FR2497705A1 - INSTALLATION FOR RECTIFYING BRAKE LININGS BY ROTARY MACHINING - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS AN INSTALLATION FOR RECTIFYING BRAKE LININGS, BY ROTARY MACHINING INCLUDING A MOUNTING DEVICE 4 FOR THE LUG TO BE RECTIFIED 5, A ROTARY MACHINING DEVICE 7 DRIVEN BY A MOTOR, AND INCLUDING A ROTARY ARM 9 PROVIDED WITH ' A CUTTING TOOL 11, AS WELL AS A DEVICE 16 FOR SUCTING AND COLLECTING THE DUST AND CHIPS PRODUCED DURING THE MACHINING OF THE BRAKE LININGS IN THE VICINITY OF THE CUTTING TOOL. ACCORDING TO THE INVENTION, THE DUST SUCTION DEVICE 16 IS MOUNTED DIRECTLY ON THE MACHINING DEVICE 7 AND ROTATES WITH THE latter. IN THIS WAY, SUCTION PATH IS EXTREMELY SHORT AND FRICTION LOSS REDUCED. THE SUCTION POWER DEVELOPED IS THUS USED IN EXTREMELY EFFICIENT WAY TO SUCK OUT DUST AND MACHINING CHIPS.

Description

The present invention relates to a permanent installation

  Fitted to grind brake linings by rotary machining. To rectify the linings, drum brakes, machining devices are now being used.

  a rotary cutting tool, one can either mount this device

  machining directly on the axle and tightening it on the axle, which eliminates the run-out of the linings that have been exposed. by means of the rotary cutting tool (see, for example, German Patent No. 1,232,032), either disassembling the brake linings to be ground from the wheel and mounting them, by centering them, in a clamping device for machining them then to the desired diameter using the rotating cutting tool of the

  machining device which in this case is fixed.

  During this machining, it is necessary to suck

  chips and more dust that result from the operation.

  In particular, when it comes to brake linings containing asbestos, the fibrous dusts of asbestos resulting from

  machining are extremely harmful to health.

  German Patent Application No. 28 37 873 discloses a provision

  dust protection device for machining equipment

  rotary brake lining assembly, which is in the form of a bell intended to cap the machining apparatus

  rotating as a whole; this bell is connected to a

  suction system, for example, to a household vacuum cleaner

  sucks and filters chips and dust produced by the machine.

  ge. Due to the large volume of the bell and the fact that it is impossible to close the bell hermetically with respect to the machining apparatus, this protective device requires high suction powers, when actually wants to eliminate all the dust and chips produced by machining. It has also been attempted to provide a suction duct opening only in the vicinity of the cutting tool, and moved along the machining device while being connected by slip rings to a fixed vacuum cleaner. However, this arrangement has a drawback which lies in the fact that the paths

  are relatively long so that a large part of the

  of the suction power is dissipated by the losses

  resulting from friction. In addition, the power still remains

  clouded by slip rings, Accordingly, a te. dis-

  Positive suction also requires high suction power. It can be seen that in order to be able to work with the two above-mentioned installations practically dust-free, it is necessary to have dust collection equipment that is so large and expensive that

  these facilities can no longer be economically viable.

  There is therefore a need for low power installations

  nevertheless, they are sufficiently effective to enable them to obtain

  the desired removal of dust during machining.

  Accordingly, it is an object of the present invention to provide a grinding installation of the specified type

  above, provided with a suction device having a power

  high suction efficiency combined with short trips

  and small volumes of suction.

  These goals are achieved by the installation of rectifications according to the invention that is characterized er. that its suction device is mounted directly on the rotary machining device to be able to rotate with it. Under these conditions, the aspiratinr device may be mounted so as to form a counterweight either for the rotating arm of the machining device or for a motor possibly provided on the machining device.

  Because the suction device is mounted directly

  on the machining device, the suction paths of the

  come very short, so that the suction power developed is not likely to be diminished by significant friction losses. In addition, dust and chips, which are produced during machining, can be sucked into the immediate vicinity of the cutting tool, which greatly reduces the

  volume sucked. In these circumstances, virtually all

  developed suction is used.

  Other features and advantages of the invention

  will emerge from the description which follows, made only

  by way of non-limiting example, with reference to the attached drawings in which:

  FIG. 1 is a schematic view, partially in section

  For example, an installation can correct the brake linings.

  equipped with a suction device according to the invention.

  FIG. 2 is a diagrammatic front view of the installation

  tion of Figure 1; Figure 3 is a side view, partly in section, of a dust suction device according to a second embodiment of the invention; Figure 4 is a schematic view, partly in section of a dust suction device according to a third embodiment of the invention; and, Figure 5 is a schematic view, partially in

  section, of another suction device according to the invention.

  The installation I for grinding the brake linings, which is the subject of the present invention, comprises a tubular support 2 mounted, by means of shims 3, on the rocket 4 of an axle which carries a brake lining 5 of a truck, for example, and secured to this axle stub axle

by means of a clamping ring 6.

  Around the tubular support 2, is mounted a rotary machining device 7 which can be rotated in a conventional manner around the support 2, with the aid of a motor 8,

  and a non-represented chain transmission.

  The machining device further comprises a radial arm 9

  on which is mounted a tool holder 10 parallel to the axis of rotation

  tation. At the front end of the tool holder, facing the brake lining 5, is fixed a cutting tool 11 having a cutting tip 12. The spacing between the cutting tip 12 and the axis of rotation of the device can to be modified as necessary, by means of an adjustment mechanism, not shown, for adjusting the depth of cut. The tool holder 10 is hollow and is formed so as to have an open channel 13 whose suction port 14 is located in the immediate vicinity

cutting edge.

  On the rear end of the tool holder 10, is threaded a

  flexible or rigid connecting pipe 15 which results in a device

  suction line 16, also attached to the machining device.

  This suction device may have different

  different forms of realization; in Figure 1, it is constructed in the form of a domestic vacuum cleaner. This vacuum cleaner comprises a cylindrical envelope 17 whose axis is parallel to the axis of rotation of the machining device and which is closed, on the side on

  which the connecting pipe 15 opens, by a cover 18.

  The pipe 15 passes through this cover and is attached thereto in a suitable manner. Inside the casing 17, there is firstly a paper filter bag 19 intended to retain the large chips sucked during the machining of the brake linings and which is followed by a second filter bag 20, also made of paper for to stop the relatively fine dust. These filter bags are retained in the casing 17, conventionally, using elastic rings 21 or similar means. After the second filter bag 20 is morntee inside the casing a turbine 22 which is driven in rotation by a

  rapid electric motor 23, the motor 23 is fixed in the

Veloppe 17 by means of flanges 24.

  On the side opposite to the brake lining to be rotated, the machining device 7 carries a sleeve 25 which surrounds the tubular support, extends beyond it and rotates with the device 7. The end of the sleeve 25 is surrounded by an annular support 26 in which are embedded three rings

collectors 27.

  The support 26 of the slip rings also rotates with the machining device. The bottom of the sleeve 25 is crossed by a

  threaded spindle 28 which is connected to the bottom of the tubular support 2.

  The threaded spindle 28 carries an adjusting nut 29 which bears on the bottom of the mandrel 25. On the edges of the adjusting nut 29 which is fixed, is formed a cover 30 covering the support of the

  slip rings. In this lid, opens a drawstring

  3, each of which is connected to a contact 32 sliding on one of the slip rings. On the

  power cord, is mounted, conventionally an inter-

  The three slip rings are each connected, by unrepresented conductors, to the motor 8 driving the machining device and to the electric motor 23 of the device.

  suction 16, these two devices are thus connected in parallel.

  In this way, a simple safety relay provided for in the in-

  This switch prevents one of the motors from being

  without the other. We have the assuzance that during the machining -

  brake linings, the suction device is opera-

tioning.

  To machine the brake linings, we first set the

  desired cutter of the cutting tool, then rectify

  brake linings. During this rectification, the

  positive machining 7 is moved axially, in the direction of the arrow P, until the entire width of the brake lining has been rectified. The chips and the dust resulting from the machining are sucked into the orifice 14 and gain through the channel 13 of the tool holder and through the connecting pipe 15,

  the suction device 16 o they are separated from the air as-

  drawn by the filter bags 19, 20.

  Figures 3 to 5 illustrate different modes of

  suction device. The same components or com-

  equivalent to those of the embodiment of Figures I and 2 have been designated by the same reference numerals, to which has been added an index corresponding to the number of

the figure.

  In Figure 3, we see a suction device 163

  forming an integrated assembly or unit with the engine 83.

  In place of the usual ventilation wheel, a motor turbine wheel 83 has been mounted on the motor shaft 83. The motor casing has been lengthened accordingly; in this extension, as in FIG. 1, a roughing filter bag 193 and a fine filtering bag 3 have been fixed. The envelope is closed by a cover 183 and is connected by a connecting pipe 153.

  to the tool holder, as in Figure 1.

  In FIG. 4, the ventilation wheel of the motor 84 has also been replaced by a fast turbine wheel 224. In FIG.

  a separate envelope 174, which is also connected to the

  machining center, are housed, as has been described with reference to Figure 1, an anterior filter 194 and a posterior filter 204. The envelope of the motor 8 enclosing the turbine wheel 224 is connected to the envelope 174 containing the filters, through a connecting pipe 34. The casing 174 carries a second connecting pipe 154 leading to the tool holder, as shown in FIG.

figure 1.

  In Fig. 5, the motor 85 is unchanged; the only

  difference is that his tree comes out of the envelope.

  The suction device 165 simply comprises a casing 17 enclosing the filters 195 and 205 which follow a wheel

  turbine 22 whose shaft is also to enter the

  develops. The motor shaft and that of the impeller wheel are connected by a suitable transmission member, i'curence, by a toothed belt 35, so that the turbine wheel is driven directly by the engine. The envelc-ppe 175 suction device 16. is connected, count in the figure !, by a pipe 15, the hollow tool holder, the embodiments of the fI ure 3 to 5 require only one only electric motor serving both to drive the machining device and the suction device. In these

  conditions, these two devices can only be ac-

  jointing. For greater safety, protection:

  charges may be provided to ensure the shutdown of both devices, for example, when the filters are full.

  In the figures The suction device has been

  te as being installed in a straight cylindrical tube.

  However, it goes without saying that it is also possible to adopt envelopes having other forms, for example, circular envelopes which surround, at least partially, the machining device. The paper filters can, without difficulty, be

  housed in these circular envelopes.

  It will be appreciated that the invention provides a device for

  for a machining apparatus which, because it is mounted on it, has only short breathing paths and thus has only low friction losses. As a result,

  suction power that can be achieved with such

  is much higher than that obtained with

  traditionnal suction line. In addition, its handling and use are more flexible and its clutter is weak,

  made of the compact construction mode of the machining apparatus.

  An aspiracion device according to the invention can also be used on obile machining devices, such as those described with regard to the various figures, or on fixed machining devices.

Claims (10)

  1. Installation for grinding brake linings, by rotary machining, which comprises a mounting device for the brake linings to be ground, a device   motor-driven rotary machining machine, which carries an arm   seen from a cutting tool, as well as a suction device from the   dust and chips produced in the vicinity of the cutting tool   during the machining of the packing, characterized in that the suction device (16) is mounted directly on   the machining device (7) and rotates with it.   2. Installation according to claim 1, characterized in that the suction device (16) is connected to a conduit   suction nozzle (15, 13) having a suction port (14)   killed in the immediate vicinity of the cutting tool (11). S   3. Installation according to claim 1 or 2, characterized   in that the motor (8) driving the machining device   ge (7) is rotatably mounted therewith.   4. Installation according to any one of the claims   1 to 3, characterized in that the suction device (16)   is constructed in the form of a household vacuum cleaner   one or more filters (19, 20).   5. Installation according to any one of the claims   1 to 4, characterized in that the suction device (16) comprises its own motor (23) provided with a turbine wheel (22) for sucking up the dust and chips produced during   machining in the immediate vicinity of the cutting tool (11).   6. Installation according to claim 3, characterized   in that the motor (83) is a fast motor on the shaft   which is mounted a turbine wheel (223) to suck up the push-   and chips resulting from machining.   7. Installation according to claim 6, characterized in that in the motor casing (8 3) and the turbine wheel   (223) are provided filters (1939 203) to separate the push- sieved chips.   8. Installation according to claim 6, characterized in that the end of the casing of the motor (84) facing the turbine wheel (22 4) is connected by a pipe (34) to a casing (174) containing one or more filters (194, 2014) and, in that the inlet of the casing (174) is connected to a connecting pipe (154) for drawing dust and chips produced during machining.   9. Installation according to claim 3 or 4, characterized   characterized in that the motor (85) drives, via a transmission member (toothed belt 35) the turbine wheel   (225) of the suction device (165).   10. Installation according to any one of the claims   1 to 9, characterized in that the suction device (16) is   mounted on the machining device (7) so as to form the   the weight of the arm (9) and the motor of the device.