CA2034201A1 - Actuator device for the displacement of a member, and sliding-leaf doors equipped therewith - Google Patents

Abstract

Abstract Company called: FAIVELEY TRANSPORT "Actuator device for the displacement of member, and sliding-leaf doors equipped therewith". (Invention of Jean-Jacques MORVAN) A pulley (37) is fixed to each end of a mobile apparatus (31) and moves therewith. Moreover, to return pulleys (44) having fixed axles form, together with the mobile pulleys (37), a conjugate double tackle in which a flexible strip (9) links the wheels of all the pulleys (37, 39, 44), this strap being equipped with a dog (7) for the displacement of a member (2). The actuator (4) comprises two adjacent chambers (23) containing the motive fluid, each delimited by a median partition (27) and the respective one of two pistons of the apparatus (31) connected by an axial rod (32) passing through the partition (27) in a sealing manner. Application to the displacement of a sliding leaf of a railroad vehicle coupled to the dog whose travel is twice that of the mobile apparatus (31), the penetration of the mobile pulleys into the body of the actuator making it possible for the latter to be positioned very close to the pistons and thus making it possible for the axial bulk of the device to be greatly reduced. See Figure 1.

Description

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1 -- , "Actuator device for_the displ~cement of a mem~er,~and sli~l~gc~ doq ~quipped therew _h."

The present invention relates to a de~i~e ~or the S di~placement of a ~en~ber, and in parlicul~r ~or the displacement of a sliding lea~ ~etween its open and - closed positions.
- ~he present invention likewise relates to doors havin~ ~ sliding leaf or leaves equipped wi~h su~h a device.
- - - In many applications, and in parti~ular in rail : - or roa~ t~an6port vehicles, it is necessary t~ open or -~ : -close a sliding door b~ a ~echanical means o-f small b~lk, bearing in ~ind the available space, by exe~ting a positive ~c~ion in order to ob~ain each of the configura-tions, this beln~ for rea~ons of safety in operation. In ~u~h appl~c~ions, i~ is desired to avoi~ xotary motors, in par-t~cu~r ele~triG motors, in favor of actua~ors, in ' part~ cular hydraulic or pneumatic actuators.
- 20 A device is known which is re~erred to as ~
- "rodless actuator'~, in which a flexible strap, passing around two return p~lleys git~ated at the two ends o~ the body of a double-acting actua~or, is fixed by its two - . ~ ends to ~he two ends of the piston of the actuator. A
2S traveler mo~ing along the bod~ of the actu~tor is fixed - to the strap between the two pulleys and trans~its the motion to the memb~r to be displac~d. Rodless act~lators have the advantage of ha~ing a ~elatively lon~ useful ~ravel r~lative to their lengthwise bulk.
30 Ne~ertheless, the travel is still substantially less than the lengthwise ~ulk whereas, in the above-mentioned- applications rela~ing to vehiclçs, it ig - generally d~sirable ~or ~he motive device to be accom.
modated in the width of the aperture an~ ~o impar~ to the 35 leaf a travel subs~a~ially equal to said width.
. - Moreo~er) rodless ac~uator~ are cos~ly an~ pose ~ ~ifficu~t sealing pro~lems lia~l~ to entail maintenance -- :opqr~tions and breakdo~ns.
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A doubl~-acting actuator has likewise been proposed whose pis~on bears a rack enga~in~ with a pinion having its axl~ solidly ~ixed to the axle of a drive pulley of laryer diameter. ~he pulley driv~s a belt connected to the lea~. An appropriate ~iametral ratio between pinion and pulley make~ it possible to u~e conventional actuator of ~elatively small s.ize compatible with ~he available spa~e, while achieving sufficient amplitude of displacement o~ the me~ber to be ~ontrolled.
Such a devicQ, howe~er, suf~ers fxom a double disad~antage in that, fi~stly, it requires a relatively ~ostly rack-and-pinion syste~, ~nd secondly the drive pulley m~y slip ~ela~ive to the ~elt an~ consequently fail to transmit thereto the mo~ion created by the a~uator, It is thus necessary to make special arrange-~ent~ to avoid the abovementioned ~lippage, but with no certainty of preventinq ~he lat~e~, which may be in~on-venient ~o~ the point o~ view o~ safe~y in publi~
transport.
This device ha~ the further disadvanta~e ~hat, when ~he ro~ of the a~tuator is in the projecting pos~-tion, the rack passes beyond the drive p~lley, which means that here again a lengthwise bulk has to be pxovid~
ed which is ~early g~ea~er than the useful txavel of the de~ice.
Furt~ermore, F~-A-2,522,081 proposes in Figu~e S
a double~actin~ actuator ~aving a fixed apparat~s and a mobile apparatus, the lat~er aGtuating a flexible strap passing around two retu~n pulleys at the two ends of the ~vel Of a dog fixed to the st~ap in a re~ion extendin~
be~w~en khe two pulle~æ, said strap passinçl through two tackle devices each o~ which is functionally arranged bet~een one of the return pul leys and a respe~tiYe at~achment end, these tackle devices each comprising a tackle pulley whose axle is connected ~o th~ mobile appar~tus of the actuator.
When the mobile apparatus moves, it entrains with it the two tackle pulleys, one of whi~h pulls ~ length of strap substan~ially equal to a multiple of the len~h of ':: ,, - :.
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the displacement o~ ~he ~obile apparatus ~by virtue of the ~ackle~, while the other tackle pulley relea~e~ the same ~ultiple length o~ ~tr~p.
There thus takes place, between the two return S pulleyst a displacement o~ th~ strap, anclcQn~equently of the dog, whlc~ is equal to ~ multiple of the tra~el of the mobile apparatus of the actuator. No slipping is possible, since the displacement of the strap is a necessa~y consequence of the relative displac~men~ of the axles of t~e ~arious pulleys of the device. ~or~overt ~nd for the same reasons, if the actuator i~ of the double-~c~ing t~pe, or is of the single-acting and spring-return type, the deviGe transmits ~he ac~ion of the actuator in both directions of mo~e~ent of its mobile apparatus.
The a~ove device makes it possible ~o avoid the sealing problems specific to ~he ~Irodless actuator~" but provides virtually no improvement in the matter of bulk, eithex rel~ive to the rodless actua~o.rs or even relative to the rack-type actuators, slnce it is necessary to ~0 provide for the cleardnce o~ the tackle p~lley at each end o~ the body of ~he actuator.
The ob~ect of the present invention i~ thus to provide a very simple, reliable, compact and economical d~vice for the displacement o~ a member.
~he present invention relates to ~ device for the d~splacement of a ~ember between two predet~rmined positions b~ means of an actuator having a fixed apparatus and a mobile app~ra~us, the latter actuating a flexible strap surroundin~ two return pulleys at the two ends of the travel of ~ dog ~ixed to ~he strap in a region extending be~ween the two pulle~s, t~e said str~p passing throu~h two tackle de~ices, each of which is functionally arranged ~e~ween one of the return pulleys and a r~spective attachment end of t~e strap, these tackle devices ea~h comprising a tackle pull~y whose axle is connected to ~he mobile apparatus of the actuator, wh~rein the fixe~ apparatus of the actuat~r comprises a bo~y having two coaxial cylin~ers separated ~y a parti-~ion, and the mo~ile apparatus ~ompxises two pistons - . . . ............................ .

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~ach disposed in one of the cylinders, wherein at lea-~t one of the pistons defines, between itself and the partition, a variable-vol~e working chamber, the two pistons being conne~ted to each o~her by a rod pas~ing S through the partition in a sealing manner, each o~ the tackle pulleys being connected to a face of a respective piston, which face is opposi~e the partition, and where-in, at each end o~ the travel of the mobile app~xatus, one of ~he tack~e pulleys is engaged in the corresponding cyli~der.
By ~omparison with known devices, the device according to the invention possesses sub~tantial advantages, and in particula~ a very significant reduc-tion in longitudinal bulk, be~ause;
- the mobile apparatus, bearing on t~o pistons, is perfectly g~ided by virtue of its structure and in its positions alon~ the fixed apparatus, and pistons o~
a roduced axial dimension ~y be used without riskin~ any ~ilting and jammin~ effect:
- the penetxation of the t~ckle pull~ys into the body of the actuator, at the end o~ travel, a~lows the pulleys to be pl~ced very close to the piston~ and thus allows the axial hulk of t~e device to be g~ea~l~ reduced relative to that o~ FR-A-2,522,081.
According to a pa~ticular e~bodi~ent o~ the invention, the device is a de~ice comprising at leas~
four return pulleys, around which the strap describes a tra~e~tory corresponding to a closed loop supplemented by a half~loop so tha~, in any posi~ion of the mobile apparatus, the~e are two strands moving in the s~me di~ection and connected b~ a strand ~oving in the opposi-te dire~tion, and wherein a do~ is provid~d on each of the two strands of the loop.
~ccor~ing to a second aspect of ~he in~ention, the sliding-leaf dQor is a door wherein the l~af is connected to the dog of a device in ac~ordance wi~h the fir~t aspect.
Accordiny to a third aspect of the invention, the door ha~ing two lea~es sli~in~ in opposi~e ~irections i~

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a door wherein each leaf is connected ~o one of the dogs of the abovementione~ particular emb~dimen~ o~ the de~ice accoxding to th~ invention.
Oth0r features and advantages oi' the invention will become apparent in the cour~e of the description of ~ariou~ examples o~ embodiment ~hich will now be ~iven in a nonllmiting manner.
~ n the attached drawings:
- Fig~re 1 is a diagran~atic elevation of a sliding-lea~ door of a railroad vehicle fitted with a device a~cording to the inven~ion, shown with cu~ away and in par~ial section, the door being in th~ closed position;
- ~igure 2 is ~ diagrammatic view in longitudinal se~tion, on a larger scale, of the device in Figure l;
- Figure 3 is a view analogous to Fig~re 2, but shown in a position corresponding to the open position o~
th~ door - Figure 4 is a pa~tlal section ~f an al~ernative en~odim~n~ comprising~ for e~h tackle de~ice, a second tackle pulley pern~i~ting greater amplification oE
~otion;
- Figure 5 is a ~iagran~atic section of anotheL
alte~native embodiment of the device according to ~he invention, ~ith a partial view of a door having two leaves sliding in the opposite direction.
A de~ice 1 according to the invention is shown in Fi~ures 1 to 3. T~e device 1 is installed above the sliding leaf 2 o~ a door 3 givin~ ~ccess to a railroad vehicle, in order to aotu~te this leaf, b~ mean~ o a double-acting actua~o~ 4, between a position of closu~e of a passage surrounded by the frame o~ the doo~ 3 an~ a position o opening o~ thi~ passage.
The door ~ is a doo~ having a single sliding leaf, o~ a t~pe known per se, which it is unnecessa~y ~O
describe in detail. In the upper part of the door, in the ~icinity o~ the lea~ing ed~e (~elative to ~he direction of closure)~ is fi~ed a bxacket 5 provided wi~h a s~ating ~o r~ceive ~he end o~ ~ do~ 7, the bracke~ S and the dog 7 being solidly fixed to each other relative to move-ments which are parallel ;

~~ 2 03f~2 to that of the leaf 2. ~he do~ 7 is fixed at an appro~
priate point of an actuation region 'la of ~ ~lexible strap 9. In the ~egion 9a, the strap ~ moves in ;it~ own lQnyth by th~ func~ioning of the device 1 and may adopt S two positions 7a, 7b, respectlvely corresponding to the closu~e and ~o the opening of ~he leaf 2 ~s~e Figu~es 2 and 3). In the example shown, the door is of the type having a simply sliding leaf (~hat is to say tha~ the leaf mo~es in it~ own plane) but t~e invention is llkewise applicabl~ ~o doors having a leaf of the so-ca~led com~lned type, in which the leaf undergoes, at the ~tart of the opening movement and at the end o~
the closing movement, an ex~r~c~ion move~nt an~ an insertion movemen~, respe~tively, relative to the ~ram~
o~ the door. In thi~ case the dog 7, instead ~ being coupled directly to the leaf, would for ex~mple ~e couplod to a trolley, rela-tive to ~hic~ the leaf executes its movements of, re~pecti~el~, extraction and inser~ion.
In ~he example shown in.Pi~ure 1, the ~uide means or the lea~, which may for example comprise rollers fixed to the leaf and sliding in rails solidly fixed to the frame of the door, ha~e been omi~ted, the device according to the invention providiny only the ~riving and not the ~uiding oE the leaf.
A fixed apparatus 11 o the double^-~cting act~tor 4 co~prises a body 1~ fixed to the ~ame of the doo~ 3 by means of assemblies 19, 21 forming collars.
~he body }3 ~e~ines within itself two cylinde~s lS (soe ~igure 2) wh1~h hav~ the same axi~, parallel tO
the di~e~ion of ~he .sl~din~ of ~he leaf, and the same diameter and are ~eparate~ in a sealing manner by a fixed median partition 27. In each cylinder 15, a ~ariable-volume cha~bex 23 is defined between the partition 27 an~
a respective piston 29 which is reciprocally movabl~ in t~e cylin~ex 15. The ~wo pistons ~9 and an axial rod 32 connecting ~he latter form a mobile apparatus 31 which moves as a single unit within the body 11 of ~he ac~uator 4. The rod 32 passes through the partition 27 in a sealing manner relative to the press~re difference ~hich .,, . ,, ' ~ , . .
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may exist, in operation, between the two chambe~ 23, as will be understood in due ~ourse. The chambers 23 ~ay be sclec~ively co~nected by lines 33 to a compressor 34 or to the atmosphere 35 by means of a distxibu~ox 30, in a ~anner such that one of the chambers 23 eva~uates to the atmosphere 35 when the other fills un~er the action of the compressor 34 Iwhich ~ay be a pressure ~ource of the vehicle) or conversely.
~he oute~ surfaces of the pi3tons :29 ~oppo~ite to the partition ~7) each hear a block 41 supportlng a tackle pulle~ 37. Under these conditions, the axle~ of the two pulleys 37 axe solidly fi~ed to the ~obi~e apparatus 31 of th~d actuator 4.
T~o return pulleys ~4 rotate a~out axle~ 49 which ar~ fixed relative to the fixed ap~aratus of the actuator, the two axles 49 being substantially parallel an~ situated, in operation, in a plane substan~ially p~rallol to th~ di~ec~ion of the sliding of the le~. The retu~n pulleys 44 are ~a~h s.ituated at one o~ the end~ of the device, beyond one of th~ respective ends of the body 13.
~he region 9a of the strap 9 extends between the two return p~lleys 44.
On either side of ~he region 9a, the strap 9 compri~es two tackle regions gb which each extend between the associated ~eturn pultey 44 and a r~spec~i~e attach-~ent end gc. E~ch tackl~ region ~b passes a~ound the nea~est tackle pulley 37, thus adopting a U-shap~d configuration openin~ towards the outside of the body 13.
The two ends 9c are i~ed to two lu~s 45 whi~h are fixed relative to the ixed appara~us ll o~ the actuator 4 and sit~ated subs~antially at the ends of the devi~e.
~he mo~e o~ operation of the de~ice is as follows:
3S ~t may be assumed that ~he door 2 is in the closed position, as shown in Figlres 1 and 2, and ~hat the dog 7 is in its seating situated in the brac~et 5, occupyin~ the position 7a (Figure 2). The ri~ht-hand pulley 37 is en~a~ed in the corresponding cylin~ex 15. To ~ - : - ., .
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~-- 2~3~2~1 open the leaf, the left-hand chamber 23 is connected to the compressor 34 and, simulkaneously~ the other cham~er 23 is connected to the a~mosphere 35.
Under these conditions, the volume o~ the fir~t chamber 23 increases, that is to say ~hat the mobile apparatu~ 31 of ~he act~ator ~oves toward the leSt i~
Figure 2. The right-hand pulley 37 moves away towar~ the interior o~ the bod~ 13, relative to the corresponding p~lley 44 and lug 45, this pulley 3~ penetra~ing into the adjacen~ c~llnder 15. ~h~ effec~ of this, foL each of the strand.~ 52 and S3 of the associated region 9b, is an increase in len~th which i~ substantially equal to the txavel performed by the mobile appar~us, and this absorpt.ion of s~rap by the right-hand tackle device thus lS has to be compen~ated by a displacement of the region 9a bearin~ the dog 7, this displacement ~eing equal ~ the sum of the increases in len~th of ~he strands 52 ~nd 53, thus e~ual to twice the travel performed by the mobile apparatus 11. This displacemen-t of the re~ion 9a in i~s 2Q own length to~ard the righ~-hand ~ackle device is permitted by the left-hand tackle device since each of the two strands of the reqion 9b are reduced in length by an amGunt su~stantially equal to the travel per~o~med by ~he mobile apparatus 31.
~5 Finally, the dog 7 passes from the position 7a to the position 7br shown in ~x4ken lines, correspondin~
to the opening of the door 2, with a distance L bet~een the initial and final positio~s of the dog 7 which is equ~l to twice the total d.L~placement of the mo~ile apparatus of the ac~uator, an~ substan~ial~y e~ual ~o ~he length of the body 13 of tho actuator 4.
In other words, the effect o~tained is an amplification of mo~ion by a factor of 2.
In or~er to pass fro~ the open position oP the ~eaf 2, w~ich is sho~n in Fi~ure 3, ~o the closed p~si-tion, an analogous but s~nmetrical pro~eduxe is adopted, ~hat is to say that the ri~ht-hand chamber 23 i5 conne~ted to the compressor 34 ~nd the left-han~ chambex to the atmosphere 3~. This causes the displacement o~ the ,. ~,. ~-, ... . . . .......................... . .
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_ 9 _ dog from the position 7b to the position 7~, and conse-quently the closure of the lea 2. Ry virtue o~ it~ two plstons 29, rigidly conne~ted ~o each other, the mobile apparatus 31 i~ very well guide~ within the body even if 5 the pi~ons are axially very-thin. This enables the axial length of the actuator to be further reduced.
In the alternative embodiment of th~ inven-tion ~o which Piguxe 4 ~elates, each tackle device comprise~ a second tackle pulley 39 having a fixed axle 43, around which tackle pulley the str~nd 9b passes between the ~obile tackle pulley 37 and the attachment end 9c which i~ directed toward the mobile apparatu~ and fi~ed to a hook S7 carried b~ ~he ~especti~e piston 2g alongside the block 41.
I~ will be understood -that, in this manner, any displacement of the mobile app~rat~s, for ~xample towaxd the left ~Figure 4), increases by an equivalen~ amount the length o~ each vf the thxee st~ands 61, 63, 65 o the right-hand region 9b and r~duces by an eguivalent amoun~
each of the thxee strand~ of the lef~-hand region ~b, so that the travel o~ the dog 7 is triple that of t~e mohile apparatus 31.
The above alternative embodiment ~akes it readily possible to obtain a displacement o~ the sliding lea~ 2 2S which is subtantiall~ gre~ter than the len~th of the associated a~tuator 4. Such an altexnative embodiment ma~
adv~ntageously be employed whene~er ~he availRble spa~e i~ stri~tly limited to the width of ~he doo~.
The alternative ernbodiment as shown diagr~mmatically in Figure 5 relates to a door havin~ two leaves sliding in opposite di~e~tions, the po~ition shown corresponding to the opening of the two leaves.
The desc~ip~ion ~ill be li~ited ~o an indi~ation of ~he di~erences as compared with ~he embodiment in ~i~u~e l.
T~e two single return pulley~ 44 in Fi~ures 1 to 3 are replaced by two dou~le pulleys 54 mounted on ~he fixed axle~ 49. The flexible s~rap ~ is guided over the pulleys 54 in a manner ~u~h that its region o fixed .
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qeometry comprises a supplementary loop 9e, 9f in addition to the half~loop ~a in Figuxe~ 1 to 3, the length of the s~rap 9 being increased a~ a conseque~ce.
The strand 9a moves, a~ previou~ly, ;.n ~h~ opposite S direction to the mobile appa~atus, the strand 9f moves in the sam~ direction as the strand 9a, w:hile the return strand 9e move8 in the same direction as ~he mobile ~;
apparatus 31. . :
T~-o dogs 7 and 8 are provided, each fixed to one of ~he leaves. ~he dog 7 is, moreover, ~ixe~ ~o the strand 9a, as previously, while the dog 8 is flxe~ to the strand 9e. The references 7a and 8a de~ignate the posi-~ions of ~he dogs 7 and 8 when the leaves are open, and the references 7b and 8b desi~nate the positions of ~he lS dogs 7 and $ when the leaves are closed~ Fro~ thei~
re~pective leav~s, th~ dogs 7 and 8 are angled towards each other in a manner such that the respective ~ravels o~ th~ir poin~s of att~chmen~ ~o the strand~ 9a and 9e r ~espe~ti~ely, are superposed. In other words, ~he posi-~0 tions 7a and 7b of the dog 7 are ~ubstantially opposl~eto the po~itions 8b and 8a, respectively, oE the doq 8, which minimises the bulk of the device in th~ direction :
of the width of the opening.
Th~ mode of operation is identical to that in the . :~

2$ em~odiment o~ Figure 2, though with the difference ~hat, for a displacement d o~ the mobile appa~atus in a specific di~ection corresponding, for example, to the closing of the ~oor, the two panels move in opposite directions, each by 2d. In total, for the above displ~ce-men~ ~, the f~e~ passage closes by the distance ~.
~ he present inven~ion makes it possi~le toproduce an actuator-based device for displacing a member between two specific positions by a po~itive action in both directi~ns, this device having the ad~antage~ of being of reduced ~imensions, of simple construction and o~ reliable operation.
In pa~ticular, it is possible to install wi~hin a very limited space, such ~s that which may ~e aYailable in a collective mean~ of transport, a device for , :;, ., . :
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operating a ~liding door having a coefficient of amplifi-cation of the mo~ion of the piston of the actuator which is at least equal to ahou~ two, this device moreover being of very great relia~ility.
~he in~ention is not, o~ course, restricted to the examp].e~ of embodiment which have just been described, and numerous ~odiiications may be made ther~to without depar~ing ~rom the scop~ of the present invention.
Thu~, the number of ~ackle pulleys ~or each ~ackle device cou}d be greater than two, as a function of the diamete~ of the pis~ons and o~ ~he amplification of motion e~visaged.
~oxeover, the number of return pulleys eould be increased to take into account the ~elative disposition of the actuator and of the door, possibly impo~ed by cono~miny to the space availa~le.
~he ~tuator could posse~s a mobile body and a fixed pistvn, the body bearing, on an outer la~exal wall, two blocks for the two mobile tackle pulleys.
It would thus also be pos~ible to pro~ide for the actuator to be of a conventional type wi~h ~ixed body and mobile pistcn of the rod type, the ro~ bearing, outside the bod~, the two mobile tackle pulleys of ~he ~wo tackle devices.

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Claims (6)

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1. A device for the displacement of a member between two predetermined positions by means of an actuator (4) having a fixed apparatus (11) and a mobile apparatus (31), the latter actuating a flexible strap (9) passing around two return pulleys (44, 54) at the two ends of the travel of a dog (7, 8) fixed to the strap in a region (9a, 9e), extending between the two return pulleys (44, 54), the said strap (9) passing through two tackle devices (37, 45; 37, 39; 57), each of which is functionally arranged between one of the return pulleys (44, 54) and a respective attachment end (9c) of the strap (9), these tackle devices each comprising a tackle pulley (37) whose axle is connected to the mobile apparatus (31) of the actuator (4), wherein the fixed apparatus (11) of the actuator comprises a body (13) having two coaxial cylinders (15) separated by a partition (27), and the mobile apparatus (31) comprises two pistons (29) each disposed in one of the cylinders (15), wherein at least one of the pistons (29) defines, between itself and the partition, a variable-volume working chamber (23), the two pistons being connected to each other by a rod (32) passing through the partition (27) in a sealing manner, each of the tackle pulleys (37) being connected to a face of a respective piston (29), which face is opposite the partition (27), and wherein, at each end of the travel of the mobile apparatus (31), one of the tackle pulleys (37) is engaged in the corresponding cylinder (15).

2. The device is claimed in claim 1, wherein each tackle device comprises means (45) for fixing the corresponding attachment end (9c) of the strap (9) in a fixed position relative to the fixed apparatus (11) of the actuator (4).

3. The device as claimed in claim 1, wherein in each tackle device the strap passes, between the tackle pulley (37) and its attachment end (9c), around a second tackle pulley (39) having an axle (43) which is fixed relative to the fixed apparatus (11) of the actuator (4), and wherein each attachment end (9c) is fixed to the mobile apparatus (31) of the actuator (4).

4. The device as claimed in claim 1, wherein it comprises at least four return pulleys (54), around which the strap (9) describes a trajectory corresponding to a closed loop (9e, 9f) supplemented by a half-loop (9a) so that, in any position of the mobile apparatus (31), there are two strands (9a, 9f) moving in the same direction and connected by a strand (9e) moving in the opposite direc-tion, and wherein a dog (7, 8) is provide on each of the two strands of the loop.

5. A sliding-leaf door associated with a device as claimed in claim 1, wherein the leaf (2) is connected to the dog (7).

6. A door having two leaves sliding in opposite directions, wherein each leaf is connected to one of the dogs (7, 8) of a device as claimed in claim 4.