FR2492999A1 - MECHANICAL TIME-SETTING DEVICE FOR AN ANALOG DISPLAY WATCH - Google Patents

Abstract

The time-setting mechanism comprises a shaft 112 rotatably mounted in a tube 114 in the back 6 of the watch case. The inner end of the shaft is provided with a mutilated gear 118 formed with a recess 118a. The outer end is provided with an operating blade 116 mounted for pivotal movement about the axis X1, X1 by means of swivel pins 122, 122'. The outer surface 6a of the back 6 contains a seating 126 in which the blade can be held stationary in a folded back position. The gear 118 can mesh with a time-setting adjusting wheel 22 of the going train. When the blade is positioned in its seating, the shaft is in a datum position and the recess 118c of the gear 118 is opposite the adjusting wheel 22, thereby ensuring the disengagement of these two parts. In modified embodiments, the shaft 112 can be pulled out against a bias spring to disengage the gear 118 from the adjusting wheel 22, either for free return to the datum position or to bring into mesh with the wheel 22 a fully toothed wheel which turns the hands more rapidly.

Description

The present invention relates to a mechanical device for setting the time

  a watch with an analogue display.

  More specifically, the invention relates to a

  mechanical positive time setting that is compatible with a watch of reduced thickness and which is also not visible when this watch is worn on the wrist. It is well known that mechanical watches include a controller for setting the time which, more often than not, is also used for reassembling the watch. In the case where these two functions are fulfilled simultaneously, the control member is most often in the form of a control rod or winding stem sliding in the box and in the plate of the movement. This rod actuates, via a system of levers, a sliding pinion which meshes, according to its position, with the time setting or the crown wheel for reassembly. To allow the user to easily manipulate the rod, it is provided with a cap or winding crown which makes

  protruding out of the side of the watch case.

  In the case of electronic watches with

  analog watch, setting the time of the watch can be done using one or more pushbuttons that protrude out of the middle of the watch. In this same case, the time setting can also be done by a sliding rod with several positions, as

  this is done for mechanical watches.

  It is clear that, in general, the appendage formed by the winding crown or the

  push button is not the most decisive element

  ratify the watch. It is equally clear that in the

  case of a very flat watch, the winder or the button-

  The pusher is relatively even more visible if the crown or the crankcase retains dimens-ons which

  makes it easy to operate.

  interesting to be able to house this organ in such a way

  that it is not visible when the watch is worn.

  It is for this reason that some electronic watches with analogue display are included in the

  the bottom of the box a little pusher which, when it is

  Dark, sends pulses to the electric motor.

  At rest, the head of this pusher is flush with the ex

  dull of the bottom of box. However, in the case of very flat watches, the head of the pusher can only have one

  very small area. This makes the manipulation of

  very delicate since it is necessary to simultaneously watch the dial of the watch and act on the pusher. In addition,

  this solution is of course not applicable to

mechanical watches.

  Moreover, there are a number of watches in which the control member serves

  only at the time setting. This is the case of mechanical watches

  winding machines in which the mass

  winding removes manual winding.

  This is still the case for electronic watches with an analogue display that only include the time display function. This is also the case in mechanical watches

  if a particular order is provided for the remount-

  manual step. It is therefore clear that a device providing control of the only time setting of the watch and

  which moreover would not be visible presents a real inte-

  Ret. This is why a first object of the invention is to provide a time-setting device that is not visible when the watch is worn by its owner.

  user, and that does not cause any inconvenience to it.

  A second object of the invention is to provide

  to set up a time-setting device that is

  easy and does not require any special tools

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  A third object of the invention is to provide

  such a device which, moreover, is compatible with

  a very flat watch, for example a watch whose

  Overall thickness is less than 2 mm.

  A fourth object of the invention is to provide such a device which is moreover compatible with

  a self-winding watch.

  These objects are achieved by the invention thanks to the fact that the device comprises-on the one hand a key to reset the time and, on the other hand a time setting wheel actuated by the key. The key of time setting

  includes a pivotally mounted rod in the box bottom.

  At its outer end which is level with the outer face of the can bottom, the rod comprises a pallet pivotally mounted about an axis perpendicular to the axis of rotation of the cylinder. In a rest position,

  the pallet is folded and engaged in a household

  ge in the outer face of the bottom so that the cylinder can not rotate when the pallet is in position

  rest. In an active position, the pallet

  outside the bottom of the box and allows you to control the

  votively from the stem. At its inner end, the rod is provided with a wheel having teeth on a part of

  its periphery and a notch on the rest of the

  phérie. The teeth of this wheel mesh with the time setting wheel. The part of the toothless wheel is located so that it is in front of the time setting wheel when the pallet is in the position of

rest, folded in the housing.

  Thanks to this arrangement, it is clear that the time setting device is completely embedded in

  the bottom of the box outside the phases of handing over

  re. On the contrary, when the pallet is in the raised position, the user can easily proceed with the setting

  at the time of the watch because the pallet is

  protruding from the bottom. In addition, housing

  Nit the position of rest of the wheel of time setting, 4 - which avoids any risk of blockage of the gear train by the wheel of time setting, without complicating

the mechanism.

  Other features and advantages of the

  will appear more clearly on reading the

  following description of several embodiments

  of the invention given as non-limiting examples.

  The description refers to the accompanying drawing in which:

  FIG. 1 is a view from above of a

  being self-winding comprising the time setting device according to the invention; - Figure 2 is a partial view from below of the watch case showing the time setting device; FIG. 3 is a vertical sectional view of the time-setting key along line III-III of FIG. 2; - Figure 4 is a partial top view of the bottom of the box showing a first embodiment of the key setting time; - Figure 5 is a vertical sectional view of one of the wheels of the time-setting train, along the line V-V of Figure 1;

  FIG. 6 is a diagram illustrating the film

  the watch shown in Figure 1; - Figures 7a and 7b are two half-views in vertical section of a second embodiment of the key in two different positions; and

  FIGS. 8a and 8b are two half-views in cross-section;

  of a third embodiment of the key in two posi-

different conditions.

  FIG. 1 represents, in plan view, an ultra-thin watch with automatic winding and equipped with the time-setting device according to the invention. In addition,

  in this watch, the bottom constitutes a platinum of the movement.

  On the bottom 6 of a box, a winding mass comprising an oscillating mass 10b and an arm 10a is pivotally mounted about a pivot axis Y, Y '. The movement of the winding mass is transmitted to a ring gear 12 by a system of two pawls. This ring is connected to the ratchet 14 of a barrel 20 by mobiles 16 and 18. The barrel 20 is connected to a timer mobile 24 by a mobile 22. The timer mobile 24 meshes on the one hand with a roadway 26 and on the other hand with a barrel wheel 28. The mobile 24 timer also meshes with a finishing train consisting of the mobile 32, 34, 36 and 38 mounted pivoting on the

  lower bridge 100. The escape wheel 38 co-operates with

  with the anchor-balance-spiral assembly bearing the

  30. Finally, the watch includes a set 110

key clocking mantle.

  The operation of the watch, outside the phases of setting time is as follows. The pivoting of the winding mass 10 under the effect of the movements of the watch rotates, always in the same direction, the ring gear 12 which thus causes the winding of the mainspring. The barrel, through the

  mobile 22 and the timer mobile 24, causes the rotation

  The French patent application No. 8419735, filed today in the name of the Applicant for "self-winding watch", describes in more detail the needles carried by the wheel 28 and the roadway 26.

the watch.

  Figures 2 to 4 show a first embodiment of the winding key 110. As shown in Figure 3, the key 110 comprises a cylinder 112 which passes through the bottom 6 of the box and which is pivotally mounted

  in a tube 114 forming an integral part of the bottom 6.

  At its outer end, the cylinder 112 comprises a

  lette 116 pivotally mounted about an axis X1, X1 'per-

  pendicular to the axis Y1, Yi 'of the cylinder 112. To its ex-

  internal triteness, that is to say at its end which penetrates

  In the watch case, the cylinder 112 is provided with a toothed wheel 118 whose axis coincides with the axis -6-. The pallet 116 has, for example, the shape of an isoclal zriangle. dont.e som-and is extended by two

  arm 1 and 120 '. The arms 120 e: 12J 'are provided with all

  cylindrical rillons 122 and 1 ^ 2 '. The cylinder 112 has an axial bore 2a. In addition, the outer end of the cylinder 112 is provided with two notches 112b and 112'b arranged along the axis X1, X '. The pins 122 and 122 'are engaged in the notches 12b and 112b. JUn tenon

  124 is driven into the outer end of the bore 112a.

  The head 112a of the post 124 closes the notches 112b and 112'b.

  The journals 122 and 122 'are thus imprisoned in

  notches 122 and 122 '. Pallet 116 can rotate around

  turn of lax X1, X '. In addition, the d-ame.tre body 124b of the pin 124 is sufficient for the ends of the trunnions 122 and 122 'enclose the body 124b of the

  in such a way that the pallet 116 can not turn

  around the Xt axis, X1 only when an external force

  it's applied to him. In addition, the outer face 6a of the

  bottom 6 of the box is provided with a housing 126 which feels

  the shape of the pallet 116. In addition, the

  The melter of this housing 126 is substantially equal to the thickness of the pallet 116. Thus, when the pallet 116 is folded, that is to say when the pallet is placed in the housing 126, it does not protrude out of the outer face 6a of the bottom 6. Of course, it is the same for the head 124a of the pin 124. This is of course the rest position. On the contrary, when the pallet 116 is raised in the direction of the Y axis, Y 'is largely protruding out of the outer face 6a of the bottom. It is then easy to hold it with the end of the fingers to subject the cylinder 112

  a rotation about its axis v, Y1 '. This is the posi-

1 'Yi'

active palette.

  It should be added that the dwelling 126 that feels

  siablement the same shape as the pallet 116, ensures accurate angular positioning of the cylinder 112 by

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  In its axis, the first and second pillars

engaged in lozemenz 126.

  The tooth wheel is mounted on the outer edge in

  dull cylinder 112 of the next market. The extrê-

  miré cylinder 112 has two notches forming two

  me2Dmats oaralelèes 112c and 112 'c. Symmetrically, the

  The axial shaft 113a of the wheel 118 has two studs 113b and 118'b. These plates 1135 and 118'b cooperate with the m4pDlats 112c and 112'c of the cylinder to fasten in rotation the cylinder 112 and the wheel 118. The wheel 118 is fixed on the cylinder 112 by a pin 129 driven or screwed into the bore axial 112a of the cylinder. It is clear that when the pallet 116 is raised, it is possible to control the rotation of the gear wheel 118 around

  the axis Y1, Y1 ', the cylinder 112 being substantially immo-

  translational in the direction Y1, Y1 '

  As shown in FIG.

  grene with the mobile 22, which also plays the role of forwarding time setting. However, wheel 118 is

  toothless on a fraction of its periphery cor-

  corresponding to a notch 118c. It should be observed that this notch 118c is opposite the mobile 22 only when the cylinder 112 has an orientation such that the pallet 116 can actually be introduced into the housing

  126. This possibility exists only for a single posi-

  auguration of the cylinder 112 because the arms 120

  and 120 'have inclined portions 120a, i20'a cor-

  corresponding to the thickness of the head 124a of the post 124.

  Figure 6 shows the kinematics of the mobile train allowing the setting of the needles from

  the rotation of the wheel 118. The mobile 22 is

  killed by two wheels 22a and 22b. The wheel 22a is secured to its axis, while the wheel 22b is mounted idly on this axis. A friction system F is interposed between the wheels 22a and 22b. The timer wheel 24 comprises a wheel 98 and a pinion 96 which are integral with the axis of the mobile, while a second wheel 130 is mounted -8 - mad on the axis. The wheel 130 is connected to the wheel 98 by a friction system F '. The time setting wheel 118

  meshes with the wheel 22a of the mobile 22. The wheel 22b

  grene with the barrel 20, while the wheel 22a meshes with the wheel 98 of the mobile 24 timer. Finally, the wheel 98 of this mobile meshes with the roadway 26, the wheel

  meshes with the first mobile 32 of the finishing train

  wise and the gear 96 meshes with the cannon wheel 28.

  During normal operation (without setting the time) the friction devices F and F 'respectively secure the wheels 22a and 22b on the one hand and the wheels 98 and 130 on the other hand. In addition, the bet wheel

  at time 118 does not mesh with the wheel 22a. The movement

  The cylinder is thus transmitted to the timer wheel 24 and the movement of the timer wheel to the finishing train. In the case of setting the time, the wheel 118

  meshes with the wheel 22a, but the resisting torque de-

  The barrel is sufficient to uncouple the wheels 2Za and 22b by removing the effect of the friction device. As a result, the rotation printed on the wheel 22a by the wheel 118 is not transmitted to the wheel 22b and the barrel is not actuated. Similarly, the wheel 22a meshes with the wheel 98, but the resistant torque developed by the finishing train is sufficient to uncouple the wheels 98 and 130 of the mobile timer

  24 by removing the effect of the friction device F '.

  Thus, the movement of the wheel 22a is not transmitted to the finishing mobile 32. Consequently, the action on the

  wheel 118 causes the needles to rotate through

  medium of the roadway 26 and the spur wheel 28, but it leaves still the barrel 20 and the system

exhaust 30.

  Figure 5 shows a possible way of achieving

  the mobile of the timer 24. This is mounted

  voting on an axis 92 driven on a post 90 making

  integral part of the bottom 6. The mobile 24 includes the pinion

  96 mounted on the shaft 92 via a bearing 94.

  The pig-no 96 comprises a peripheral toothing 96a and

  a shoulder 96b disposed below the toothing 96a.

  The first gear 98 is driven on the pinion 96 at the shoulder 96b. The second gear wheel is mounted idle on the body of the pinion 96 below the 98. The wheel 130 is held in position by a washer 132 driven into a second shoulder 96c of the pinion 96. The friction device F 'is interposed between the wheels 98 and 130. This is for example a

  a room with a large number of radial arms

  alternatively to the wheel 98 and to the wheel 130.

  The setting key 110 shown in FIGS. 2 to 4 is suitable if the time setting

  is made by rotating the wheel 118 by a number

  tier of turns. In this case, at the end of the

  on time, the notch 118c is found in front of the wheel 22a and the pinion 118 does not mesh with the wheel 22a. If the desired time setting accuracy is one minute, this means that a full turn of the pinion 118, it must correspond to a rotation of 1 / 60th of a turn of the roadway. Such a time setting system is ideally suited to correct the display error of the time due to the normal operation of the watch. On the other hand, a change of time zone of one hour would make it necessary to turn the time-setting key 110 by sixty turns, which risks being

  considered acceptable by some users.

  Therefore, Figures 7 show a variation

  the realization of the time setting key that overcomes this disadvantage. This variant comprises a cylinder 112 'similar to the cylinder 112 of Figure 3. At the outer end of the cylinder 112' is pivotally mounted the pallet 116 identical to that of Figures 2 and 4. At its other end, is mounted a first wheel 118 'secured to

  cylinder 112 '. It should be noted that the length 1 of the

  lindre 112 'between the pinion 118' and the axis X1, X 1'de the

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  pallet is greater than the length I 'of the tube 114. The cylinder 112' can therefore move in translation in the tube 114. A spring 134 has a shaped end.

  fork that enters a groove 112'd of the cylinder 112 '.

  Its other end is secured to the bottom 6. The spring

  134, at rest, tends to "raise" the cylinder 112 ', that is,

  ie to make it penetrate inside the box as shown in Figure 7a. The inner end of the cylinder 112 'extends beyond the pinion 118' and carries a second toothed pinion 136 secured to the cylinder

  112 '. The pinions 118 'and 136 have the same outside diameter

  laughing. The pinion 136 is provided with teeth regularly adjusted

  parts all over its periphery. The pinion 118 'has, him, a reduced number of teeth, the rest of its periphery constituting the analog of the notch 118c of the pinion 118

  of Figure 4. The number of teeth on this pinion corresponds to

  to a rotation of the roadway 26 giving the displacement

  unity of the minute hand, for example,

  one minute. When the spring 134 is at rest, the spring

  118 'is opposite the wheel 22a of the mobile 22. If the cylinder 112' is pulled down by means of the pivoting pallet 116, the pinion 136 comes in front of the wheel 22a and meshes with the this. This is shown in Figure 7b. The teeth of the pinion 136 must of course be cut to allow meshing with the wheel 22a during the translation of the cylinder 112 '. Let n be the number

  sprocket teeth 118 'and N the number of teeth of the sprocket.

  136. It is clear that if a turn of pinion 118 '

  a rotation of the minute hand corresponding to

  At one minute, a turn of the pinion 136 will correspond to a rotation of the hands of N / n minutes. The pinion 136 therefore allows a faster time setting when the correction to be made to the position of the points is important.

  The operation of this variant of the

  tif time is clear from the description

  former. At rest, the pallet 116 'is folded in its housing 126 identical to that which is shown here

  in FIG. 2 and the cylinder 112 'being recalled in po-

  high position, the toothless part of the pinion 118 '

  faces the wheel 22a. The pinion is maintained in this

  the position by the cooperation of the pallet 116 folded with its housing 126. If it wants to correct an error of a few minutes, the user raises the pallet 116 and, without exerting traction on the cylinder 112 ', turns

  this one with a number of turns corresponding to the correct

  desired. Then he puts back the palette 116 '

  in his dwelling. This is shown in Figure 7a.

  If the user wants to make a more im-

  carrying, it exerts a traction on the cylinder 112 ', which brings the pinion 136 in front of the wheel 22a, and, all

  by maintaining this traction, he turns the cylinder

  dre 112 'until he gets the desired correction.

  This is shown in Figure 7b. Then he rela-

  the traction and restores the pallet 116 in its housing 126. It should be noted that this second

  use of the time-setting mechanism is only

  because it corresponds to a change of

  time zone o when the watch is restarted.

  A third embodiment of the time-setting key is shown in FIGS.

  8b. This embodiment makes it possible to set the time

  whatever the movement of the needles,

  but, as in the first embodiment

  2 to 4, the key comprises only one toothed wheel. In fact, the first and third embodiments are very close to each other; this is why, in Figures 8a and 8b, the references

  already existing parts in the first mode of

  have been taken over without change. The cylinder 112 "has a length which is greater than that of the tube 114 in

  which he can slide. The inner end of the cy-

  lindre 112 "comprises the toothed wheel 118 identical to that of FIGS. 2 to 4, that is to say that it comprises

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  teeth regularly distributed on its periphery to the ex-

  ception of a zone devoid of teeth forming a notch.

  The outer end of the cylinder 112 "is provided with a

  The pivoting lug 116 is identical to that shown in FIGS. 2 and 4. When the pallet 116 is inserted into its housing, the notch of the wheel 118 faces the wheel 22a. There is therefore no meshing between the wheels 118 and 22a for this position. The difference with the first embodiment lies in the fact that the time setting key can take two positions

  in the direction of its axis Y1, Y1 '. For this purpose a

  same type of FIG. 7 has a first end which is integral with the bottom 6 and a second fork-shaped end which engages in a groove

  112 "d in the cylinder 112". At rest, the

  spell 134 holds the key in the "retracted" position as shown in FIG. 8a. In this position, the wheel 118 is in the same plane as the wheel 22a. Yes

  traction is exerted on the key by means of the

  lette 116, the key comes in the "exit" position

  shown in Figure 8b. In this position, the wheel 118 is no longer in front of the wheel 22a. The wheel 118 can therefore rotate freely without driving the wheel 22a. In this embodiment, the number of teeth of the wheel 118 and the mobiles 22, 24, 26 and 28 is such that a turn of the pinion 118 causes a sufficient advance of the needles to ensure a time reset after a number of

  turns down the time setting key.

  The operation of this embodiment de-

  clearly flows from the foregoing description. The utili-

  --ateur releases the pallet 116 from its housing 126 and the

  not in active position. Without pulling on the cylinder 112 ", he turns the key with the help of the pallet

  until the hands occupy the desired position.

  Then, the user pulls on the cylinder 112 "and, while maintaining this traction, it turns the cylinder until the pallet 116 is brought into

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  the posikion where it can enter housing 126.

  Then the user releases the pallet 116, which brings the notch of the pinion 118 in front of the wheel 22a. It remains only to fold the pallet in its housing 126, which keeps the notch of the wheel 118 opposite

of the wheel 22a.

  It appears that, whatever the mode of

  sation of the key considered, the palette 116 plays a dual role. On the one hand, when in the active position, it makes it possible to turn the wheel of time setting

  to perform the desired needle movement, from

  on the other hand, when placed in her dwelling, she

  used to identify the position of the key for which the

  check mark of the time setting wheel faces the wheel 22a and, moreover, it keeps the wheel in this position regardless of the shocks applied to the watch, which prevents an unwanted blocking of operation

of the watch.

  The foregoing description referred to a

  self-winding and self-winding watch

* guilles. This is indeed the primary area of application

  the mechanical device of time-setting, ob-

  jet of the invention. However, the application of this

  positive is not limited to this type of watch. The key can perfectly be used in a mechanical watch with disc display, only the wheels of

  time setting may be different. It can also

  be used in an electronic watch o, as is well known, the barrel is replaced by a

  stepper motor and the exhaust is removed.

  It follows from the description that the device

  setting the time actually helps to achieve the desired goals. In particular, it should be noted that, outside of the set-time phases, the time-setting key is entirely charged to the bottom of the box and that, on the other hand, when the pallet is out of its housing, it constitutes a sufficient hold for that

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  the user of the watch will do so. the

reset on time.

  It should also be emphasized that in the two

  xth and third embodiments, the amlitude of the translation is reduced, which makes it possible to mount it in a watch of reduced thickness. In addition, in these same cases, the spring 134 is solicited only

  for very good times and a number of times

  duit, which limits the efforts that are applied to it.

  Finally, there is no machining in the guide tube of the cylinder 112, 112 'or 112 ", which makes this

  solution compatible with a watch of very low

  thickness, for example less than 2 ma.

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Claims (5)

  1. mechanical device for setting a watch with a box provided with a bottom, analog display means of the hour, motor means and a train of mobiles for transmitting the movement of the motor means to means for displaying the time, said device being characterized in that it comprises a winding key (110) and means for returning the   the time (22) connecting said key (110) to said train of moduli   biles (23,26,28), said key comprising: - a rod (112,112 ', 112' ') pivotally mounted about its axis in the box bottom (6) and having a   inner end opening into said box and an outer   external tremity; a first toothed wheel (118) secured to   the inner end of said rod (112, 112 ', 112' "),   said wheel (118) having teeth on a portion of its periphery for meshing with said return means (22) and a notch (118c) on the remainder of the periphery:   a pallet (116) pivotally mounted at the end   outer half of said rod (112) about an axis (X1, X1 ') perpendicular to the axis (Y1, Y1') of said rod, the outer face (6a) of said bottom being provided with a housing (12b ) for said pallet (116), said pallet being able to assume a first active position in which it protrudes out of the bottom of said box and a second position in   which it is immobilized in rotation by said lodge   (126) for keeping said first wheel (118) in rotation, said notch (118c) being located to face said mobile (22) when said pallet (116) is in said housing (126).   2. Device according to claim 1, characterized   characterized in that said bottom (6) comprises, within the   housing, a guide tube (114) of said rod (112),   said rod being substantially immobilized in translation in said tube. - 16 -   3. Device according to claim 1, characterized   characterized in that said bottom (6) comprises, inside said housing, a guide tube (114) of said rod, in that said rod (112 '") is movable in translation, and in that said device further comprises a resilient member (134) for holding said first wheel (118) opposite said time setting return means (22), when said resilient member (134) is at rest and for disengaging said wheel (118); ) of said return means when   said elastic element is not at rest.   4. Device according to claim 1, characterized   characterized in that said bottom (6) has, inside said housing, a guide tube (114) of said rod (112); in that said rod is movable in translation; and in that said device further comprises a second wheel   (136) secured to said rod (112 ') and provided on the   tality of its perimeter of regularly spaced teeth and an elastic member (134) for holding said first wheel (118 ') in front of said return means (22) for setting the time, when said elastic member (134) is at rest and for causing said second wheel (136) to engage   with said return means (22) for setting the time when   that said elastic element (134) is not at rest under the effect of a force applied to said rod (112 ') for   translating said rod.   S. Device according to any one of the   3 and 4, characterized in that said elastic element   tick (134) is a leaf spring whose one end is integral with the inner face of said bottom (6) and whose other ectrémité has the shape of a fork which is engaged in a groove (112'd, 112 ' 'd) formed in said rod (112', 112 ').   6. Device according to any one of the   1 to 5 for a watch in which the display means comprise a gun wheel and a roadway and which comprises a finishing train, characterized in that - 17 -   said return means comprise a first mobile (22) constituted by two toothed wheels (22a, 22b) interconnected by a friction device (F), the first wheel (22a) being able to mesh with the ignition key; time (110), and a second mobile (24) comprising a   pinion (96) and a first wheel (98) integral in rotation   a second wheel (30) connected in rotation to the first   mière (98) by a friction device (F '), the pinion (96) of said second mobile meshing with said barrel wheel (28), said first wheel (22a) of the first mobile and with the roadway (26), said second wheel (130) of the second mobile meshing with the finishing train (32)