This application is a 371 national phase entry of PCT/EP2018/061570, filed on May 4, 2018, which claims benefit of French Patent Application No. 1754013, filed May 5, 2017, the entire contents of which are incorporated herein by reference for all purposes.
The disclosure relates to the field of manufacturing tires for vehicles.
The present disclosure relates more specifically to an automated device for gripping and handling a tread for a tire.
The disclosure also relates to an installation for moving a tread for a tire, which is provided with said device.
A tire for the wheel of a vehicle generally comprises a tread, which is applied to the outer surface thereof before it is vulcanized.
This tread is in the form of a strip of a green rubber compound, that is to say one which has not yet been cured. It incorporates a plurality of longitudinal furrows, that is to say grooves that extend along its entire length and to a particular depth from its outer surface and thus determine a given profile of the tread of the future tire. In other words, the “profile” of the tread corresponds to its contour in cross section.
The tread is manufactured in the form of a continuous strip that is stored on reels. Next, this continuous strip is unrolled from the storage reel, cut to the appropriate length for surrounding the circumference of the tire, and then moved and positioned on a cylindrical form (which may be either a tire blank or a cylindrical drum for temporary storage prior to laying on the blank). Finally, the two ends of the tread are butted together with precision.
In the prior art, the handling of the tread between the outlet of the cutting tool and the cylindrical form takes place manually.
However, it would be desirable to have an automated device for this purpose.
Already known, from the document WO 2007/138374, is a device for gripping and handling a tread for a tire, which comprises a module for pricking this tread and means for moving said module vertically and horizontally.
Likewise known, from the document EP 2 931 509, corresponding to WO 2014/090983, is a device for transporting a carcass reinforcement ply, said device being used in a method for manufacturing a tire blank. That device comprises a suction-cup gripping module.
None of the devices described in those documents makes it possible to optimize the gripping of the tread or reinforcement in terms of modularity and safety, however.
Therefore, an objective of the disclosure is to propose an automated gripping and handling device that makes it possible to automatically transport a tread from the outlet of the cutting tool to the cylindrical form while keeping it under tension, that is to say slightly stretched in order to prevent its retraction.
Another objective of the disclosure is for the device not to damage the tread while it is being moved and for it to be able to function with treads having different profiles.
To this end, the disclosure relates to an automated device for gripping and handling a tread for a tire.
According to the disclosure, this device comprises at least one module for pricking said tread,
By virtue of these features of the disclosure, it is possible to prick the tread effectively, to keep it under tension without damaging it, and to transport it, the movable pricking plates making it possible to adapt the device to treads having different profiles.
According to other advantageous and non-limiting features of the disclosure, considered alone or in combination:
said movable pricking plate being disposed inside the vertical guiding space such that its upper end rests against the inflatable sleeve when it is in its bottom position and such that its upper end deforms said inflatable sleeve when it is at a height greater than said bottom position,
said inflatable sleeve tending to push said plate back downward when it is inflated;
The disclosure also relates to an installation for moving a tread for a tire.
According to the disclosure, this installation comprises:
Advantageously, the installation also comprises a laying form that is able to receive said tread at the end of said moving belt.
Further features and advantages of the disclosure will become apparent from the description which will now be given thereof, with reference to the appended drawings which show, by way of non-limiting example, one possible embodiment thereof.
In these drawings:
Referring to
This installation 1 comprises:
The moving belt 11 is preferably a motorized belt, comprising an endless belt driven at its two ends by two rotary rollers.
Likewise preferably, this installation 1 comprises a cylindrical laying form 12 that is able to receive the tread B at the end of the moving belt 11.
The installation 1 is fed from a product reel BP disposed upstream of the installation 1, a cutting device C being interposed between the product reel BP and the installation 1. This cutting device C makes it possible to cut the necessary length of tread B before the latter is moved with the installation according to the disclosure.
Referring to
Preferably, the means 21 for moving horizontally comprise a carriage 210 comprising a vertical sheet 211 and a horizontal sheet 212 that are joined together perpendicularly, and two brackets 213, which are each fastened to one of the two ends of these sheets, perpendicularly to the two sheets 211, 212. Each bracket 213 supports, in its upper part, a slider 214 that is disposed horizontally and oriented parallel to the direction X-X′.
Each slider 214 is designed to be able to cooperate with a shoe 100, shown only in part in
The carriage 210 can thus move in the direction of movement X-X′, either in a first direction XA, known as the forward direction of movement AV, that is to say towards the laying form 12 in
The movement of this carriage 210 is actuated automatically, for example by virtue of a toothed-belt system actuated by a motor.
Preferably, the means 22 for moving vertically comprise a carriage 220 formed by a vertical sheet 221, perpendicular to the axis X-X′, which is fixed at its bottom to the upper face of a horizontal sheet 222, substantially at the center thereof.
The pricking modules 3 are fastened to the lower face of this horizontal sheet 222.
Advantageously, at least one bracket 223, in this case two, are fastened to the upper face of the horizontal sheet 222 and to the rear face of the vertical plate 221. These brackets 223 act as stiffeners.
At least two guide rails 224, preferably three, are fastened to the front face of the vertical plate 221, that is to say the face towards the front AV of the installation. These guide rails 224 are vertical and mutually parallel.
The rear face of the vertical plate 211 of the carriage 210 supports two guide shoes 225 and a locking member 226.
Each shoe 225 is an elongate element, which is fastened vertically to the plate 211 and provided with a vertical groove 2250. The groove 2250 is shaped so as to be able to receive the guide rail 224 located opposite it, such that this rail 224 can slide. The two shoes 225 are disposed opposite the first and the third rail 224.
The locking member 226 is disposed between the two shoes 225 and is able to cooperate with the central guide rail 224.
This locking member 226 comprises for example three superposed locking/braking modules 2260, which are able to prevent the sliding of the second rail 224.
The shoes 225 are also provided with at least one locking/braking module 2251 that is able to prevent the sliding of the lateral guide rails 224.
The means 22 for vertically moving also comprise a double-acting hydraulic or pneumatic cylinder 227, which is visible in
This cylinder comprises a body 2271 and a rod 2272. The body 2271 is secured to the means 21 for moving horizontally, and is fastened for example by its upper part to the horizontal sheet 212. The rod 2272 is fastened to the means 22 for moving, for example to the upper face of the horizontal sheet 222. A reverse setup is likewise possible.
The actuation of this cylinder 227 makes it possible to move the carriage 220 vertically, with respect to the carriage 210, in a direction Z-Z″, perpendicular to X-X′, specifically in two opposite directions, namely upwards (direction ZA) and downwards (direction ZB).
As will be explained in more detail below, this vertical movement makes it possible to prick the tread B, or, conversely, to separate the modules 3 therefrom.
The device 2 and the means 21 for moving horizontally and means 22 for moving vertically are controlled by a central control unit 13, shown only in
An exemplary embodiment of a pricking module 3 will now be described in conjunction with
The pricking module 3 comprises a frame 4 which supports a fixed pricking assembly 5 and two “movable” pricking assemblies 6 that are disposed on either side of the fixed pricking assembly 5.
It is apparent from
The upper part 41 has the overall shape of a rectangular parallelepiped, which is pierced right through by a longitudinal bore 410, preferably of cylindrical shape, of longitudinal axis Y-Y′. This bore 410 delimits a housing for receiving an inflatable sleeve 7.
The lower wall of this upper part 41 is solid in its central part situated opposite the fixed pricking assembly 5 and has two longitudinal slots 411 on either side of this central part.
As is more clearly apparent from
The housing 410 is closed off at one of its ends, in this case the end situated on the right in
The inflatable sleeve 7 is closed off at its end 70 situated opposite the wall 412. It is open at its opposite end.
A stopper 413 is inserted in the mouth of the housing 410 situated at the opposite end from the one closed off by the wall 412. This stopper 413 pinches the open end of the inflatable sleeve 7, specifically in a sealed manner.
The stopper 413 is provided with a drilling 414, for example in the shape of an L, which is continued on the outside by a connector 415, in this case for example a bent connector. The connector 415 is configured to be able to be connected to an air supply for the sleeve 7, this not being shown in the figures. The sleeve 7 can thus be supplied with air and inflated.
As is more clearly apparent from the view in cross section in
The middle zone 421 is pierced right through by a cylindrical bore 423, which extends along a longitudinal axis Y1-Y′1 parallel to the axis Y-Y′ and perpendicular to the direction X-X′. This bore 423 allows the reception of a cylindrical thrust shaft 424.
As is visible in
As is more clearly apparent from
Moreover, each spike 430 of the first bar 43 is spaced apart from the spike 430 of the second bar 43, situated on the opposite side in the direction X-X′, by a spacing known as “second spacing” P2.
Preferably, the spacings P1 and P2 are the same.
The bars 43 and thus the spikes 430 are secured to the frame 4. This central part of the frame 4 is said to form a fixed pricking assembly 5, in that said spikes 430 are fixed with respect to the frame 4 of the module 3. These spikes 430 follow the vertical or horizontal movement of the module 3, however.
It would also be possible to have more than two rows of spikes 430.
The two lateral zones of the lower part 42 of the frame 4 that are situated next to the movable pricking assemblies 6 will now be described in conjunction with
Here, the lower part 42 comprises only the wider upper zone 420 and the less wide middle zone 421.
The lower part 42 has, in cross section, that is to say in a plane perpendicular to the axis Y1-Y′1, a cross-shaped housing 45.
The vertical leg 451 of this cross-shaped housing 45 extends from the slot 411 to the lower face 429 of the middle zone 421.
The horizontal leg 452 of the cross-shaped housing 45 extends from the front face 4211 of the middle zone 421 to the rear face 4212 thereof.
The leg 452 leads out opposite the bore 423.
As can be seen in
A pricking plate 47 is interposed between two adjacent fittings 46.
An exemplary embodiment of the pricking plate 47 will now be described in more detail in conjunction with
The pricking plate 47 has a cross-shaped overall shape.
It is formed of a flat sheet 470 that is longer than it is wide and has a small thickness, having substantially the shape of a rectangular parallelepiped. This sheet 470 has two opposite lateral faces 471, a front face 472, a rear face 473, thus named since they are oriented towards the front AV and the rear AR, respectively, of the device 2 of the installation 1. Two arms 474 project from each of the front face 472 and rear face 473, substantially halfway up the latter.
The sheet 470 also has a flat lower face 475 which is continued by a front spike 476 and a rear spike 476′, which are spaced apart from one another at their tips by a spacing known as “third spacing” P3, which is preferably the same as the second spacing P2 (see
The face 475 forms a flat horizontal contact surface, as will be described below.
The sheet 470 also has an upper face 477, on the opposite side from the face 475. In its upper part, it has two holes, namely an upper hole 478 and a lower hole 479, passing right through the sheet 470 so as each to lead out onto the lateral faces 471 thereof.
The width L1 of the sheet 470 of the plate 47 corresponds, allowing for sliding play, to the width L2 of the vertical leg 451 (see
The plate 47 can thus slide vertically inside the leg 451, which forms a vertical guiding space.
The two arms 474 can move in the horizontal leg 452 of the cutout 45.
The two legs 474 constitute stops for limiting the vertical travel of the plate 47. The latter can move vertically between a bottom position, shown in
In order to enlarge the contact surface between the plate 47 and the inflatable sleeve 7, the pricking plate 47 is advantageously provided with a contact head 48.
As can be seen from the detail view in
Preferably, the shape of the spikes 476, 476′ of a plate 47 is identical to the shape of the spikes 430. Preferably, this shape is pyramidal. Other shapes could be envisaged, however, as long as they make it possible to easily penetrate the rubber tread B.
As can be seen in
Finally, as can be seen more clearly in
Moreover, a thrust plate 81 is screwed, with the aid of a screw 82, to the last fitting 46, which faces the cylinder 8.
As can be seen in
The operation of the automated device 2 for gripping and handling a tread B according to the disclosure will now be described in more detail with reference in particular to
First of all, a series of steps consisting of a “profiling” cycle is carried out. This cycle has the purpose of regulating the automated gripping device 2 so as to acquire the profile of the tread B to be moved.
Initially, the tread B is present on the belt 11 for linearly moving, as shown in
Next, as shown in
The lowering continues until the stop surface 428 comes into contact with the uppermost point of the profile of the tread B situated opposite. The “fixed” spikes 430 pass into the tread B with which they are engaged. The inflatable sleeve 7 is still not supplied with air and the thrust cylinder 8 is not actuated.
As can be seen in the left-hand and right-hand parts of
As can be seen in
As can be seen in
The force F is made up of a force f applied by the cylinder 227 and by the overall weight of the automated gripping and handling device 2. This force f applied by the cylinder 227 can be adjusted depending on the cycle and/or on the product, for example on the nature of the rubber of the tread B.
During this “profiling” cycle, the force F necessary is equal to the pricking force of the fixed spikes 430 of all the bars 43 of all the fixed pricking assemblies 5.
During a “laying cycle”, which will be described below, the force F necessary is equal to the pricking force of all the fixed spikes 430 plus the pricking force of the movable plates 47 engaged with the tread B, for all the modules 3.
During a third step, shown in
Under the action of the pressure exerted by the inflatable sleeve 7, the pricking plates 47 move down into contact with the tread B until their contact surfaces 475 bear against the outer surface of the tread B against which they are pressed. This situation is the one shown for example in
The movable plates 47 that face a void in the profiled element B remain in abutment under the action of their own weight, the arms 474 resting against the faces 4521, as shown in
Note that the force F exerted by the cylinder 227 should comply with the following formula:
F>n×f1(max)×a
where F=mechanical locking (N)
n=the number of movable plates 47 per pricking module 3,
f1 max corresponding to the maximum force per pricking plate (expressed in N) at the maximum pressure admissible by the inflatable sleeve 7 (expressed in N)
where a=the number of pricking modules 3, for example in this case three.
Finally, during a fourth step shown in
In this position, the height of the pricking modules 3 is still mechanically locked by the cylinder 227. Similarly, the inflating membrane 7 remains supplied with compressed air at the pressure P.
The thrust shaft 424 then transmits the force f2 exerted by the cylinder 8 to the left-hand part of the system (in
where f1 (max)=maximum force exerted by the pricking plate (expressed in N) at the maximum pressure admissible by the inflating sleeve 7.
μ (steel)=friction factor between two steel parts,
2 corresponds to the two contact surfaces of a pricking plate 47.
During the “laying cycle” described below f2 complies with the formula:
where Tmax=maximum traction or compression force per plate engaged with the tread B (expressed in N). Finally, while the cylinder 227 is still actuated to maintain the height position of the pricking modules 3 and the thrust cylinder 8 is still active, the inflating sleeve 7 is no longer supplied with compressed air.
A negative image of the upper profile of the tread B is thus obtained, through the arrangement of the different fixed and movable spikes.
The engagement of the tread B is thus effective and the means 21 for moving the pricking modules 3 horizontally are thus actuated so as to drive the device 2 forwards (see
The cylinder 227 is then actuated so that the pricking modules 3 are lifted and separate from the tread B, then the means 21 for moving horizontally are actuated to return the device 2 to the rear, in its starting position shown in
It is then possible to start a “laying cycle”, with other treads B having the same profile as the tread that has been used to acquire the negative of the profile of this tread. While the pricking plates 47 are still fixed in their height position, the device 2 is again lowered in order to pick up a new tread B and convey it to the form 12. This step can be repeated as long as the dimension “e” is respected or as long as the profile of the tread B does not change.
On the other hand, in order to handle a tread B having a different profile, the “profiling” cycle will have to be repeated.
Number | Date | Country | Kind |
---|---|---|---|
1754013 | May 2017 | FR | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2018/061570 | 5/4/2018 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2018/202879 | 11/8/2018 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
2556305 | Vickers | Jun 1951 | A |
4052246 | Albareda | Oct 1977 | A |
4372548 | Aurich | Feb 1983 | A |
4641827 | Walton | Feb 1987 | A |
5463921 | Bellio | Nov 1995 | A |
5669602 | Ito | Sep 1997 | A |
5935377 | Sergel et al. | Aug 1999 | A |
9130485 | Prahlad | Sep 2015 | B2 |
20030070742 | Risser et al. | Apr 2003 | A1 |
Number | Date | Country |
---|---|---|
2508016 | Dec 1982 | FR |
2006015896 | Feb 2006 | WO |
2007138374 | Jun 2007 | WO |
2014090983 | Jun 2014 | WO |
Entry |
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International Search Report and Written Opinion for International Application No. PCT/2018/061570 dated Jul. 13, 2018 with Translation. |
Number | Date | Country | |
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20200061846 A1 | Feb 2020 | US |