EP0083518A1 - Deep slitting machine for making grooved wheels for air tyres from non plane blanks - Google Patents

Abstract

Machine for slitting deep in the periphery of non-planar discs intended for obtaining tires with pneumatic tires, in which the splitting disc 3 is rotated on a floating support, that is to say automatically compensates for irregularities flatness while the slitting wheel (s) 4 are mounted on a drive device rigidly supported on a fixed frame.

Description

When it is desired to obtain, by deep splitting or slitting of the periphery of non-planar discs, wings of the same thickness or of different thickness so as to then conform these wings in order finally to obtain vehicle wheels each provided with a pneumatic tire, we quickly realize that deep splitting is very difficult if not impossible due to deformations of the flatness of the disc and internal tensions inherent in the material of the disc. In addition, the disc undergoes before the deep splitting of the deformations because the central web of the wheel is stamped in order to place the hub forming the wheel support and also to give this web of desired shapes in order to create, for example, a wheel of style.

There are machines which allow relatively deep splitting by exerting on the two side walls of the disc very high pressures forcing the area during splitting to be practically flat, but these machines are complicated and expensive because they require considerable power.

The present invention overcomes these drawbacks by creating a machine on which the slitting disc is rotated on a rigid support but in which the slitting wheels are mounted on a drive device which can move angularly on a frame designed for this purpose. function.

According to the invention, it is also planned to make a machine on which the slitting disc is rotated on a floating support, that is to say compen automatically flatness irregularities while the slitting wheel (s) are mounted on a drive device rigidly supported on a fixed frame. It is also possible to make a machine by providing the mounting of the slitting disc on a floating rotary support and the slitting wheel (s) also being mounted on a drive device which can move as necessary on a floating frame designed for this purpose. function.

According to the invention, the machine is constituted by a rigid frame on which are mounted two ends of shafts driven in rotation in synchronism, these two ends of shafts carrying the disc or blank to be split deeply on its periphery then the aforementioned frame carries at least one U-shaped support articulated on an axis, this floating assembly being subjected to the action of a motor member making it possible to follow the deformations of the disc in order to allow at least one splitting wheel rotating on a shaft driven imperatively d '' nick and deeply cut the periphery of the disc.

According to another characteristic of the invention, the splitting wheels are mounted on fixed drive members but the slitting disc is mounted on a drive device which can move angularly, that is to say floating.

According to another variant of the invention, the machine can also include a floating mounting of the slitting disc allowing the angular displacement of the latter and also a device which can be angularly moved, that is to say floating for the slitting wheel (s) .

According to another feature of the invention, the slitting wheel (s) have a thickness "E" equal to seven or ten times the thickness "e" of the disc to be slit, the diameter "d" of the wheel (s) is between 30 to 70% of the outside diameter "D" of the disc, the identical angle "A" of each wheel is greater than 60 ° and can range up to 90 °, the peripheral end of each wheel is slightly obtuse and not cutting and during the working phase for deep slitting the working area of the wheel or wheels is permanently in an oil bath to prevent seizure of the or the knurls and also avoid the removal of metal molecules from the disc.

Various other characteristics of the invention will also emerge from the detailed description which follows.

Embodiments of the object of the invention are shown, by way of examples, in the accompanying drawings.

Fig. 1 is a schematic elevation, partly in section, of a first embodiment of the machine in which the slitting wheel (s) are mounted floating to compensate for the deformations and internal tensions of the disc to be slit.

Fig. 2 is a schematic elevation, partly in section, showing the machine in which the disc is mounted on a floating rotary support while the slitting wheel (s) are mounted on a fixed frame.

Fig. 3 is a schematic elevation of a third embodiment of the machine in which the slitting disc is mounted on a floating rotary drive device as well as the slitting wheel (s) whose support comprises a so-called floating suspension device .

Fig. 4 is a schematic side elevation corresponding laying in fig. 3.

Fig. 5 shows a cross-elevation of a disc during deep slitting and, in external view, one of the slitting rollers used on the machine.

In fig. 1, there is shown schematically the working area of a disc slitting machine, this machine generally being of the "lathe" type. The two ends of shafts 1, 2 are mounted on the ends of the lathe. As a result, these ends of the shaft can rotate at a predetermined speed in the direction of the arrows F1, F2 (fig. 1). These shafts 1 and 2 thus rigidly hold the disc 3, the periphery 3a of which is to be slit deeply using at least one knurling wheel 4 which is mounted on a shaft 5 which is necessarily driven in rotation, this shaft 5 being mounted in bearings integral with a support 6 in "U" fixed on axes 6a integral with the bench of the lathe so as to be able to move angularly along the arrows F3, F4 (fig. 4). In fact, this support 6 in "U" shape is placed under the control of a double-acting cylinder 7, the rod 8 of which carries at its end 8a a ball stop 9 integral with the lower part of the support 6 in "U" shape. The supply to the double-acting cylinder 7 is effected by means of an electronic feeler 10 acting on the supply drawers of the double-acting cylinder 7.

The above description shows the use of a double-acting cylinder 7 of the hydraulic type, but in some cases it may be an electromagnetic device which could therefore be controlled directly by the electronic probe 10 opening and closing the circuits d power supply of the electromagnetic device replacing the jack 7.

As shown in fig. 1, the disc 3 is guided on its periphery by rollers 11 arranged in the horizontal plane parallel to the central axis of the ends of the shafts 1 and 2 and held in the slitting zone by rollers 12, 13 thus ensuring centering correct of the periphery 3a of the disc 3 relative to the slitting wheel 4. The rollers 12, 13 are mounted on shafts 12a, 13a secured to the support 6 in a U shape.

The above description therefore shows that the shaft ends 1 and 2 forming the support of the slitting disc are in a fixed position but due to the possibility of limited angular displacement of the support 6 in a "U" shape and of the correct maintenance of the periphery. 3a of the disc 3 by the rollers 11, 12, one can easily make up for the differences in flatness of the disc 3 and the irregularities coming from the release of the internal tensions during the slitting work.

In fig. 2, the support 6 is shown in a "U" shape of the machine which is mounted on the bench and which carries a shaft 5 driven in rotation on which is mounted at least one slitting wheel 4. As in the previous case, the disc 3 is held on its periphery 3a by rollers 11, 12 mounted idly on axes 11a, 12a. On the other hand, the disc 3 which is pierced in its center by a channel 3b tightened by a flange 20 by means of a bolt 21 on a hub 22 is guided and driven in rotation by rods 23, 24 secured to a rotating shaft 25 in the direction of arrow F5 for example. The rod (s) 23 each having a head 23a allow the positioning of a helical spring 27 between the shaft 25 and the hub 22 while the rod (s) 24 simply allow the hub 22 to be guided relative to the shaft 25 due to the fact that the ends 24a of each rod 24 are placed between an overhanging crown 28 provided inside the recess 29 hollowed out in the hub 22. Thus it is possible to obtain very slight displacements to the right and to the left according to the arrows F6, F7 of the disc 3 to automatically catch up with the deformations of the disc or compensate for the release of internal metal tensions. In addition, it is also possible to provide, as in FIG. 1, an electronic feeler (not shown) which then acts by means of a hydraulic cylinder or similar member on the hub 22.

In this way, it is easy, with this machine, to perform a deep slitting of the periphery 3a of the disc 3.

In fig. 3, the mounting of the wheel 4 is identical to that of FIG. 1 and therefore bears the same references while the mounting of the disc 3 is identical to that described for FIG. 2 and therefore bears the same references. There is thus obtained a floating mounting of the thumb wheel 4 and a floating mounting of the disc 3 thus ensuring automatic and perfect catching up of all the deformations of the flatness of the disc 3 as well as compensation for any release of internal tensions of this disc during the slitting from its periphery 3a.

The machine thus described therefore allows quick easy work of slitting the periphery of the disc to varying depths but which can for example be between 70 to 180 mm.

Although it has been described for the maintenance of the wheel 4 or of the disk 3 of the hydraulic and mechanical devices in order to ensure a floating assembly, one can use, instead of the hydraulic device, a pneumatic and even electric device by replacing the double-acting cylinder 7 and the guiding device constituted by the hub 22 and the rods 23, 24 by electromagnets, small hydraulic or pneumatic cylinders to provide the same service.

Similarly, the servo rollers 11, 12, 13 can be mounted on shafts held by very sensitive means, for example of the electrical type, in order to control the exact position at each working instant of the disc 3 during the slitting operation. It should also be noted that the feelers 10 can be electric, hydraulic, pneumatic or other.

As indicated above, the machine described is adapted and designed to allow the deep splitting of the crown at the chosen location whatever the flatness of this crown and whatever the internal tensions which are released at the time deep slitting but this machine requires, in accordance with the invention, the use of at least one wheel 100 of great thickness "E" which is substantially between eight to ten times the thickness "e" of the sheet to be slit and which is in fig. 5, the sheet metal constituting the wheel 102 whose central web 102a has been previously stamped to give it the desired desired shape.

The wheel 102 is mounted, as described above, on two ends of axes 103a, 103b driven by floating members represented here by the blocks 104. It should be noted that the outside diameter of the wheel 100 indicated by "d" is equal to at least one third of the outside diameter "D" of the disc 102. However, it should be considered that "d" is most often between 35 to 40% of "D". In certain cases, the diameter of the wheel can be equal to 7/10 ° of the diameter "D" of the disc 102.

In addition, and as shown in FIG. 5, the angle "A" of the wheel 100 is between 60 and 90 ° and has a peripheral terminal shape 100a which is not sharp but on the contrary slightly rounded.

Thus the disc 102 is forced to follow the wheel 100 because the latter is mounted, as has been said previously, on oscillating members 105 giving permanent centering thus making it possible to obtain the deep slitting of the crown of the disc 102 by creating wings 106, 107 of the same thickness which can, when the deep slitting is completed, be easily shaped to finally obtain the support of the tire.

During slitting, the slitting zone is maintained by mechanically driven rollers or rollers driven by electronic or electrical control in order to easily and immediately compensate for flatness defects and internal tensions.

During the slitting, the working area is permanently sprinkled with a special oil having qualities depending on the material to be slit in order to avoid the seizure of the thumbwheel 100 in relation to the disc or the uprooting of metallic molecules in zones of least resistance. Most often, a fine cutting oil having a viscosity of 380 ° centipoise at a temperature of 20 ° C is used.

Although in the above description we mentioned the presence of a wheel 100, the work can be carried out by two or more wheels simultaneously, wheels having the characteristics described above and working under oil bath as explained in what precedes.

The knobs are made of a hard material which can be a special steel and in some cases even a special synthetic resin.

Claims (8)

1 - Machine for slitting deep in the periphery of non-planar discs intended for obtaining tires with pneumatic tires, characterized in that the splitting disc 3 is rotated on a floating support, that is to say compensating flatness irregularities automatically while the slitting wheel (s) (4) are mounted on a drive device rigidly supported on a fixed frame. 2 - Machine according to claim 1, characterized in that the mounting of the slitting disc (3) is mounted on a floating rotary support and the slitting wheel (s) (4) being also mounted on a drive device which can be move as necessary on a frame designed for this function. 3 - Machine according to one of claims 1 and 2, characterized in that it comprises a rigid frame on which are mounted two ends of shafts (1, 2) rotated in synchronism, these two ends of the shaft carrying the disc or blank (3) to be slit deeply on its periphery then the aforementioned frame carries at least one U-shaped support (6) articulated on an axis (6a), this floating assembly being subjected to the action of a motor member allowing to follow the deformations of the disc (3) in order to allow at least one slitting wheel (4J rotating on a driven shaft (5) imperatively to score and cut deeply the periphery of the disc (4). 4 - Machine according to one of claims 1 to 3, characterized in that the drive members allowing the angular displacement of the slitting wheel (s) (4) consist of an electronic feeler acting by via an electrical connection on the distribution drawers of a double-acting cylinder (7) thus controlling, via a ball bearing (9), the angular displacement of the support (6) in a U carrying the slitting wheel (s) (4). 5 - Machine according to one of claims 1 to 4, characterized in that the floating support of the disc (3) to be deeply slit consists of a rotary shaft (.25) whose end carries guide rods (23, 24) allowing the angular displacement of a hub (22) produced in two cylindrical parts connected by a bolt (21.), this hub which carries in its center the disc (3) to be split returning to its rest position after a displacement angular due to springs or elastic elements (27) centered on one or more rods (23). 6 - Machine according to one of claims 1 to 5, characterized in that both the support (22) of the slitting disc (3) that the support (6) of the slitting wheel or knives are mounted floating and under the control electric, pneumatic or other sensors. 7 - Machine for slitting deep in the periphery of non-planar discs intended for obtaining tires with pneumatic tires in which the disc to be split is rotated on a floating support, that is to say automatically compensating for irregularities flatness and the release of internal tensions of the material constituting the disc at the time of deep slitting while the slitting wheel (s) are mounted on a drive device rigidly supported or floating on a fixed frame according to claim 1, characterized in that the slitting wheel (s) (100) have a thickness "E" equal to seven or ten times the thickness "e" of the slitting disc (102), than the diameter "d" of the wheel (s) (100) is between 30. to 70% of the external diameter "D" of the disc (102), that the identical angle "A" of each wheel (100) is greater than 60 ° and can go up to 90 °, that the peripheral end of each wheel (100) is slightly obtuse and not cutting and that during the working phase for deep slitting the working area of the wheel (s) (100) is permanently in an oil bath to prevent seizure of the wheel (s) and also avoid tearing off metal molecules on the disc. 8 - Machine according to claim 7, characterized in that an oil is used for fine cutting having a viscosity of substantially 380 centipoise at a temperature of 20 ° C.

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