Patent Application
20110000354
The present invention relates to a cut-off machine for rails or the like.
Document FR 2 267 418 describes a cut-off machine for rails or the like, comprising a drive unit driving, via a belt, a cutting disk fixed to a disk holder, a sleeve of axis parallel to the axis of the cutting disk, intended to be fixed to a support and guidance device for supporting and guiding the cut-off machine and comprising a vise for attachment to the rail and allowing the cut-off machine to pivot in the plane of the cutting disk.
A first disadvantage with this type of cut-off machine lies in the fact that it is unable to make cuts perpendicular to the rail with a satisfactory quality of cut.
This is because the vibrations caused by the motor and the stresses applied by the user to the cut-off machine are transmitted directly to the cutting disk, which means that the cutting disk cannot be kept in a plane perpendicular to the rail and a satisfactory quality of cut cannot therefore be obtained.
A second disadvantage with this type of cut-off machine is that the vibrations generated by the motor and transmitted to the cutting disk lead to rapid disk wear. Thus, cutting disk life is very short, entailing regular replacement of cutting disks. This rapid wearing of the cutting disk greatly increases the cost and the length of the cutting operation.
A third disadvantage with this type of cut-off machine lies in the fact that significant vibration generated by the motor and the cutting disk is transmitted to the user during the cutting operation, this being something that is highly prejudicial to user comfort and safety.
The present invention aims to remedy these disadvantages.
The technical problem addressed by the invention is therefore that of providing a cut-off machine able to improve the quality of cut of the rails, and to reduce the rate of wear of the cutting disk while at the same time improving user comfort and safety.
To this end, the present invention relates to a cut-off machine for rails or the like, of the type described hereinabove, wherein the sleeve and the disk holder form a one-piece assembly mounted on the drive unit with the interposition of elastic means.
Creating a one-piece assembly comprising the sleeve intended to be fixed to a device for supporting and guiding the cut-off machine and the disk holder allows the cutting disk to be kept firmly in a determined plane when the sleeve is fixed to a device for supporting and guiding the cut-off machine. This makes it possible to limit the vibrations generated by the cutting disk and therefore to obtain an improved quality of cut and to reduce the rate of wear of the cutting disk.
In addition, the elastic means are designed to deform elastically when stresses are applied to the cut-off machine by the user or when vibrations are generated by the motor so that these stresses and vibrations are not transmitted to the cutting disk.
Thus, the presence of these elastic means further improves the quality of cut of the cut-off machine.
Further, the presence of these elastic means makes it possible to avoid transmitting to the operator the vibrations generated by the cutting disk and therefore improves user comfort and safety.
Advantageously, the one-piece assembly comprises a mounting plate bearing the sleeve and a bearing for mounting a cutting disk driveshaft.
As a preference, the cutting disk driveshaft projects on each side of the bearing, a drive pulley collaborating with the belt of the drive unit being fixed to a first end of the driveshaft and a disk attachment device being fixed to the other end of the driveshaft.
Advantageously, the elastic means have lower elasticity in the direction in which the belt is tensioned than they do in the other directions. This feature makes it possible to avoid too great a reduction in the inter-axis distance between the axes of the motor pulley and of the cutting disk drive pulley. As a result, the motor belt can be kept under enough tension that it can drive the disk drive pulley.
As a preference, the elastic means comprise at least one elastic element, such as a block or a sheet, positioned between the drive unit and the mounting plate of the one-piece assembly. It should be noted that the elastic elements may be blocks which may adopt various shapes and/or cross sections along their length, it being possible for example for the blocks to be cylindrical, frustoconical, parallelepipedal, or diabolo-shaped. The blocks or sheets may be made of natural or synthetic rubber or any other synthetic material.
According to yet another feature of the invention, the drive unit comprises a first part containing the motor of the cut-off machine and a second part on which the one-piece assembly is mounted, the second part being movable with respect to the first part so as to allow the cutting disk drive belt to be tensioned sufficiently, locking means being provided for locking the relative position of the first and second parts.
Advantageously, the cut-off machine comprises at least one elastic element running at right angles to the plane of the cutting disk, the elastic element being positioned between the second part of the drive unit and the mounting plate of the one-piece assembly.
As a preference, the cut-off machine comprises at least one elastic element running parallel to the plane of the cutting disk, the elastic element being positioned between the second part of the drive unit and the mounting plate of the one-piece assembly.
According to another feature of the invention, each elastic element running at right angles to the plane of the cutting disk has greater elasticity than each elastic element running parallel to the plane of the cutting disk.
According to yet another feature of the invention, a protective disk guard is fixed to the mounting plate.
In any event, the invention will be clearly understood with the aid of the description which follows, with reference to the annotated schematic drawing which, by way of nonlimiting example, depicts one embodiment of this cut-off machine.
The cut-off machine 2 further comprises a sleeve 8 of axis parallel to the axis of the cutting disk 6, intended to be fixed to a support and guidance device 26 for supporting and guiding the cut-off machine and comprising a vise for attachment to the rail and allowing the cut-off machine to pivot in the plane of the cutting disk and at right angles to the rail to be cut.
The sleeve 8 and the disk holder 7 form a one-piece assembly 9. As shown more particularly in
As shown in
The one-piece assembly 9 is mounted on the drive unit 3 with the interposition of elastic means.
The elastic means comprise several substantially cylindrical elastic blocks 14, 15 positioned between the drive unit 3 and the mounting plate 10 of the one-piece assembly 9.
The drive unit 3 comprises a first part 16 containing the motor of the cut-off machine and a second part in the form of a plate 17 on which the one-piece assembly 9 is mounted to the side. The second part 17 is movable with respect to the first part 16 so as to allow the cutting disk drive belt 5 to be tensioned sufficiently. Locking means are provided for locking the relative position of the first and second parts. These locking means comprise screw/nut fixing systems 18 intended to slide in oblong holes 19 formed in the second part 17 of the drive unit, the holes running in the direction in which the belt 5 is tensioned.
As shown in
It should be noted that the elastic blocks 14 have greater elasticity than the elastic blocks 15 so as to avoid an excessive reduction in the inter-axis distance between the axes of the motor pulley and of the drive pulley 12 during cutting, as such an excessive reduction could result in insufficient tensioning of the disk drive belt 5.
Each elastic block 14 is made up of a cylindrical central part 141 made of natural rubber and of two cylindrical and metallic end parts 142. Each end part has a tapped axial hole 18 opening onto an end face of the block.
Each block 14 is fixed between the mounting plate 10 and the second part 17 of the drive unit 3 via two fixing screws 19, the threaded shank of which passes through a respective opening 21, 22 formed in the mounting plate or in the second part 17 of the drive unit and collaborates with the tapped axial hole in the corresponding end part of the block, and the head of which forms an end stop and collaborates with, respectively, the exterior wall of the mounting plate 10 or of the second part 17.
Each elastic block 15 is made up of a cylindrical part made of natural rubber and of a threaded axial shank fixed to one of the end faces of the cylindrical part of the block.
Each block 15 is fixed between the mounting plate 10 and the second part 17 of the drive unit 3 by inserting the threaded shank of the block 15 into an opening made in the leg of an angle bracket 23 fixed to the interior wall of the second part 17 of the drive unit, a nut 24 being screwed onto the threaded shank of the block in such a way as to fix the block 15 to the angle bracket 23. Another angle bracket 25 is fixed to the interior wall of the mounting plate 10 in such a way as to rest against the opposite face of the block to the nut.
Further, the cut-off machine comprises, as shown in
As goes without saying, the invention is not restricted only to that embodiment of this rail cut-off machine that is being described hereinabove by way of example but encompasses all variant embodiments thereof. Thus, in particular, the elastic means could consist of springs, hydraulic or gas cylinders, or be made of viscoelastic material.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0611453 | Dec 2006 | FR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/FR2007/002046 | 12/12/2007 | WO | 00 | 9/15/2010 |
