APARATUS FOR CUTTING FREE COVERS IN COATING, E.G. ASPHALT COATING

Abstract: An apparatus (2) for cutting free cover well curb in coating (4), for instance asphalt coating (10), comprising a basis part (16) pivotally fastened around a vertical centre axis in proportion to a support plate (4), which is adapted to be placed centred on a cover (6), a in proportion to the basis part (16) and said centre axis radial adjustably fastened bracket part (18), a in proportion to the bracket part level adjustably fastened support bracket (26) for a rotating cutting or mill unit (42), preferably driven by an internal combustion engine (38), and a turning motor (54) inserted between the basis part and the support plate. Hereby an apparatus is obtained, which by simple provisions is able to automatically cut free a cover well curb. The apparatus is just placed in the middle of the cover, whereafter the driving motor preferably in the shape of a combustion engine is started. By means of a turning motor the quick-rotating cutting or mill blade is turned round along the edge of the cover well curb, while the cutting or mill unit slowly is moved downwards, until the web curb is cut free from the coating.

Description: Apparatus for cutting free covers in coating, e . g . asphalt coating . The present invention relates to an apparatus for cutting free covers in coating, for instance asphalt coating. For replacement and/or level adjustment of covers, for instance manhole covers for sewer, district heating or the like, settled in concrete or asphalt coatings, a relative big and time-consuming manual effort for cutting free the cover from the well curb is normally required, which usually is done by means of pneumatic tools. The invention has for its purpose to provide an apparatus for cutting free cover well curb in coating, for instance asphalt coating, and of the type described in the introduc¬ tory part, and by which cutting free cover well curb in a simple manner may be carried out quickly and precisely without manual effort. The apparatus according to the invention is distinctive in the fact that it comprises of a basis part pivotally fastened around a vertical centre axis in proportion to a support plate, which is adapted to be placed centred on a cover, a - in proportion to the basis part and said centre axis - radial adjustably fastened bracket part, a - in proportion to the bracket part - level adjustably fastened support bracket for a rotating cutting or mill unit, preferably driven by an internal combustion engine, and a turning motor inserted between the basis part and the support plate. Hereby an apparatus is obtained, which by simple provisions is able to automatically to cut free a cover well curb. The apparatus is just placed in the middle of the cover, whereafter the driving motor preferably in the shape of a combustion engine is started. By means of a turning motor the quick-rotating cutting or mill blade is turned round along the edge of the cover well curb, while the cutting or mill unit slowly is moved downwards, until the well curb is cut free from the coating. Apparently, the apparatus is such provided, that the turning motor is made by an electric motor driven by one by the internal combustion engine driven generator, which via an electrical control system also is connected with a battery. Preferably the level adjustment of the cutting or mill unit at the apparatus according to the invention is such provided that the support bracket is fastened on vertical guiding rod members of the bracket part, and that hydraulic support cylinders are inserted between the bracket part and the support bracket, which cylinders being provided with hydraulic liquid from a liquid tank via a hand pump. And apparently y, an adjustment valve being adapted to control descending of the cutting or mill unit is inserted between the support cylinders and the liquid tank. The turning mechanism of the apparatus is in a simple and robust manner such provided that the support plate around a central bearing housing consists of a rim of gear wheel being drive-connected with the turning motor via a driving wheel, preferab¬ ly in form of a pinion, as the rim of gear wheel and pineon are surrounded by a roller chain. To secure optimum cutting free of the cover well curb the apparatus according to the invention may profitably be such provided that the blade of the cutting or mill unit is weakly inclined downwards and inwards in proportion to said vertical centre axis. To secure good contact between cover and support plate the apparatus may profitably be such provided that the support plate at its underside is provided with downwards projecting grasping members, being adapted to gear into recesses of a figured top side of the cover. For use at improvement of circular holes in a coating, for instance asphalt or concrete coating, the apparatus according to the invention may profitably be such provided that the support plate at its underside is provided with a friction coating, being adapted to prevent rotation of the support plate, when this is placed at a mainly smooth surface. The invention is further explained in the following with the drawing, in which: - Fig. 1 shows a side view - partly in section - of an embodiment for an apparatus according to the invention, fig. 2 shows how a circular cover well curb may be cut free by means of the apparatus according to the invention, and, fig. 3 shows, that the apparatus according to the invention also may be used for cutting free of rectangular cover well curbs. The cover cutting apparatus shown in fig. 1 comprises a support plate 4 intended to be placed centred on a cover 6, which is placed in a well curb 8 being anchored in the asphalt coating 10. The support plate 4 is at the top side provided with a bearing housing 12 for a central bearing pivot 14 of a basis part 16. A bracket part 18 with a vertical part 20 is fastened radially moveable at the top side of the basis part 16 between guide rails 22 consisting of angle iron, and which may squeeze the bracket part 18 into the wanted position towards the top side of the basis part 16. The vertical part 20 comprises guiding rod members 24, on which a support bracket 26 is level adjustably fastened by gliding rod members 28. Between the bracket part 18 and upper parts of the support bracket 26 hydraulic support cylinders 30 are in- serted, which are connected with a hydraulic liquid tank 32 via a hand pump 34, so that the support bracket 26 by means of the hand pump 34 may be lifted upwards at supply of hydraulic liquid to the support cylinders 30. Subsequently the support bracket 26 may be moved downwards at restoring of hydraulic liquid to the tank 32 via an adjustment valve 36, so that the support bracket 26 may be descended rather slowly in proportion to the basis part 16. At the support bracket 26 a complete combustion engine 38 is mounted, which via a N-belt drive 40 is drive connected with a cutting or mill unit 42 with a cutting or mill blade 44, which in proportion to the vertical centre axis of the apparatus is weakly inclined downwards and inwards. The cutting or mill blade 44 is partly surrounded by a cover 46 by which cooling water may be supplied to both sides of the blades 44 from a water container 48 via a supply pipe 50 and a ramification 52. The basis part 16 is provided with an electrical turning motor 54, which via a pineon 56 is connected with a rim of gear wheel 58 fastened outside the bearing housing 12 by means of a roller chain 60, which surrounds the rime of gear wheel 58 and driving wheel 56. The electrical turning motor 54 is provided with electricity from a generator 62 being driven directly from the combustion engine 38, and which via a electrical control system also is connected with a battery 64, which also may deliver starting current to an electrical starting motor for the combustion engine 38. The electrical control system of the apparatus furthermore comprises a control board 66, on which the number of re- volutions of the turning motor 54 among others may be adjusted. The cover cutting apparatus 2 comprises one from the basis part 16 pivoting support bow 68, being provided with an inclined brace 70, and which at the top is provided with lifting eye 72 for use at crane handling of the apparatus. The cover cutting apparatus according to the invention is operating in the following manner: As shown in fig. 1 the cover cutting apparatus 2 is for instance placed by means of a truck crane centred on the cover 4 and with the cutting or mill unit 42 in the shown po¬ sition the combustion engine 38 is started preferably via the control board 66 by an electrical starting motor. The adjustment valve 36 is so adjusted that reconduct of the hydraulic liquid from the support cylinders 30 will take about 4 minutes, that is so that the descending speed of the support bracket 26 is pre-adjusted correspondingly. The turning motor 54 is started and its number of revolutions are adjusted on the control board 66 to for instance about 10 revolutions per minute. Hereafter the quickly rotating cutting or mill blade 44 while the basis part 16 slowly is rotating around the support plate 4 - will make a groove (fig. 2) in the asphalt coating around the cover well curb 8 and loose this from the asphalt coating 10, so that the well curb 8 easily may be taken up, be changed or be replaced in a new correct level, as the described operation most often takes place in connection with renewal of the asphalt coating 10. As shown in fig. 3 the cover cutting apparatus 2 naturally also may be used for cutting free rectangular cover well curb 76, which subsequently may be replaced by circular cover well curb fitting the made cutting out. At suitable choice of cutting og mill blade the apparatus according to the invention may be used more generally for making circular cutting outs in other types of coatings, such as concrete or flag coatings. In principle it is possible to use same principle to make circular cutting outs in horizontal divisions in buildings - or even in steel decks. Finally it may be mentioned, that the support plate of the cutting apparatus may have the same dimension as the cover, as this in that case is removed, whereafter the support plate of the cutting apparatus is placed directly in the well curb opening.

Claims: CLAIMS: 1. Apparatus for cutting free cover well curb in coating, for instance asphalt coating, characterized in that it comprises of a basis part pivotally fastened around a vertical centre axis in proportion to a support plate, which is adapted to be placed centred on a cover, a - in proportion to the basis part and said centre axis - radial ad¬ justably fastened bracket part, a - in proportion to the bracket part - level adjustably fa- stened support bracket for a rotating cutting or mill unit, preferably driven by a internal combustion engine, and a turning motor inserted between the basis part and the support plate. 2. Apparatus according to claim 1, characterized in that the turning motor is made by an electric motor driven by one by the internal combustion engine driven ge- nerator, which via an electrical control system also is connected with a battery. 3. Apparatus according to claim ^characterized in that the support bracket is fastened on vertical guiding rod members of the bracket part, and that hydraulic support cylinders are inserted between the bracket part and the support bracket, which cylinders being provided with hydraulic liquid from a liquid tank via a hand pump. 4. Apparatus according to claim 3, characterized in that a regulator valve is inserted between the support cylinders and the liquid tank, which valve being adapted to control descending of the cutting or mill unit. 5. Apparatus according to claim 1, characterized in that the support plate around a central bearing housing consists of a rim of gear wheel being drive-connected with the turning motor via a driving wheel, preferably in form of a pinion, as the rim of gear wheel and pineon are surrounded by a roller chain. 6. Apparatus according to claim 1, characterized in that the blade of the cutting or mill unit is weakly inclined downwards/inwards in proportion to said vertical centre axis. 7. Apparatus according to claim 1, characterized in that the support plate at its underside is provided with downwards projecting grasping members, being adapted to gear into recesses of a figured top side of the cover. 8. Apparatus according to claim 1 and intended to improvement of circular holes in a coating, for instance asphalt or concrete coating, characterized in that the support plate at its underside is provided with a friction coating, being adapted to prevent rotation of the support plate, when this is placed at a mainly smooth surface.

Inventors: FRIEDMAN GERSHON, ZACCHO BO RAVNSBAEK, FRIEDMAN, GERSHON, ZACCHO, BO, RAVNSBAEK
Applicants: FRIEDMAN GERSHON, RAVNSBAEK ZACCHO BO, FRIEDMAN, GERSHON, ZACCHO, BO, RAVNSBAEK
Application year: 1993
Main classification: E01C23
IPC codes: B28D1, E01C23, E02D29