The present invention generally relates to an ar¬ rangement in a foldable fire escape ladder and especially to a spacer member which is integrated with the ladder and which in the unfolded state of the ladder maintains it at a certain distance from e.g. the wall of a house for safer descent and rescue of persons in distress.

Several different types of fire escape ladders with or without spacer means are previously known, e.g. from DK-C-5297, DE-C-156,782, GB-A-1,421, 131, DE-OS-25,48, 867 and SE-B-415,051.

The fire escape ladder shown in DE-C-156,782 consists of tubular steps with stationary wall spacer members at- tached thereto and extending at right angles to the longi¬ tudinal direction of the ladder in the unfolded state thereof. One spacer member is arranged at each step and consists of a bent, U-shaped tube fixed to the respective ends of the step. One of the drawbacks of a ladder of this type having such spacer members is that it becomes very bulky when in the folded state. Another drawback is that the wall spacer members cannot be arranged at optional steps.

The same drawbacks are met with in the fire escape ladder shown in SE-B-415,051.

GB-A-1,421,131 shows a fire escape ladder having mov¬ able spacer members. These are designed as individual struts which are fixed to rigid elements connecting the steps to each other, and which can occupy two positions, viz. a first, folded-in position in which they are aligned with the rigid elements, and a second, folded-out position at right angles to the first position. The struts are in¬ tended to be moved from the first to the second position by the force ^• of gravity acting on the struts in the un- folded state of the ladder. One of the drawbacks of such a ladder construction is that the struts, because of oxida¬ tion, soiling etc. , in many cases are not folded out,

which may result in that the ladder will dangle, thus mak¬ ing the descent more difficult and jeopardising the safety of those in distress, to whom the fire escape ladder may be the only means of rescue. The fire escape ladder which has hitherto proved most useful is that shown in DE-OS-25,48,867. However, this ladder has no spacer members integrated therewith. As auxiliary equipment is available a tubular spacer member (see Fig. 1) provided with grooves and intended to be fixed between the ropes of the ladder at the upper end thereof. This is of course a substantial drawback since there is an obvious risk that either the spacer member is not acquired (for economic reasons) or, for some reason or other, it is not readily available in an emergency situa- tion. Another shortcoming inherent in this fire escape ladder is the way of folding it, which is done by turning the steps of the ladder alternatingly to the right and to the left, such that the ropes between the steps will rest in these. Such "crossing" of the ropes has however too often caused difficulties when using the ladder since it has not unfolded properly or, when unfolding, has caught in parts protruding e.g. from the wall of a house.

Fire escape ladders must however provide an infallib¬ ly reliable operation in all conceivable situations. Thus, it is of vital importance that all preparatory steps re¬ quired be taken before using the fire escape ladder. Part of such preparations is of course incumbent upon the buyer of the ladder, who must, for instance, find a suitable place for mounting the ladder, see to it that the ladder is solidly anchored, mark the evacuation way and practise the descent with all persons who may have to use this way of rescue in an emergency situation. It should be borne in mind that an emergency situation in which the fire escape ladder is the sole, relatively safe means of rescue, arises suddenly, often in the night, when most of the people involved are dazed by what has happened, that the electric power system is in most cases cut out, which

means that it is dark and difficult to find the way, and also that toxic, suffocating smoke hampers breathing and deteriorates visibility. The probability that anyone when in such a situation should start looking for and find a spacer member pertaining to the fire escape ladder and thereafter manage to mount it is very small. In many cases, the fire escape ladder will instead be used without the wall spacer member. Modern buildings, such as residen¬ tial buildings, office buildings, hotels etc., often have relatively smooth walls and so, a fire escape ladder thrown out of a window will bear directly on the wall of the building. For a width of the treads of the steps of but a few centimetres, the descent will become most dan¬ gerous since the risk of slipping off a step is obvious. Thus, a fire escape ladder needed in different emer¬ gency situations should be usable immediately, it should unfold with infallible certainty, and it should be main¬ tained at such a distance from the wall of a house that the steps will provide a safe foothold to those using the ladder, thereby ensuring a reliable descent.

One object of the present invention therefore is to provide a spacer member for a fire escape ladder that, meets the requirements stated above.

Another object of the present invention is to design the entire fire escape ladder in a manner to guarantee its intended function, thus making the descent completely re¬ liable.

The fire escape ladder with the spacer members should be of compact design so that it can easily be mounted above e.g. a window and/or be brought along when tra¬ velling, to be used in those cases where no other means of rescue is available.

Moreover, the fire escape ladder should be easy and economical to manufacture. According to the invention, these and other objects are achieved by means of an arrangement in a foldable fire escape ladder comprising individual, elongate spaced-apart

steps connected to each other, each step having a tread and at least one side wall, the arrangement being charac¬ terised by a groove integrated with each of said steps in the longitudinal direction thereof, an articulated spacer member mounted in the groove of one of said steps, and guide means for positively guiding the spacer member from a first, folded-in position in which it engages the ladder in the folded state thereof, to a second, folded-out position in which, in the unfolded state of the ladder, it extends at approximately right angles to the direction of unfolding of the ladder and to an engagement surface therefor.

Other advantageous embodiments and improvements are achieved by the features stated in the subclaims. Thus, the fire escape ladder may be provided with an active

(emergency lighting) or a passive (reflector) signalling means and/or acoustic alarm means (fire/smoke alarm).

Further, the fire escape ladder may be provided with means which in an indicated emergency situation discharges a plurality of steps from a mounting box for the ladder, which is provided e.g. above a window, so as to make it easier for a person in distress, who ought to be crawling on the floor where the smoke from the fire is not as con¬ centrated, to find his way to the fire escape ladder. Embodiments according to the invention of arrange¬ ments in a foldable fire escape ladder are shown in the accompanying drawings and will be described in more detail hereinbelow.

Fig. 1 is a perspective view of a prior art spacer member.

Fig. 2 is a perspective view of a spacer member, in¬ tegrated with a step included in a fire escape ladder, ac- cording to a first embodiment of the present invention, where the spacer member is in a first, folded-out posi- t on.

Fig. 3 is a perspective view similar to Fig. 2, but with the spacer member in a folded-down resting position. Fig. 4 is a perspective view of a spacer member, in¬ tegrated with a step included in a fire escape ladder, ac- cording to a second embodiment of the present invention, where the spacer member is in a first, folded-out posi¬ tion.

Fig. 5 is a perspective view similar to Fig. 4, but with the spacer member in a second, folded-down position. Fig. 6 is,a perspective view of the foldable fire escape ladder with integrated spacer members according to the invention in the folded state.

Fig. 7 is a perspective view, given by way of exam¬ ple, of a step provided with fixing grooves and corre- sponding to the step in Figs. 4 and 5.

Fig. 8 is a perspective view of a magazine adapted to receive the fire escape ladder and having beads mating with the fixing grooves.

Figs. 2 and 3 illustrate a first embodiment of an ar- rangement according to the invention used in steps 2 in¬ cluded in a fire escape ladder. Each of these elongate steps has a tread 4 which may be provided with friction- increasing means, such as grooves 6, raised portions and/or a friction-increasing coating, and two side walls 8, 9, of which only one wall 8 is necessary for achieving the technical effect of the invention. The outer face of the wall 8 has a bead-like projection 10. The projection 10 is preferably provided at the end of the side wall 8 facing away from the tread 4 so that the steps 2 can be stacked on each other, and forms an integral unit with the step 2. The projection 10 is provided with a groove 12 whose height preferably decreases from the end of the groove which is remote from the opening thereof, towards the groove opening to prevent a spacer member 15 inserted in the groove 12 from sliding out of the groove trans¬ versely of the longitudinal direction of the step 2. Natu¬ rally, the spacer member can be secured to the step in any

other suitable manner. The spacer member is articulated throughout its entire length and thus divided into a part 14 fixedly connected to the step 2, and a pivotable part 16. The pivotable part 16 preferably has a horizontal working position in the unfolded state of the ladder and is pivotable upwards or downwards to a resting position in the folded state of the ladder (see Fig. 6), i.e. pivot¬ able through about +/- 90° about the horizontal folded-out working position. The spacer member is preferably connect- ed to the step along the entire length thereof. The sur¬ face of engagement of the spacer member with e.g. the wall of a house in the unfolded state of the ladder can be in¬ creased by means of an angled element 18 provided at the side of the spacer member remote from the groove. A guide means, which in this embodiment consists of ropes 20 and 22, is provided for guiding the spacer member to its two positions, i.e. the working position or the resting position. The rope 20 is fixed to the pivotable part 16 of the spacer member and to a step immediately above the step in which the spacer member is mounted, and the rope 22 is fixed to the pivotable part 16 of the spacer member and to a step immediately below the step in which the spacer member is mounted. The ropes 20, 22 have such a length that they are stretched when the wall spacer member is in its working position in the unfolded state of the fire escape ladder.

Figs. 4 and 5 illustrate a second, preferred embo¬ diment of the inventive arrangement used in steps 32 included in a fire escape ladder. Each of these elongate steps has a tread 34 which may be provided with friction- increasing means, such as grooves 36, raised portions and/or a friction-increasing coating, and two side walls 38, 39, of which only one wall 38 is necessary for achiev ing the technical effect of the invention. In this embodi ment of the present invention, an approximately semicir¬ cular groove 40 (see Fig. 5) is provided in the side wall 38. The groove in the side wall 38 of the step suitably

extends throughout the entire length thereof so as to for an elongate, semicircular channel which is open at its ends. The groove 40 has an open end 42 and a closed end 44. Thus, an elongate opening is defined in the side wall 38. This opening is preferably located immediately below the tread 34 for reasons which will be stated in more de¬ tail hereinbelow.

A spacer member 46 intended for a step having such a groove 40 consists of a plate having a length which suit- ably corresponds to the length of the step 32 or at least of the groove 40, in case the groove is shorter than the step. One end 48 of the plate is so curved that it is re¬ ceived in the groove 40 substantially without any play when -the spacer member 46 is inserted in the groove of the step, and that the terminal edge 50 (see Fig. 5) of the plate located at the end 48 thereof comes into engagement with the closed end 44 of the groove when the spacer member 46 is in a folded-out position in the unfolded state of the ladder, the other, flat end 52 of the plate being substantially horizontal. The end 52, whose top face may be provided with friction-increasing means, such as grooves, raised portions and/or a friction-increasing coating 54, is located, because of an increased thickness which via an abutment 55 (see Fig. 5) passes into the curved end 48, on substantially the same vertical level as the tread 34 of the step, this making the descent consi¬ derably safer. In this embodiment, the spacer member 46 thus is pivotable downwards to a resting position in the folded state of the ladder, but it is of course also con- ceivable to provide a spacer member which is pivotable upwards to its resting position and by gravity is folded out to its working position in the unfolded state of the ladder. The groove 40 and the curved end 48 of the spacer member are so designed that the spacer member 46 remains in engagement with the groove 40 also in the resting position of the spacer member. The surface of engagement of the spacer member with e.g. the wall of a house in the

unfolded state of the ladder can be increased also in this embodiment of the present invention, by means of an angled edge element (not shown) provided at the terminal edge 56 of the spacer member remote from the groove 40. A guide means, which in this embodiment consists of a spring (not visible), is used for guiding the spacer member from its resting position to its working position in which the terminal edge 50 comes into engagement with the closed end 44 of the groove, which end thus serves as an abutment. The spring is so mounted between the side wall 38 imme¬ diately below the opening of the groove 40, and the flat underside of the spacer member that the spacer member, by the force of the spring, is moved to its folded-out posi¬ tion when the ladder is in its unfolded state. Also in this embodiment, the spacer member may of course be brought to its folded-out position by a rope which suitably is fixed between the spacer member and a step immediately above the step 32 in which the spacer member is mounted. In this case, a single rope would be sufficient since the spacer member cannot be folded up above horizontal position.

Fig. 6 shows the fire escape ladder with the spacer members according to the present invention in the folded state. In the embodiment shown in Fig. 6, the folded ladder is provided with simple covers 60, 62 which may have several functions. The covers 60, 62 may serve as mounting or suspension means, in which case the covers suitably are connected to each other. The covers 60, 62 maintain the spring-loaded spacer members according to th second embodiment described above, in their respective resting positions and conceal the ropes which connect the steps to each other and which, as opposed to the arrange¬ ment of DE-OS-25,48,867 mentioned above, are placed in loops beside the steps stacked on each other, to permit a more rapid, complete unfolding of the fire escape ladder in an emergency situation.

Fig. 7 shows a step 72 corresponding to the step in Figs. 4 and 5 and included in a fire escape ladder and provided with the second, preferred arrangement according to the invention. The step 72 has a tread 74 which may be provided with friction-increasing means, such as grooves 76, raised portions and/or a friction-increasing coating, and two side walls 78, 79. Also in this case, an inventive spacer member, described above with reference to Figs. 4 and 5, is intended to be mounted in a corresponding groove 40 in the side ,wall 78. The side wall 79 has a substan¬ tially vertical part 80 which in this embodiment is pro¬ vided with recesses or fixing grooves 82, 84. These fixing grooves are intended to mate with corresponding beads 102, 104 (see Fig. 8) for fixing the position of the folded ladder and guiding the steps when unfolding the ladder. Fig. 8 shows a holder or a magazine 90 for storing the fire escape ladder in its folded state in a safe and easily accessible way. The magazine essentially consists of a bottom plate 92, side walls 94, 96 and a whole or, as in the illustrated example, divided top plate 98, 100. The bottom plate has beads 102, 104 which correspond to the fixing grooves 82, 84 (see Fig. 7) and fix the steps in the magazine so as to define a space between the ends of the steps and the side walls 94 and 96, respectively, for storing the ropes connecting the steps to each other, and which guide the steps when being removed from the magazine in order to bring the fire escape ladder to its unfolded state. The lower part of the magazine 90 is advantageously- provided with means (not shown) for locking the lowermost step of the ladder in order to prevent the ladder from being unintentionally unfolded.

The advantages of the present invention can be summed up as follows:

(1) The fire escape ladder with the spacer members according to the present invention unfolds more rapidly and more reliably than any prior art fire escape ladder.

(2) Thanks to the spacer members integrated with the steps, the ladder will be maintained when in its unfolded state at such a distance from e.g. the wall of a house that the descent becomes considerably safer as compared with prior art ladders.

(3) Especially the second embodiment of the step and the spacer member as described above provides a firm hold to the climber's feet since the spacer member is on approximately the same vertical level as the step in which it is mounted, while at the same time both the step and the spacer member are provided with friction-increasing means.

(4) The steps can be stacked on or in each other, and since the ropes connecting the steps to each other are placed beside the steps and the spacer member can be folded down to resting position, the ladder becomes very compact and easy to handle when in its folded state.

(5) If the steps are provided with fixing grooves, as exemplified in Fig. 7, the ladder can be folded up very easily, stored in a convenient manner and unfolded in a most reliable fashion.

(6) Since the steps and the spacer members can be ex¬ truded from aluminium, the ladder can be manufactured at a very reasonable cost, so that emergency exits equipped with a fire escape ladder can be arranged not only in pub¬ lic buildings, hotels, on ships etc., but also in smaller residential buildings, private houses etc.