FR2704586A3 - Mechanism for moving a stepped floor of a movable terrace - Google Patents

Abstract

This comprises a pair of trains of pinions mounted on a pair of side walls (2d, 3d) close to the rear end of the first step (2, 3). Each train comprises one controlled pinion and two guide pinions (8, 9), a shaft (10) on which the controlled pinion (11) is mounted so as rotate with it and two chains (12) extending parallel with each other and [each] having one end (12a) attached to either end, right or left, of a riser (3b, 4b) belonging to the second step (3, 4), while the other end of the chains are attached to the opposite ends of the rear wall (3c) of the second step (3, 4).

Description

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  Movement device of a step pliancher

  D j..spo s _ j._t.jf d ___. M .......... e ...... e ........._....... ......at. ... e ................ r ....

  The invention relates to a device for movement of a tiered floor of a movable tier, in which a plurality of tiered floors can be

  retracted telescopically.

  A mobile bleacher intended for a hall with multiple use and the like is already known, in which a plurality of landing floors are retracted or brought back successively, below the adjacent rear landing floors, when the latter are not used, but, when used, they are deployed forward, giving a staircase configuration, and then folded armchairs located on each of the floor support surfaces are pulled to complete the

bleacher for its use.

  A mechanism for moving floors of this telescopic type bearings is described, for example, in Japanese patent application No. 61-121000, entitled "movable step" and filed by the applicant of this patent application. The

  mechanism is shown in figure 5.

  Referring to Figure 5, the mechanism includes a cable (c) having a front end attached to the most forward located floor (a) and a rear end, attached to and wound on a drum (b). When the cable (c) is wound on the drum (b), the landing floors are brought back successively into the rear seat floor (d). On the contrary, in order to deploy the landing floors in front, to obtain a staircase configuration, another cable (g) is wound on the drum (b). The cable (g) has a front end attached to the floor at. front bearings (a) and one rear end

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  fixed and wound around the drum (b) and extending over a plurality of fixed pulleys (e) and (f) mounted on the rear parts of the tiered floors and on lower surfaces of the various adjacent rear tiered floors. Each of the level floors is moved on the ground (i) by a plurality of wheels (h), and the opposite faces of the rear part of each of the level floors are guided by the adjacent level floor. As a result, there is the drawback that stepped floors are liable to

  move in a zig-zag when extended.

  To overcome this drawback, there is provided a device for parallel guidance of a mobile step, of the telescopic type, in which a pair of left and right gears are meshed on racks and rotated at the same speed, to move each. different level floors, in a rectilinear direction. Such a device is described, for example, in the Japanese utility model published under the

n 61-127255.

  With the parallel guiding apparatus, however, one cannot obtain a reliable meshing between the racks and the gears, because a step is normally composed of a large number of rods assembled by welding or the like and that consequently of the tolerance variations and other distortions of the chassis cannot be eliminated. The object of the present invention is to provide a device for a movable step, which can ensure a rectilinear movement forward of a tiered floor, relative to another tiered floor of the movable tier, when the latter floor is bearings

is moved.

  To achieve this object, there is proposed, according to the invention, a device for the rectilinear movement of a bearing with respect to another bearing belonging to a set of movable steps, in which the first bearing and the second bearing are associated. one to the other in such a way that, when the set of movable steps is not in use,

  the first bearing is brought down telescopically to the

  below the second landing, but when said set of steps must be put in the position of use, the first landing is pulled outside the second landing and it is put in the position of extension towards the front by achieving a staircase configuration, characterized in that it comprises a pair of pinion trains mounted on a pair of respective right and left side walls, adjacent to the rear end of the first bearing and each train comprises a servo pinion and a pair of guide pinions, a connecting shaft on which said slave bearings are mounted for their integral rotation, and a pair of chains extending substantially along parallel paths between them and having one end secured respectively to the opposite right and left ends of a riser belonging to the second bearing and the ends of said chains being integral with the opposite ends respectively right and left of the rear wall of the second bearing, said chains extending around and between the slave pinion and the guide pinions of the pinion train of the first

landing.

  With the device, the first tiered floor is guided in a parallel relationship by the right and left chains, as it moves relative to the last tiered floor. Correspondingly, when moving the first tiered floor, it can move forward or backward in a straight line, without being subjected to an oscillation to the left or to the right, which will prevent any collision

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  stepped floors between them and ensure a

  smooth movement of the first level floor.

  When the movable step comprises three or more tiered floors, the device according to the present invention can be placed between each of the

floors with adjacent landings.

  Preferably, in each of the gear trains, the servo gear is disposed below and between said guide sprockets and that of the chain associated therewith extends in a substantially S-shaped configuration along said servo gear and said sprockets guide. The device can thus be implemented even for floors with bearings which include a reinforcing frame mounted on the underside of their central part and which extends

  in the forward and backward direction.

  A specific embodiment of the present invention is described below in detail, at

  as an example, with reference to the accompanying drawings.

  Figure 1 is a plan view, partially in section, of a movable step in which is incorporated a floor movement device with bearings according to the present invention; Figure 2 is a vertical sectional view along the axis of Figure 1; Figure 3 is an enlarged sectional view showing the gear train shown in Figure 2; Figure 4 is a sectional view along line IV-IV of Figure 3; and Figure 5 is a schematic side view in

  elevation, showing a classic movable bleacher.

  Referring first to Figures i and 2, a movable step i is composed of a plurality of tiered floors, comprising a first tiered floor 2 or front floor, second and third tiered floors 3 and 4, located at back of

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  tiered floors 2 and 3, respectively, and a fourth tiered floor (not shown), or rear floor, located behind the third tiered floor 3. Each of the tiered floors 2, 3 and 4 is smaller width and height as the

  adjacent tiered floor behind it.

  The leveled floors 2, 3 and 4 are associated with each other, so that, when the movable step 1 is not used, the leveled floors 2, 3 and 4 are brought back successively, telescopically, to the - below the rear tiered floor, but when the movable tier i is to be used, the tiered floors 2, 3 and 4 are deployed forward, giving a staircase configuration. The floors with bearings 2, 3 and 4 are driven to move with the aid of means

  drive (not shown).

  The mechanism used to move the leveled floors 2, 3 and 4 can be of construction similar to the mechanism shown in Figure 5. From

  corresponding description of the mechanism

  is not made here to avoid redundancy, and only a floor-to-floor movement mechanism

  according to the invention is described below.

  The forwardmost tiered floor 2 has a box-like configuration which is open at the bottom and includes a base plate 2a, a pair of front and rear plates 2b and 2c which extend downward from opposite front and rear edges of the base plate 2a, and a pair of left and right side plates 2d which extend down from the opposite side edges

  left and right of the base plate 2a.

  Similarly, the second tiered floor 3 comprises a base plate 3a and a pair of front and rear plates 3b and 3c and a pair of side plates 3d which extend downwards,

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  starting from the base plate 3a, while the third tiered floor 4 comprises a base plate 4a and a pair of front and rear plates 4b and 4c and a pair of side plates 4d extending downwards, starting from the base plate 4a. Each of the first and second tiered floors 2 and 3 comprises a pair of vertical left and right mounting plates 5, provided on and extending towards the rear of the upper parts of the

  opposite side edges of their backplate 2c or 3c.

  Referring also to Figures 3 and 4, a pair of shafts 6 and 7 are mounted in a predetermined spaced relationship, at locations near the upper edge of the interior face of each of the mounting plates 5. A pair of sprockets guide 8 and 9 is supported for rotation on the

trees 6 and 7, respectively.

  A horizontal connecting shaft 10 is rotatably supported on, and extends between a pair of bearings

  10a, mounted in locations between and above

  below the guide pinions 8 and 9, on the opposite right and left mounting plates 5 of each of the tiered floors 2 and 3. A pair of slave pinions 11 is mounted to rotate integrally in locations near the left ends and

  opposite right side of the connecting shaft 10.

  In Figure 3, a left roller chain 12 is shown. The roller chain 12 represents has a front end part 12a, fixed to a lower part to the left of the rear face of the front plate 3b of the bearing floor 3. An intermediate part 12b of the roller chain 12 s' extends in a substantially inverted Q shape when viewed in side elevation view, around and between the guide pinion 8, the slave pinion 11 and the guide pinion 9, and a rear end portion of the

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  roller chain 12 is attached to a front surface of the

  back plate 3c of the leveling floor 3.

  Referring to Figures 1 and 2, a right roller chain 13 is arranged in symmetrical relation to the left roller chain 12 and thus has a rear end portion 13a, an intermediate portion 13b and a rear end portion re arranged in a way analogous to what it is for the

left roller chain.

  A similar mechanism is provided for the second bearing floor 3. In particular, a pair of pinion trains, comprising a pair of pinions 8 and 9 and a slave pinion 11 is mounted on the left and right mounting plates 5 of the second floor with bearings 3, and a pair of left and right roller chains 12 and 13 is fixed, at their opposite ends, to the third bearing floor 4, extending parallel to each other along the gear train of the second floor with bearings 3. The slave gears 11 are mounted for rotation on a

connecting shaft 10.

  The operation of the stepped floor movement device is described below in

  serving, for example, with the leveling floor 2.

  When the movable step 1 is in the returned state, the floors with bearings 2, 3 and 4 are positioned in a vertical overlapping relationship, and the pinion trains located on the floors with bearings 2, 3 and 4 are also positioned in a relationship of

vertical overlap.

  When the leveled floor 2 is pulled out and moved forward using the mechanism, not shown, the left and right gear trains located on the leveled floor 2 are moved forward, while producing a stroke of the chains 12 and 13. In this case, given that the left and right pinions 11 rotate integrally with the connecting shaft

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  , the front end part of the tiered floor 2 is advanced rectilinearly, without oscillating in

  left or right direction.

  In an analogous manner, the tiered floor 3 is pulled outside and it is advanced in a rectilinear manner with respect to the adjacent tiered floor 4

square. the back.

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Claims (4)

  i - Device for the rectilinear movement of a bearing with respect to another bearing belonging to a set of movable steps, in which the first bearing and the second bearing are associated with each other in such a way that when the set of movable steps is not in use, the first level is brought telescopically below the second level, but when said set of levels is to be put in position of use, the first level is pulled outside the second level and it is put in the forward extension position by achieving a staircase configuration, characterized in that it comprises a pair of trains of   gables mounted on a pair of respective side walls   right and left (2d, 3d), near the rear end of the first landing (2, 3) and each train has a pinion gear (11) and a pair of guide pinions (8, 9), a shaft ( 10) on which said slave bearings (11) are mounted for their integral rotation, and a pair of chains (12, 13) extending substantially along parallel paths between them and having one end (12a) secured respectively to the ends opposite right and left of a riser (3b, 4, b) belonging to the second bearing (3, 4) and the other ends of said chains being integral with the opposite ends respectively right and left of the rear wall (3c, 4c) of the second bearing (3, 4), said chains (12, 13) extending around and between said slave pinion (11) and said guide pinions (8, 9) of said   gear train of the first bearing (2, 3). 2704586   2 - Apparatus according to claim 1, characterized in that, in each of the pinion trains, said servo pinion (11) is disposed below and between said guide pinions (8, 9) and that of the chains (12, 13) associated therewith extends in a substantially Q-shaped configuration along said pinion   servo (11) and said guide pinions (8, 9).   3 - Apparatus according to claim 1 or claim 2, characterized in that each of the chains (12, 13) is a roller chain.   4 - Apparatus according to one of the preceding claims,   characterized in that said pinion trains are mounted on a pair of right and left cheeks (5) respectively arranged and extending backwards from the upper parts of the opposite sides of the first bearings (2, 3).