatus according to claim 1, wherein the rubbing element (13) is flexible.
Apparatus according to claim 2, wherein rubbing element (13) is inflatable.
Apparatus according to claim 2 or claim 3, wherein the rubbing unit (12) comprises a rigid hub member (20) assembled with the flexible rubbing element (13) and maintaining a ring-shaped gap to the ground surface.
Apparatus according to any of claims 1-4, wherein a plurality of rotating ground contacting granulate distributing elements (23) are arranged in the inner of the annular rubbing element (13).
Apparatus according to claims 4 and 5, wherein the granulate distributing elements (23) are connected to the hub member (20).
Apparatus according to claim 5 or claim 6, wherein the granulate distributing elements (23) are brush-like comprising a plurality of bristles (24).
Apparatus according to any of claims 1-7, wherein the rubbing unit (12) is rotatably born by a support (29) which is articulated to the frame (1).
Apparatus according to claim 8, wherein the support (29) is at least one-axis (Z) articulated, preferably two-axis articulated.
Apparatus according to any of claims 1-9, wherein the granulate hopper (10) is immovably mounted on the frame (1).
Apparatus according to any of claims 1-10, wherein the frame (1) is part of a base structure additionally comprising wheels (5) and wheel suspensions (4).
Apparatus according to claim 11, wherein the base structure is a trailer base structure additionally comprising a hitch (3).
Apparatus according to claim 11 or claim 12, wherein the wheel suspensions (4) comprise levers (26) articulated to the frame (1) to swivel about a horizontal axis (Y).
Apparatus according to any of claims 11-13, wherein the wheel suspensions (4) are adjustable.
Apparatus according to claim 14, wherein the wheel suspensions (4) are self-adjusting maintaining a predetermined contact pressure of the rubbing element (13) on the ground surface.
Apparatus according to any of claims 1-15, comprising a pressing unit acting on the rotating annular rubbing element (13) and maintaining a predetermined contact pressure of the rubbing element (13) on the ground surface.
Apparatus according to claim 16, wherein the pressing unit abuts against the frame (1).
Apparatus according to any of claims 1-17 comprising a camera (49) monitoring the inner of the rubbing element (13).
Apparatus according to any of claims 1-18, wherein the rotation axis (X) is oriented inclined to the ground surface, the arcuate rubbing zone (22) extending along a portion of between 65% and 95% of a closed annular configuration.
Apparatus according to any of claims 1-18, wherein the rotation axis (X) extends at least essentially perpendicular to the ground surface, the arcuate rubbing zone (22) having a closed annular configuration.