GB2093893A - Road surface cutting machines - Google Patents

Abstract

In a cold-working road surface planing machine a down-cut rotary cutter 7 receives a superimposed vibratory impacting action, as from vibrator 15, to avoid the need for heaviness. As shown the vibratory cutter assembly 7-26-15 carries depth-of-cut adjusting wheels 12 and is pivotably mounted about transverse and longitudinal axes 8, 10 on a power driven wheeled chassis carrying a spray or ballast tank 4 and a drive means 3. In a modification dispensing with the vibrator 15 a rotary cutter assembly is pivotably mounted in a pair of side plates removably bolted to a conventional vibrating roller. <IMAGE>

Description

SPECIFICATION Road surface cutting machines The invention relates to a method for removing layers of bitumen, concrete or the like, particularly from road surfaces.

It is known to initially heat the road surface by means of gas burners or the like and then remove the warmed-up road surface layer using cutters if such removal is required for purposes of road surface repair, for levelling a road construction site with respect to the intact road surface, also for cutting grooves into a road surface as well as for removing braking beads formed in the road surface at traffic lights.

It is also known to operate large area cutters as cold cutters, such cold cutters requiring high operating weight to ensure that the cutter sinks in sufficiently deep. Application of large masses to create such weight may cause severe disadvantages and regularly requires special vehicles for moving such cutters.

The present invention overcomes the abovementioned and the other shortcomings of the prior art by a novel and improved mode of the cutting operation. The method of the invention neither requires the action of heat nor the utilization of large masses of weight to ensure sufficient depth of the cut.

In its broadest aspect the invention provides for superimposing an impact motion over the cutting motion. By superimposing said two different motions, i.e. practically static rotary motion of the cutter and the additional application of the impact motion practically representing a dynamic motion, at low operational weight cutting depths are achieved which do not anymore require heating or the application of high masses of weight. The use of the method according to the invention is particularly advantageous in removing concrete surface layers since removal thereof in the prior art is regularly possible only by using very large masses of weight.

In further development the method according to the invention provides for the impacting motion to be derived from a vibratory motion known per se. Thereby the invention enables the desired motion to be derived from apparatus like for example vibratory compactors, vibratory rollers or the like regularly present at construction sites anyway.

For carrying out the aforementioned method according to the invention an apparatus including a cutting roller adapted for being driven is provided and characterized by the cutting roller being equipped with means for generating an impact motion. The impact motion is understood particularly to represent periodically changing movements like oscillatory movements, vibratory movements, shaking movements or the like.

The apparatus according to the invention may be designed as a trailer, as a semi-trailer or as a self-propelled unit.

In a particularly convenient design of the apparatus according to the invention drive means are associated with the cutting roller through a driving roller, drive wheels or the like in a common frame.

In further development the apparatus according to the invention provides for the means for generating the impact motion to be disposed within the interior of the cutting roller and/or of the driving roller. By such a design a distinctly compact structure of the whole apparatus is achieved particularly facilitating the storage and transfer thereof.

In accordance with the invention it may also be provided that the means for generating the impacting or vibratory motion are placed outside of the cutting roller at the journalling frame thereof. This may be particularly convenient for very small apparatus, i.e. apparatus having small widths of operation.

A feature essential for the apparatus according to the invention in further development thereof resides in that the cutting roller is arranged at connecting elements adapted to be rigidly connected to known vibratory rollers. With such a design the apparatus according to the invention includes an accessory unit which may be connected to known, for example manually operated vibratory rollers by means of the aforementioned supporting elements with just a few hand operations thus converting the vibratory roller into a high efficiency cutting roller. In this way the motion generated by the vibratory roller may be employed immediately to generate the impacting motion of the cutting roller.

Therefore, it is a general object of the present invention to provide a novel and improved road surface cutting method and apparatus for carrying out the same.

It is another object to be achieved by the present invention to provide for a road surface cutting method and apparatus for carrying out the same which achieve sufficient cutting depth without requiring warming of the road surface layer prior to the cutting operation.

It is a further object to be achieved by the present invention to provide for a road surface cutting method and apparatus for carrying out the same which achieve sufficient cutting depth without requiring additional weight loads to be applied during the cutting operation.

It is still another object of the invention to design a road surface layer cutting apparatus of distinctly compact structure.

It is a further object to be achieved by the invention to provide for a road surface layer cutting apparatus designed to be readily coupled as an accessory unit to vibratory road construction apparatus.

Other and further objects, features and advantages of the present invention will be readily apparent to those skilled in the art when the following description of the preferred embodiments is read in conjunction with the accompanying drawings.

Fig. 1 is a simplified side view of an embodiment of the apparatus according to the invention comprising a driving roller and a cutting roller, and Fig. 2 shows a modified embodiment of the apparatus as illustrated in Fig. 1 in a similar mode of illustration, said modified embodiment including an accessory unit to a duplex vibratory roller.

With reference to the drawing of fig. 1 a preferred embodiment of an independent type of cutting apparatus in accordance with the invention will be described. The apparatus illustrated in fig. 1 in a side view and generally designated by 1 comprises a supporting and vibrating frame 2 supporting conventional drive means 3 not illustrated in detail and a tank 4 holding spray water or ballast water. Drive means 3 are designed to drive either a driving roller or drive wheels 5 which are not differentiated in the side view of fig. 1. The movement of the entire apparatus is guided and controlled by means of a conventional guiding and control rod 6 requiring no detailed explanation.

A cutting roller 7 is driven by the drive means 3, too; the cutting roller 7 is pivotably journalled in the supporting frame 2 for pivoting movement about a first pivot axis 8 extending substantially normally with respect to the general direction of the cutting operation as indicated by the doubleheaded arrow 9 and about a second pivot axis 1 0 extending in the direction of the double-headed arrow 9. The amplitude of the pivoting movement of the cutting roller 7, i.e. the adjustment of the cutting depth in the direction of the doubleheaded arrow 11, is effected by the height adjustment of supporting wheels 12 by means of a hand crank mechanism 13 or any other mechanism suitable therefor.No further illustration is given relating to pivoting of the cutting roller 7 about the second pivot axis 10 by means of which the cutting roller 7 is tilted relative to a plane extending in parallel to the working plane 1 4 to cut grooves or channels, such pivoting means being known to persons skilled in the art.

An impacting tool 1 5 is indicated by dashed lines in fig. 1, the impacts generated thereby being enforced on a supporting subframe 26 for the cutting roller 7.

The means for generating the periodically changing movements of the cutting roller 7, also, may be located within the interior of driving roller 5, the vibratory movements thereof, then, being transferred to the cutting roller 7 immediately via the frame 2 since the cutting roller 7 is force lockingly coupled thereto.

A modified preferred embodiment including the cutting apparatus in accordance with the invention as an accessory unit is shown in fig. 2 in a view essentially similar to that of fig. 1.

A conventional duplex vibratory roller designated generaily by 16 has a drive unit 17, a spray water or ballast water tank 18 and two rollers 20 journalled in a common vibrating frame 19. A supporting fork 21 for a cutting roller 7' is rigidly, i.e force- and form-lockingly connected thereto, for example by means of six screws 23.

Other available connecting means may be utilized therefor as long as such connecting means ensure that the vibrations generated by the vibratory rollers are transferred to the supporting fork 21.

The vibrations which for example may be generated in the usual manner by an exciter not shown in detail and located within the roller 20 and which are transferred to the frame 1 9 are transferred through said frame to the cutting roller 7' due to the rigid connection of the same thereto through supporting fork 21.

In the supporting fork 21 a support bearing 26' for the cutting roller 7' is journalled for pivoting upwardly and downwardly about a first pivot axis 8' extending normally with respect to the general direction of the cutting operation as indicated by the double-headed arrow 9, said support bearing as such being arranged for rotation about a second axis 1 0' in the general direction of the cutting operation. As described with reference to fig. 1, different angles of inclination are thus adjustable for the cutting roller 7' in accordance with respective application requirements.

The cutting depth is designated by "x" in fig. 2 and different cutting depths may be adjusted by means of mechanical, hydraulical or other known and readily available adjusting elements. In the embodiment as shown in fig. 2 one manually operated adjusting screw 22 will be recognized; actually two such screws are provided, one on each side of drive means 3'.

The apparatus as described hereinbefore operates as follows: If a cutting roller is required at a road construction site, the operator of the vibratdry roller may connect the accessory cutting roller unit to the vibratory roller on site by very simple means, namely by the screws 23. The cutting roller 7' is, then, adjusted with respect to the desired cutting depth as well as with respect to the angle of inclination relative to the working plane 1 4 by respective adjustment of the adjusting screws 22, i.e. by pivoting about the first pivot axis 8'. The duplex vibratory roller is advanced with simultaneous operation of the cutting roller 7' by starting drive means 3' so that the vibratory motion of the vibratory roller 1 6 becomes superimposed over the mere cutting motion of the rotating cutting roller 7'. Thereby, the operating weight of the entire apparatus may be maintained very small even at great cutting depths "x".

By means of the modified embodiment as shown in fig. 2 vibratory rollers already present may be converted to highly efficient cutters by applying simple means.

The mode of operation of the independent apparatus as described hereinbefore with reference to fig. 1 is the same as described above in respect of the fig. 2 embodiment. This mode of operation does not depend on whether the impacting tool is present as an external impacting tool 1 5 or as an integrated vibrating drive in the drive unit.

In the embodiments of the invention as described hereinbefore a particular advantage is achieved by conducting the cutting motion in phase with the advancing motion, i.e. by designing the cutting roller as an in-phase operating roller. In the prior art the cutting rollers are operated in an anti-phase fashion so that the cut-out matter is at least partially thrown up on the surface to be worked in front of the cutter whereby the operator may become unable to accurately recognize the cutting edge. By the design of the apparatus in accordance with the invention inter alia this significant disadvantage is avoided since the inphase run of the cutter causes the cut-out matter to be conveyed rearwardly thereof without making the cutting edge unrecognizable.The dynamics of the system enable in-phase operation of the cutters for the first time whereby inter alia a substantial saving in the required driving power is achieved.

Naturally, the embodiments may become modified in many respects without changing the basic idea of the invention In particular, the invention is not restricted to small cutting rollers, i.e. rollers of small operating width. The principle of the invention is independent of unit size. Also, the invention is not restricted to the specific kind of adjusting means for adjusting the cutting depth and/or the cutting angle as described hereinbefore.

Thus the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While preferred embodiments of the invention have been described for the purpose of this disclosure, numerous changes in the construction and arrangement of parts can be made by those skilled in the art, which changes are encompassed within the spirit of this invention as defined by the appended claims.

Claims (15)

1. Method for removing a surface layer of bitumen, concrete or the like particularly from a road surface in which method the surface layer is removed by cutting said surface layer and by superimposing an impacting action over the cutting action.

2. Method as claimed in Claim 1 wherein the impacting action is derived from a vibratory action.

3. Method as claimed in Claim 1 or Claim 2 wherein the cutting and impacting action is performed by means of a cutting roller associated with drive means including a driver roller or drive wheels, said cutting roller being advanced to run in-phase with said driving roller or drive wheels.

4. Apparatus for removing a surface layer of bitumen, concrete or the like particularly from a road surface, said apparatus including a cutting roller and means for driving the same and comprising means for generating an impacting action associated with said cutting roller.

5. Apparatus as claimed in Claim 4 wherein the cutting roller is mounted in a support forming a subframe adapted to be connected to a main frame to which the drive means are mounted.

6. Apparatus as claimed in Claim 5 wherein the main frame forms a common frame supporting the subframe including the cutting roller and the drive means including the driving roller or drive wheels.

7. Apparatus as claimed in Claim 6 wherein the impact generating means are disposed within the interior of the cutting roller and/or driving roller.

8. Apparatus as claimed in Claim 6 wherein the impact generating means are arranged to act upon the subframe supporting the cutting roller externally of said cutting roller.

9. Apparatus as claimed in Claim 6 wherein the cutting roller is pivotably journalled in the subframe for pivotation about two pivot axes permitting adjustment with respect to the cutting depth and with respect to the cutting angle.

10. Apparatus as claimed in Claim 9 wherein mechanically operated and/or fluid operated adjusting means are provided to adjust the cutting roller to the respectively desired cutting depth and to the respectively desired cutting angle.

11. Apparatus as claimed in Claim 5 wherein the subframe is adapted to be rigidly, but releasably connected to the main frame of a vibratory roller.

12. Apparatus as claimed in Claim 11 wherein the impact generating means are provided by the vibratory roller.

13. Apparatus as claimed in Claim 11 wherein the cutting roller is pivotably journalled in the subframe for pivotation about two pivot axes permitting adjustment with respect to the cutting depth and with respect to the cutting angle.

14. Apparatus as claimed in Claim 13 wherein mechanically operated and/or fluid operated adjusting means are provided to adjust the cutting roller for the respectively desired cutting depth and for the respectively desired cutting angle.

15. Apparatus as claimed in any one of Claims 4 to 14 wherein the cutting roller is adapted to be driven in-phase with respect to the driving roller.

associated therewith.

1 6. A method substantially as hereinbefore described.

1 7. Apparatus constructed and arranged substantially as hereinbefore described and as shown in Figure 1 of the accompanying drawings.

1 8. Apparatus constructed and arranged substantially as hereinbefore described and as shown in Figure 2 of the accompanying drawings.