DE1157382B - Machine for the production of pneumatic vehicle tires - Google Patents

Description

The invention relates to a machine for producing pneumatic vehicle tires, in particular radial tires, with a building drum used to apply and shape the carcass ply, the two rigid, has collapsible end walls and an elastic inflatable body forming the jacket, using a support body for the tread and, if necessary, for other structural parts.

The production of carcasses for pneumatic vehicle tires is usually carried out in that on a rotating metal drum of cylindrical shape various layers of shot-free rubberized material Fabrics are wound up in such a way that the cords are at a certain angle with respect to each other placed on the generatrix of the drum itself, with each layer an opposite one Has an incline to the previous one.

The wound layers are wider than the drum, and both of their protruding ends are wrapped around a rubberized bead ring or wire insert.

Other strips of rubberized fabric or made of are then applied to the entirety of the layers Rubber and finally a very thick rubber band, which represents the tire tread.

To ensure good adhesion between the various components of the green tire, are they "rolled up" during its manufacture, i. h., they are against the drum by means of rollers, which move in a parallel direction with respect to their axis, and by means of other rollers which rotate around the drum edges, pressed so that they cover the parts of the wire insert of the layers. When manufacturing is complete, the green tire must be removed from the drum and because the inner diameter of the wire insert is considerably smaller than the outer diameter the drum, it must be able to be pulled out, i.e. i.e., it must ζ. B. from different parts be constructed, which is connected to the axis of rotation by means of a complicated and expensive device are.

The green tire removed from the drum has a cylindrical shape, and it must therefore be brought into the tire shape prior to vulcanization in order to facilitate its insertion into the vulcanization mold. This operation is carried out on special devices called tire molding machines. The transition from the cylindrical shape to the tire shape thereby becomes a machine for manufacturing
of pneumatic vehicle tires

Applicant:
Pirelli Societä per Azioni, Milan (Italy)

Representative: Dr. E. Wiegand, Munich 15,

and Dipl.-Ing. W. Niemann,
Hamburg 1, Ballindamm 26, patent attorneys

Claimed priority:
Italy of November 13, 1952 (No. 13 537)

Marcello Vanzo, Dr.-Ing. Dario Giletta

and Ulisse Nuara, Milan (Italy),
have been named as inventors

achieved that the cylindrical green tire with simultaneous inflation with compressed air an axial Compression is exposed.

Since the different layers are wound onto the drum in such a way that their cords cross each other, This arrangement of the cords allows the transfer of the green tire from the cylindrical Shape into tire shape; during this transition the angle between the cords changes according to the deformation. During the usual tire molding process takes place as a result of inflation with compressed air an angular displacement of the cords takes place, which is sudden and irregular; it therefore, abnormal elongations of the individual cords forming the plies can occur. Further During the molding process, the parts that are made entirely of rubber (tapes and tread) considerably stretched to from the original diameter to the mold diameter pass over, and they are therefore subjected to high stresses, which anomalous deformations and bring about corresponding changes in thickness at various points on the circumference can. These changes in thickness have an adverse effect on the balancing of vulcanized tires the end. Furthermore, the carcass may be compressed in the axial direction must that the compression isn't really

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is exerted along the axis direction, whereby according to the invention the end walls of the Aufdie Danger of the anomalous deformation drum and the support body described symmetrically from gen is increased significantly. Both sides inevitably against each other and there are rigid building drums known that can be moved away from each other, and their inner end pieces single cylindrical rigid, on both ropes ί can be reached essentially at the same time, th open body exist on which one or through the training according to the invention are Arranged several annular, inflatable bodies obtain numerous advantages: The expensive, from the or from a rigid cylindrical drum that can be pulled out on both cambered green tires Sides closed by means of rigid shells, has been replaced by a simple device whose one firmly and whose other against them or away i-> and the green tire is axially displaceable while it is being produced, the position being formed on the same machine. The previous one Shells due to a plurality of coaxial telescoping disadvantages described standing can therefore not like sliding rings are connected, which occur one more. There are no abnormal elongations cylindrical inflatable jacket on top of the cord fabric, as the green tire passes through have, the ends of which on the above-mentioned shells 15 deformation of the expandable drum surface, are attached airtight. which is permanently attached to it, is formed. The Ver-Es are also building drums for the molding is therefore performed, and the layers Position of pneumatic tires known, the two rigid lines are not directly subjected to compressed air, and the ten walls, one of which is fixed and the axial compression of the tire by the other is movable and at which the ends of a 20 gradual and controlled movement of the approach elastic, cylindrical, inflatable, not replaced by any rigid end walls which form the side of the drum its interior arranged rigid body borrowed close.

supported jacket are attached airtight, with the addition of no abnormal deformations movable end wall when the pressure in the green tire changes more occur, as this after Inside the building drum in the axial direction, the crowning is brought into the shape and none is slidable. Stretching is subjected to more; As a result, none of the above-mentioned drums will get better centered tires after vulcanization Machines, however, ensure that they keep the same. In particular, the machine can also be moderate and turned symmetrically to the carcass median plane when making radial tires see carcass crowning. 3 ° should, d. H. by applying non-expandable

The rigid, with the body parts indicated on their outer surface on the carcass,

The green tires are arranged in two stages on the

mine have no way of being built up in an axial rieh- same machine, and it will be finished-

to push them together, and for the other molded green tires obtained after manufacture.

the drums mentioned above, which are a single rot.

have sliding side wall, is created while the machine is based on the drawing of both Approach movement of this side wall to the example described in more detail.

fixed side wall a progressive displacement Fig. 1 is a vertical longitudinal section through the

the center plane of the drum against the fixed side complete machine;

wall, which is why the drum shell during its 4 ° Fig. 2 is a horizontal longitudinal section through the

Inflation and simultaneous approach of the machine;

sliding wall against the fixed side wall Fig. 3 is a front view of the rolling device,

none with respect to the sliding drum means partially cut;

assumes a flat symmetrical configuration and FIG. 4 is a side view of the rolling device,

partially cut from the casing onto the carcass arranged on it;

practiced effect is also asymmetrical to Fig. 5 is a horizontal section through the

Drum center plane affects. rolling device;

Furthermore, the combination of a rigid, in longitudinal Fig. 6 is an individual representation of the drum and

direction domed drum with two on both of the device for applying the bead cores;

Sides of the same movably arranged carrier ring 5 <> Fig. 7 shows in section the drum and the rings,

gene known that serve to provide a uniform approach to which the tread is applied;

joining the beveled ends of FIG. 8 is a similar illustration and shows the

Carcass plies before applying these plies after applying the tread and drum

to allow the drum to form before rolling;

of wrinkles is avoided, which would otherwise occur in the case of a 55 Fig. 9 shows the drum after rolling on the

with a tread removed from the wreath on both sides - previously applied in section.

unavoidable profile provided drum In Figs. 1 and 2, the main part of the machine,

would be. the drum, shown in detail. it consists of

Since this drum is rigid, neither the opposing two end walls 1 and 2, between which an annular

term approximation of the beads of the carcass, around them to 60 miger jacket 3 is stretched from rubber, which means

to bring their final distance, nor the metal plates 4 and 5 on the end walls 1 and 2, respectively

complete crowning of the carcass, which is easily attached. This arrangement is completely airtight so

bulges like the drum profile is possible and therefore that the jacket 3 by introducing compressed air into

also the application of the tread and given the drum inflated through an opening 6

Otherwise, other structural parts can be placed on the largest end.

valid carcass diameter not possible. The end wall 1 is elongated with an

In the case of the above-mentioned machine for the production of pipe 7 rigidly connected on a hollow shaft 8

of pneumatic vehicle tires, in particular radial tires, is displaceable and by means of a wedge 9 with this

forms a rotatable unit. The end wall 2 is rigidly connected to a pipe 10 which is placed on the pipe 7 is displaceable, but is prevented from rotating with respect to the tube 7 by a wedge 11. on In this way, the end walls 1 and 2 can be brought closer to or removed from one another, whereby they however, form a unit rotating with the hollow shaft 8. The shaft 8 is on the one hand by a Bearings 12 and, on the other hand, carried over the tubes 7 and 10 by a bearing 13. The wave 8 is through a motor 14 is driven via pulleys 15 and 16.

The tube 7 is connected by a thrust bearing 17 to a plate which has two nuts 18 and 19 carries, which in turn with threaded parts 20 and 21 of double-threaded shafts 22 and 23 in Engagement stand. The tube 10 is connected to another plate by a thrust bearing 24, which two nuts 25 and 26 which in turn engage with threaded parts 27 and 28 of shafts 22 and 23, respectively stand. Each of the shafts 22 and 23 has two threads in opposite directions. The cones of the Shafts 22 and 23 rotate in bushings which are in two side walls 29 and 30 of a housing 31 are used. The shafts 22 and 23 are (both in the same direction) by a Motor 32 rotated, which is coupled to a reduction gear 33 through the following gears is: a gearwheel 34 wedged on the gear shaft, a gear 35 wedged on the shaft 23, a loosely seated on the shaft 8 gear 36 and a tightly wedged on the shaft 22 gear 37. From the above description it can be seen that the end walls 1 and 2 depending on the direction of rotation of the shafts 22 and 23 driven by the motor 32 towards and away from one another move.

On both sides of the drum two caps 38 and 39 are provided which carry rings 40 and 41, in the second stage of the tire manufacturing process, as described in more detail below, must the rings 40 and 41 are brought closer to one another. The approach movement for the ring 40 wearing The cap 38 is implemented by a piston 42, the rod 43 of which is connected to the cap 38. Of the Piston 42 moves in a cylinder 44 which is carried by a sheet metal frame 45 on the a base plate 58, with which the housing 31 is rigidly connected. For the cap 39, which the Ring 41 carries, the approximation movement (Fig. 2) is brought about by two pistons 46 and 47, which move in cylinders 48 and 49, which are fastened to the side wall 29 of the housing 31. the Piston rods 50 and 51 of pistons 46 and 47 are connected to a crosspiece 52 carrying cap 39, the hub 53 of which can be displaced on the tube 10. The pistons 42, 46, 47 are pressurized with compressed air supplied by the same source and are therefore started at the same time. The possibility of The approximation of the caps 38 and 39 to one another is also used for the application of the bead cores exploited by using two symmetrical devices. The following will only that for the cap 38 is described. The cap 38 carries a pressure ring 54 (Fig. 6), which of Bolt shafts 55 is held, on which it is slidable and by compression springs 56 always in Direction on the end walls 1 is pressed.

As stated above, the structural parts of the green tire must be rolled on during manufacture will. The rolling process is carried out when the green tire is already formed, and the rolling device is therefore designed in such a way that the disks are pivoted about an axis can that goes through the center of a curve of the shaped tire tread, with a longitudinal movement of the slices in a direction parallel to

ίο the drum axle is not required to start rolling the unshaped carcass.

The device shown in Figs. 3, 4 and 5 is provided with a workbench 57, which on the base plate 58 is arranged. On the bench 57

ig is a carriage 59 is arranged on guides can slide and is driven by a spindle 60, which is connected to a with the carriage 59 Nut 61 is engaged. On the carriage 59, a pin 62 is arranged on which a

ao gear 63 is keyed. Furthermore, a bushing 64 is rotatably placed on the pin 62, with which a gear wheel 65 is firmly connected. At the upper end of the pin 62 and the socket 64, two symmetrical parts 66 and 67 are fixedly attached, on which pivot arms 68 and 69 are located, which carry the roll-on disks 70 and 71, respectively. Since the arms 68 and 69 are symmetrical, only one arm, namely the arm 68, will be described below with reference to FIG.

The arm 68 is articulated to the part 66 and carries a cylinder 72 in which a piston 73 can move against the action of a spring 74. A connecting rod 76 is movably attached to the piston by means of a pin 75, the opposite end of which is pivotably attached to an extension of the part 66. A rotary movement of the arms 68 and 69 is brought about by a reduction gear 77 which, via toothed wheels 78 and 79 (FIG. 5) and a chain 80, actuates a worm 81 which meshes with a wheel 82 with helical teeth. Gears 83 and 84 are keyed to the axis of said gear wheel 82. The gear 83 meshes with the gear 63 and transmits the rotary motion to the arm 68; the gear 84 transmits the rotational movement to the arm 69 in the opposite direction to that of the arm 68 via a free-running pinion 85 and the gear 65.

The operation of the machine in the various stages of the tire manufacturing process is short the following:

a) applying the layers to the drum,

b) applying the bead cores,
c) forms,

d) application of the running surface,

e) rolling on the running surface, applying and rolling on the side walls,

f) pulling off the cambered green tire.

a) Applying the layers to the drum

This operation is carried out in the same way as with the machines that are usually used. the The drum is set in circulation and layers of rubberized fabric are placed one on top of the other wound with their edges protruding from the sides of the drum. The shell 3 of the drum

(Fig. 1) is by means of a
kept tense all the time.

low air pressure

b) Applying the bead cores

After the protruding edges of the layers are turned against the axis of rotation of the drum compressed air is applied to pistons 42, 46, 47 (FIGS. 1 and 2), causing caps 38 Rolling arms 68 and 69 has been let in, the discs 70 and 71 lie on the running surface and press them against the formed layer structure. By turning the drum, the tread is placed on it for adhering to the outer periphery of the molded sheet structure along the free space brought between the rings 40 and 41. By releasing the compressed air from the cylinders 72 and 72 & IS are arms 68 and 69 by spring 74

and 39 are approached to the drum. Below to and a corresponding spring in the cylinder 72 ^6is

only the effect of one cap 38 is described with reference to FIG. 6, since the two caps work the same way in mirror image. The ring 54 on which the bead core opposite the end wall 1 brought back to their rest position. Then when compressed air is applied to pistons 42, 46 and 47 is, the caps 38 and 39 return to their rest position and the tread therefore remains fixed

rests, remains standing while the cap moves against 15 on the layer structure due to the adhesion on which the drum moves, the springs 56 together part of their surface on which they are pressed by the crowd. The bead core is pressed under the washers 70 and 71 (Fig. 8). Press the bolt 55 in tight contact with the
Brought layers to which it sticks. Thereafter
is compressed air in the opposite direction to the 20
Pistons 42, 46, 47 brought into action so that

e) Rolling the running surface

the caps return to their rest position, c) ^{Shaping By allowing compressed air to enter the cylinders 72 and 72 6 / s} , the roll-on disks 70 and 71 are pressed against the running surface. When the reduction gear 77 is started and the drum rotates at the same time, the arms 68 and 69 rotate about an axis which passes through the center of the curvature of the shaped tire profile. The discs 70 and 71, which permanently by the compressed air in the cylinders 72 and 72 ^{6 / s} against the tire

After the bead cores are applied on both sides and the protruding edges of the plies around they are lying around, the molding process begins. The following work stages are carried out:

First, the shafts 22 and 23 are pressed by means of the 30 blank, causing the motor to run 32 rotated so that the end walls 1 and 2 surface on the molded green tire (Fig. 9). At the to be brought closer to each other; secondly, the air pressure inside the drum is increased, and the

Sheath 3 bulges outward as soon as the forehead end of the roll-on process stops the arms 68 and 69 automatically; the compressed air escapes from the cylinders 72 and 12 ^bis and the disks 70 and 71

wändel and 2 are approached; third, 35 are advanced from the drum. If that is compressed air on the pistons 42, 46 and 47 to the reduction gear 77 in the opposite direction

Brought action so that the caps 38 and 39 come near the drum. The caps 38 and 39 come with the end walls 1 and 2 in device, respectively, the arms 68 and 69 are in brought back the starting position.

According to the changes in the diameter of the green tire to be built on contact and then follow the joining movements, the position of the green tire changes the end walls. After the final shape- the center of the curvature of the tire contour, which extends longitudinally position has been reached, keep the end walls 1 moved their diametrical axis. Since during the and 2 on automatically. Roll the axis of rotation of the arms through the middle

In this position (Fig. 7) the rings are the curvature must go is a complete 40 and 41 close together; however, they touch each other 45 displacement of the roll arm carrying

not, but between them, as shown in FIG. 7, there is a space so that they are above the Leave the carcass uncovered for a corresponding stretch.

d) Application of band-shaped parts and the running surface

Slide provided in the transverse direction. The carriage 59 can, as can be seen from Fig. 4, the Drum axis can be approached and removed from this by the spindle 60, which with the nut 61 is engaged, is rotated in opposite directions.

The rings 41 and 42 have an outer cylindrical surface and form when approached to each other are, with the layer structure, a cylindrical surface, in the center of which is the outer surface of the Layers appears. The band-shaped parts and the running surface are applied to this surface with the result that they are centered, since they are bordered by two centering projections, which on the rings 41 and 42 are attached. The band-shaped parts and the tread are successively applied by rotating the drum

f) peeling off the finished tire

The finished tire is removed from the drum by bringing the end walls 1 and 2 together further and applying a vacuum inside the drum so that the jacket 3 is sucked inwards, removed.

Under these conditions, the building drum takes the form of a disc of small thickness, and the bead of the manufactured green tire can easily go over it after traveling along a diameter has been bent until it takes the shape of a

which in turn has assumed the rings 40 65 ellipse, the transverse axis of which is larger and rotates 41 by the friction which is the shaped than the pulley diameter and which the through-carcass blank exerts on it. Knife plane of the green tire with respect to the-After compressed air in the cylinder 72 or 72 ^6iS that of the disc has been inclined.

The description of the machine includes the manufacture of pneumatic tires for motor vehicle wheels been portrayed. It can be seen, however, that the machine also produces green tire blanks can be used for the wheels of any vehicles (such as aircraft, motorcycles or Tractors) can be used.

Claims (10)

PATENT CLAIMS: IO 1. Machine for the production of pneumatic vehicle tires, in particular radial tires, with a building drum which is used to apply and shape the carcass ply and which has two rigid, collapsible end walls and an elastic inflatable body forming the jacket, using a support body for the tread and, if necessary, for other structural parts , characterized in that the end walls (1, 2) of the building drum and the support body can be moved symmetrically from both sides towards each other and away from each other and their inner end position can be reached essentially at the same time. 2. Machine according to claim 1, characterized in that the support body consists of two on both sides the building drum arranged, coaxial with her rings (40, 41) and with a Drive and control device is provided. 3. Machine according to claim 2, characterized in that the rings (40, 41) centering projections for the tread strip and any other external structural parts. 4. Machine according to claim 1, characterized in that the end walls (1, 2) seats for have the corresponding tire bead. 5. Machine according to claim 2, characterized in that the rings (40, 41) on axially displaceable Caps (38, 39) are arranged, each of which on its facing the building drum Side has a device for supporting and for sliding the bead rings onto their seats. 6. Machine according to claim 5, characterized in that the devices for supporting and Sliding on the bead rings each have a carrier ring (54) which is firmly connected to the cap Bolt shafts (55) mounted displaceably and by compression springs (56) from the cap (38, 39) can be held at a distance. 7. Machine according to claim 1, characterized in that the end walls (1, 2) from their Working position can be moved into an approximate contact position. 8. Machine according to claim 1, characterized by a device for generating a Underpressure inside the drum for the purpose of sucking in the elastic jacket when approached End walls (1, 2). 9. Machine according to claim 1, characterized in that the end walls (1, 2) on one rotatable, cantilevered hollow shaft (8) mounted so as to be axially displaceable and concentric to one another and pipes (7, 10) arranged on the hollow shaft are fastened. 10. Machine according to claim 2, characterized in that a rolling device on the Tread strips in the area of the space between the two rings (40, 41) Pressure can be set and after removal of the rings (40, 41) on every point of the tread strip and the carcass is slidable. Considered publications: German patent specifications No. 834 012, 856 513,
154; French Patent No. 372 292; British Patent No. 214,704; U.S. Patent Nos. 1789143, 2 394464, 896, 1777405, 1854813, 2381379, 2045545. For this purpose 2 sheets of drawings © 309 748/278 11.63