EP0679794B1 - Extension ladder operating device - Google Patents

Abstract

The device has a pivot (35) which is attached to the vehicle (1) by a rail (2) running lengthwise along the vehicle so that it forms an overhang over the rear of the vehicle. There is an attachment (7) joined to the vehicle beneath the pivot which provides a fastening in line vertically with the pivot. The ladder (5) is attached to a cradle (4) by its base section (50) so that the other sections can move freely in relation to the base section (50). The cradle is positioned between the two ends of the base section and can be attached to the pivot by a universal joint. The cradle is supported on a carriage (3). There is a device which can be adjusted in length (9) which forms a rigid joint between the bottom of the base section of the ladder (50) and the attachment. <IMAGE>

Description

The present invention relates to a device for sliding ladder operation, plus device particularly intended to be mounted on a vehicle able to carry such large scales dimension: utility trucks or vans, in particular of firefighters.

There are currently sliding ladders at three plans which, when fully developed, are long about seventeen meters, allowing to reach heights of at least fifteen meters above the ground. Given their longitudinal dimensions, they are most often worn on the roof of vehicles van type utilities. For transport, plans are immobilized between them by means of the rope of the development system, the whole being subject on the vehicle like a conventional load.

As a rule, no less than four people well-trained must combine their efforts to set up such a ladder which, despite it is made of light alloy tubes, does not weigh less than eighty kilograms or more. We can easily imagine the importance of the overhang of this equipment deployed seventeen meters high, and the importance of the restraint effort that must be provided to bring the top of the ladder to rest on a wall which will lie horizontally at almost six meters ground support. Under normal conditions, estimates that the average operation time is twenty minutes. But it's counting without conditions unfavorable such as strong wind or false maneuvers. In addition, it is not uncommon to ensure security, the ladder should be guyed, this which in addition to the time it takes may cause additional difficulties, such as requiring plant stakes in the roadway.

The present invention therefore consists of a device providing a global solution to this problem, in that it minimizes and therefore very clearly facilitate human intervention to maneuvering large sliding ladders, and in that it also allows an establishment much faster from these scales which is a of paramount importance in the context of the activities of firefighters.

• un pivot porté par le véhicule en porte-à-faux de manière à être dégagé à distance de la caisse du véhicule ;
• un moyen d'attache porté par le véhicule, à distance sous ledit pivot, pour établir une fixation en un point sensiblement sur la même verticale que ce dernier ;
• un berceau dans lequel est fixée l'échelle par l'intermédiaire de son plan de base, de telle manière que les autres plans de l'échelle puissent être manoeuvrés librement par rapport audit plan de base, lequel berceau se trouve en position intermédiaire entre les extrémités dudit plan de base, et comporte un moyen pour être reçu et assujetti sur ledit pivot selon une liaison à la Cardan ;

   et un moyen de longueur réglable pour établir une liaison rigide basse réglable en longueur entre la partie inférieure du plan de base de l'échelle et ledit moyen d'attache sous le pivot, liaison destinée à assurer la retenue et la stabilité de l'échelle, tant dans son plan transversal que dans son plan d'inclinaison.More specifically, the invention is a sliding ladder operating device which, mounted on a vehicle, comprises:

• a pivot carried by the vehicle overhanging so as to be released at a distance from the vehicle body;
• attachment means carried by the vehicle, at a distance under said pivot, for establishing a fixing at a point substantially on the same vertical as the latter;
• a cradle in which the ladder is fixed by means of its base plane, in such a way that the other planes of the ladder can be maneuvered freely relative to said base plane, which cradle is in an intermediate position between the ends of said base plane, and comprises means for being received and secured on said pivot in a connection to the gimbal;

and an adjustable length means for establishing a rigid rigid link adjustable in length between the lower part of the base plane of the ladder and said attachment means under the pivot, a link intended to ensure the retention and the stability of the ladder , both in its transverse plane and in its inclination plane.

Due to the connection to the Cardan joint of the cradle scale on said pivot integral with the vehicle, the cradle can be swiveled around a vertical axis on 180 ° to orient the scale, around a first axis horizontal transverse to tilt the scale, and around a second horizontal axis orthogonal to the first to adjust the transverse verticality of the scale.

The rigid low link of adjustable length advantageously comprises a stirrup fixed on the side and other from the base plane of the scale, for example at level of a bar, as well as a median arm telescopic with progressive locking means or brake to adjust its length.

In a preferred embodiment of the invention, said pivot is slidably mounted on a longitudinal rail fixed to the vehicle roof and protruding at the rear, so as to be movable in together with the ladder and its cradle between a rear service position and a front position of transport.

la Fig. 1 est une vue schématique de côté d'un dispositif selon l'invention monté sur un véhicule de pompier de type fourgon-pompe-tonne,

la Fig. 2 est une vue de côté, à échelle agrandie, du pivot et son montage dans le dispositif de la Fig. 1,

la Fig. 3 est une coupe selon la ligne III-III de la Fig.2,

les Figs. 4 et 5 sont respectivement une vue de côté et une vue de bout, également à échelle agrandie, du berceau d'échelle,

la Fig.6 est une vue en plan de la liaison rigide basse,

la Fig. 7 est une vue schématique en coupe transversale du moyen de fixation porté par le véhicule de ladite liaison rigide basse,

les Figs. 8 à 11 sont des vues schématiques illustrant le principe de fonctionnement du dispositif selon l'invention, et

la Fig. 12 est une vue de côté représentant de façon schématique une échelle maintenue en place contre une paroi au moyen d'un dispositif selon l'invention.

These characteristics and advantages of the invention, as well as others, will appear more clearly in the following description of an exemplary embodiment, made with reference to the appended drawings, in which:

Fig. 1 is a schematic side view of a device according to the invention mounted on a fire engine of the van-pump-ton type,

Fig. 2 is a side view, on an enlarged scale, of the pivot and its mounting in the device of FIG. 1,

Fig. 3 is a section along line III-III of FIG. 2,

Figs. 4 and 5 are respectively a side view and an end view, also on an enlarged scale, of the ladder cradle,

Fig.6 is a plan view of the lower rigid connection,

Fig. 7 is a schematic view in cross section of the fixing means carried by the vehicle of said low rigid connection,

Figs. 8 to 11 are schematic views illustrating the operating principle of the device according to the invention, and

Fig. 12 is a side view schematically showing a ladder held in place against a wall by means of a device according to the invention.

Throughout the drawings, the same signs of reference have been used to designate everywhere same elements.

Fig. 1 illustrates a device in accordance with the invention mounted on a fire truck 1. It this is a device intended not only for the maneuvering of a sliding ladder, but which serves also to place and secure it in position of transport on the vehicle roof 1.

The device includes a beam or rail metallic 2 mounted longitudinally on the roof of the vehicle 1, for example centrally. It exceeds the rear within the limits imposed by the regulations of road traffic. In practice, the part protruding is about one meter long. Yes necessary, it is provided with reinforcing arms 24, Fig. 1.

Rail 2, on which a carriage 3 is mounted, is advantageously an H profile whose core 20 is vertical, and which therefore has two lower wings and higher, respectively 21 and 22, as shown better Fig. 3.

The carriage 3 is mounted on the rail 2 so as to have only one degree of freedom sliding along of it, between the rear end E and a limit before limit switch L located on the roof of the vehicle 1, Fig. 1. In the example of realization shown, the body of the carriage 3 has a profile of U inverted to cover the rail: it has a horizontal upper shelf 30 and two walls vertical lateral 31. It is held in place and retained on rail 2 by two horizontal wings 32 internally directed from the side walls 31, which enclose therewith and the plate 30 the upper wing 22 of the rail 2. The carriage 3 rolls on the lower wing 21 of the rail 2 by means of two front and rear pairs of rollers 33.

At the rear end of rail 2, a rear stop 23 mounted between wings 21 and 22 limits the travel of the carriage 3 to the rear. On the other hand, a lock allows it to be locked in its most remote position. The lock shown in the drawings is a hook tilting 34 articulated around a transverse axis on the plate 30, which hangs by gravity around from the rear end of the rail 2.

The carriage 3 carries fixed on its plate 30 a tubular part or sleeve 35 of internal section circular, vertically oriented and open upwards. It is located substantially in the center of the plate 30.

The sliding ladder 5 which conventionally comprises three plans including a base plan 50, a plan intermediate 51 and an upper plane 52, is mounted in a cradle 4 appearing in more detail in Figs. 4 and 5 (for reasons of clarity of the drawing, the cradle 4 has been shown without the scale in FIG. 4).

The cradle 4 essentially has two sides 40 joined by lower crosspieces 41, to receive the scale 5 in such a way that the plans 51 and 52 remain maneuverable from the basic plane 50. To this end, as illustrated in FIG. 5, only the base plane 50 is fixed suspended across the upper part of cradle 4, the other two planes 51, 52 being suspended under him inside the cradle. In practice, in the case of a ladder classic with hollow rungs, the base plane 50 is fixed in cradle 4 at two levels, by through transverse rods 43 passed through through these steps and received and keyed in receiving holes 42 made in the upper part from each of the flanks 40.

The cradle 4 further comprises a transverse axis lower 44, Fig. 5, arranged substantially in sound middle, by which it is articulated on a part 6. This has a horizontal intermediate plate 60 on which is fixed by means of a mount 61 a vertical bearing 62 and under which is fixed a vertical cylindrical tail 63 of section circular. Axis 44 is engaged and retained at the level of its central part in the bearing 62. With respect to the part 6, it has a rotational ability on itself in bearing 62, and moreover, it has a certain oscillation ability all around a position normal to the plane of the mount 61. For this purpose, the bearing 62 is a spherical or equivalent bearing, by example a swing bearing. An means for limiting the oscillation of axis 44, this means being for example, as shown, a jumper 64 secured to the plate 60 and surrounding the axis 44 near the bearing 62.

The cylindrical tail 63 of the part 6 is intended to be received in the socket 35 of the carriage 3 previously described, in which it can spin freely. Possibly, a means of lock not shown is provided to maintain the tail 63 in place in the socket 35. The cradle 4 is then removably carried on the carriage 3 by a Cardan joint: it can pivot longitudinally around its transverse axis 44, pivot transversely due to the possibility of oscillation of the transverse axis 44 in the bearing 62, and turn around the axis of the socket 35.

The device of the invention further comprises, secured to the vehicle 1, an attachment means 7 which is located at a distance under the rear protruding part of the rail 2, carried on an arm parallel to it and in the same vertical plane. In practice, rail 2 being centrally disposed, the attachment means 7 can be carried on the rear drawbar 8 of vehicle 1. It thus finds at 50 cm above the ground, approximately, a vertical deviation of the order of 2 m separating it from rail 2 which is about 2.5 m away.

The attachment means 7, Figs. 1 and 7, includes a slide 70 mounted on a slide 80, which is located on the top of the drawbar 8, on all of its length. The slide 70 is provided with a brake, by example a screw 71, to allow it to be locked in one any point on slide 80, and, as that attachment element, of a cylindrical tail 72 directed upwards.

The attachment means 7 is intended to receive a end of a rigid link 9 articulated by its other end at the bottom of the amount of base 50 of scale 5, which rigid connection 9 has function to ensure the restraint and stability of the scale, both in its transverse plane and in its tilt plane.

The rigid connection 9 is shown in plan on the Fig. 9. It has as longitudinal median element a telescopic arm 90 adjustable in length by means a screw 91 ensuring the tightening between its two parts 90a, 90b. A metal structure is attached to the outer part 90b of the arm 90, which forms beyond from a first end of the latter a stirrup 92. The bracket 92 has a base cross member 93 and two branches 94 parallel to arm 90, between which plans 50 to 52 of scale 5 are received. Advantageously, the fixing is ensured by means of a transverse rod 95 passing through a bar of the base plan 50, and received and keyed in holes at the ends of the branches 94, the connection 9 possibly so rotate relative to the scale around the rod 95.

The second end of arm 90, the end free from part 90a, includes an attachment ring 96. It is a ball joint or equivalent for allow it to be engaged and keyed quickly and without difficulty on the vertical attachment tail 72 of the means 7, and to also allow the connection rigid 9 pivots freely around the attachment tail 72.

In Fig. 1, scale 5 in transport position on the roof of vehicle 1 has its two planes 51, 52 immobilized with respect to its basic plan 50 so classical, that is to say by means of the sound string development system. At the back, scale 5 protrudes slightly beyond rail 2, and the connection rigid 9 hanging under the ladder is immobilized by a quick release 98.

Beyond the cradle 4 towards the front of the vehicle, scale 5 is received in a support, advantageously formed of lateral uprights 100 and rollers 101 mounted crazy at the base of these uprights, on which supports plan 52 of the ladder. The amounts 100, which can be mounted integral with rail 2, have holes 102 at the base plane 50, to allow to subject the latter by commitment to through a rung of a transverse rod received in these holes and keyed.

A means of securing the cradle 4 can also be provided, consisting for example of lateral arms 103 pivotally mounted at their base, and coming to be fixed by their upper end on nipples protruding outwardly on the sides 40. On the other hand, the carriage 3 is against its stop forward limit switch on rail 2.

To place the ladder against a wall, the first operation is the responsibility of the vehicle driver 1 who is going to have to place the latter adequately by relative to the wall and depending on the height at achieve. Generally, vehicle 1 will be placed parallel to the wall, at a distance calculated so that the inclination of the ladder is correct.

Fig. 8 illustrates the next step by which ladder 5 descended to the rear of vehicle 1 after release of the rigid attachment 9 and the means securing in transport position, and retreating and locking in position E on rail 2 of carriage 3 loaded with cradle 4 and ladder 5. The cradle 4 and ladder 5 are then pivoted around axis 44 to descend the base of the ladder towards the ground. Note that the longitudinal position of the cradle along the ladder is such that the base of it cannot touch the ground. Then, the scale being standing upright close to the vertical, the link 9 is hooked by means of attachment 7.

In Fig. 9, scale 5 has been rotated 90 ° around the vertical axis of the socket 35 to be presented facing the wall. To adjust the verticality transverse of the scale 5, it was then necessary to move the slide 70 of the attachment means 7 on its slide 80 to place the attachment tail 72 and the socket 35 in the same vertical plane normal to the wall and therefore to the scale plan. From this position, the arm 90 of the rigid link 9 is reduced to its length minimum to draw the scale 5 most vertically possible, after which it is developed to the desired length. Then, to descend the ladder in support against the wall, the arm locking screw 91 is slightly loose. It acts thus in braking of the elongation of the arm 90 and, consequently, in braking down the ladder.

Fig. 12 shows the scale 5 pressed against a wall P. Since it is a view of principle, only the essential functional elements of the device according to the invention have been shown, know the pivot 35, the cradle 4, the attachment means 7 and the rigid connection 9. The scale 5 is secured on the pivot 35 via the cradle 4, and below by means of the rigid connection 9 fixed to the attachment means 7. The device according to the invention further improves the stability of the ladder by increasing the upper pressing force against the wall P. To do this, scale 5 is arched as the drawing illustrates it, by pulling on its base towards outside according to arrow F, then blocking in length of the arm 90 by means of the screw 91. If necessary, we can provide a ground support for two ladder uprights, using two crutches level adjustment, known per se.

Two people are enough to set up the scale which could even be carried out by a alone when needed. Total operation time which, as a reminder, is more than twenty minutes currently despite the help of four people, is reduced in a big way since it is around ninety seconds. On the other hand, for development lengths remaining within limits reasonable, the scale can be used without support higher, i.e. simply blocked in tilt by means of the rigid link 9.

Fig. 10 illustrates the case where the land adjoining the wall against which the ladder 5 must be supported is not horizontal, but inclined parallel to the wall. Vehicle 1 will then be oriented in the direction of the slope, which will advance the slide 70 on slide 80 to find the balance of the socket 35, condition on which the verticality depends transverse scale.

If the slope is very steep, the useful length of the slide 80 will not be sufficient. For this case, it an advanced position of the carriage 3 on rail 2 relative to position E, in which it can be immobilized, Fig. 11. The vehicle 1 will then have been oriented in the direction of rise, and the slide 70 will be moved back as it fits on slide 80. Note that in the direction normal to the wall, the slope does not of importance.

In addition to its great practical interest, the device according to the invention has the advantage of grouping little elements easy to install on a vehicle van type utility vehicle. It should also be noted that the sliding ladder mounted in the device remains perfectly usable independently of it, since it is immediately separable from cradle.

Claims (10)

1. A device for manoeuvring an extension ladder (5) which, mounted on a vehicle (1), is characterised in that it has :

   a cantilevered pivot (35) supported on the vehicle (1) so that it can be disengaged relative to the body of the vehicle;

   a securing means (7) mounted on the vehicle (1) at a distance from and underneath the pivot (35) to provide a fixing point substantially in vertical alignment with the latter;

   a cradle (4) in which the ladder (5) is secured by means of its basal plane section(50) so that the other planar sections (51, 52) of the ladder can be freely manoeuvred relative to said basal plane section (50), said cradle (4) being in an intermediate position between the ends of the basal plane section (50) and having a means (6) so that it can be received and secured on said pivot (35) to form a cardan coupling; and

      a means of adjustable length (9) to form a bottom rigid link, the length of which can be adjusted between the lower part of the basal plane section (50) of the ladder and said securing means (7) underneath the pivot (35), said rigid link (9) being designed to hold and keep the ladder (5) stable both in its transverse plane and its plane of inclination.
2. A device as claimed in claim 1, characterised in that the means (9) has a swivel-mounted bracket (93, 94) on either side of the basal plane section (50) of the ladder (5) as well as a telescopic median arm (90) provided with a progressive locking means or brake (91) to adjust the length thereof.
3. A device as claimed in claim 1 or 2, characterised in that the pivot (35) is a bushing of circular cross-section having a vertical axis, designed to receive a bottom stem of means (6), the top of which is mounted with a bearing (62) in which a transverse shaft (44) of the cradle (4) is mounted so that it can rotate freely, the shaft (44) also being able to oscillate in the bearing (62).
4. A device as claimed in claims 1 to 3, characterised in that the pivot (35) is mounted at the rear end of a longitudinal rail (2) secured onto the roof of the vehicle (1) and overhanging at the rear.
5. A device as claimed in claim 4, characterised in that the pivot (35) is supported on the rail (2) by means of a carriage (3) so that it can be displaced as a unit with the ladder (1) and its cradle (4) between a rear service position (E) and a front transporting position (L).
6. A device as claimed in claim 5, characterised in that it has a means which allows the carriage (3) to be immobilised in a service position which is farther forward than position (E).
7. A device as claimed in claim 5 or 6, characterised in that in the front position (L), it has a support formed by posts (100) and rollers (101) on which the ladder is received and secured in front of the cradle (4) when in the transporting position.
8. A device as claimed in one of claims 4 to 7, characterised in that the securing means (7) is mounted on an arm (8) attached to the rear of the vehicle underneath the rail (2) parallel therewith and in the same vertical plane, the securing means having a slide block (70) mounted on a slide (80) located on the top of the arm (8), said slide block bearing a fixing element and being provided with a brake (71) to allow it to be locked at any point whatsoever on the slide (80).
9. A device as claimed in claim 8, characterised in that said fixing element mounted on the slide block (70) is a vertical, cylindrical stem (72) on which a ring (6) provided at the free end of the rigid linking element (9) locates.
10. A device as claimed in one of claims 1 to 9, characterised in that the links between the basal plane section (50) of the ladder (5) on the one hand and, on the other, the various elements to which it is secured - cradle (4), bottom rigid linking means (9) - are provided in the form of transverse rods (43, 95) which are inserted through the bars of the basal plane section (50).

Images