Like escalators, travelators are conveying devices used to move people and goods. They differ from escalators e. g. in that they often work in a substantially horizontal position or in a position slightly inclined relative to their direc- tion of motion, so that successive steps, i. e. pallets, form a substantially even and rectilinear transport track instead of stair-like steps as in escalators. Travelators are also referred to as moving sidewalks and autowalks.

In prior-art travelators, autoramps and escalators, the pal- lets or steps are typically connected to an endless chain, belt or equivalent serving as a drive element by means of a separate coupling element. In prior-art solutions, the cou- pling arrangements are complicated and often also require the use of special tools for the coupling to be successfully performed in the desired manner. Long travelators contain a large number of pallets, each one of which has to be coupled to the drive element either by one end or by both ends.

These prior-art coupling solutions and the associated ad- justments are slow and complicated to implement, which is why the installation times are very long especially when long travelators are to be installed. This is expensive and even otherwise undesirable. In addition, maintenance and repair operations take a longer time because the release and re-mounting of prior-art coupling solutions is a slow proc- ess. Another problem are coupling elements of a larger size, which take up space around their path of motion and add to the weight of the structures. An additional problem in prior-art coupling solutions is the very chain serving as a drive element, which has to be of a special construction due to the coupling. Such a chain, which is specific only to a

given application, is generally expensive and may be diffi- cult to obtain in urgent cases of repair.

The object of the present invention is to overcome the above-mentioned drawbacks and to achieve an arrangement for coupling the pallets of a travelator, moving ramp or escala- tor or an equivalent apparatus, an arrangement that is of economical cost and allows easy coupling and wherein the pallet is coupled especially to a chain functioning as a drive element moving the pallets. The pallet coupling ar- rangement of the invention is characterized by what is dis- closed in the characterization part of claim 1. Other em- bodiments of the invention are characterized by what is dis- closed in the other claims.

Inventive embodiments are also presented in the description part and drawings of the present application. The inventive content disclosed in the application can also be defined in other ways than is done in the claims below. The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of explicit or implicit sub-tasks or in respect of advantages or sets of advantages achieved. In this case, some of the attributes contained in the claims below may be superfluous from the point of view of separate inventive concepts.

Within the framework of the basic concept of the invention, features of different embodiments of the invention can be applied in conjunction with other embodiments.

The advantages provided by the pallet coupling arrangement of the invention include easy and fast installation, which means that the installation, maintenance and repair times are short and consequently the downtimes are also short. In addition, the coupling solution is simple and reliable, so the coupling is safe and requires no special tools in order to be successfully carried out. A further advantage is that the drive elements used may consist of standard chains,

which are economical and quickly available when needed. Yet another advantage is that the coupling element is of small size and light weight, so the coupling solution does not take up much space around its path and the coupling pieces do not strain the travelator structures by their weight. A significant advantage is that the pallet can be connected to the chain from above. Thus, the pallet can be easily fas- tened to the chain during installation, and during mainte- nance or repair the pallet can be easily released from the chain and secured to it again. In the most preferred embodi- ments of the invention, the pallet can be lowered to its position relative to the chain and the pallet track and con- nected to the chain without lateral movement of the chain or the pallet lowered into position. As the connection is easy to make and release, installation and maintenance work re- quires less time.

In the following, the invention will be described in detail with reference to an embodiment example and the attached drawings, wherein Fig. 1 presents an oblique top view of a typical pallet in which the coupling arrangement of the inven- tion can be used, Fig. 2 presents a more detailed view of the pallet of Fig. 1 as seen from the end of the pallet, Fig. 3 presents an oblique top view of the main compo- nents of the pallet coupling arrangement of the invention, Fig. 4 presents a detail of the pallet coupling ar- rangement of the invention in oblique top view, Fig. 5 presents an oblique top view of the main compo- nents of the pallet coupling arrangement of the invention in an assembled state, and Fig. 6 presents a top view of a pallet provided with a pallet coupling arrangement according to the in- vention.

The pallet structure 1 of the invention comprises a pallet body 3, which has preferably been produced by extruding a suitable profile from aluminum or some other appropriate metal or metal alloy. During manufacture of the profile, a given profile is extruded in bars of a length suited for manufacture, transport or other purposes. Later during manu- facture of the pallet, parts of a length exactly suited for the purpose are cut from these profiled bars. Thus, the same profile can easily be used for pallets of different lengths, which makes it easy to vary the width of the conveyor track of the travelator. Secured to the pallet body 3 are wheels 4 at each end of the pallet and likewise at least at one end a fastening element 20, by means of which the pallet 1 is cou- pled to an endless chain, toothed belt, rope or equivalent actuating element serving to move the pallets. The fastening element 20 is secured e. g. to a mounting hole 5 provided at the end of the body 3. The holes and other shapes provided in the body 3 for mounting the fastening elements and wheels may be profile shapes or separately made in the profile.

A surface part extruded from plastic or equivalent material is fastened onto the body 3 of the pallet 1 e. g. by snap-on couplings or corresponding shape-locked couplings. The sur- face part preferably consists of one or more surface plates 2a-2c of suitable width, which are also provided with the necessary corrugations in the direction of the pallet track.

Each surface plate 2a-2c is provided with snap-on coupling elements or corresponding coupling elements 6, preferably in the lower part or on the lower surface of the surface plates, placed at suitable points e. g. at the ends and in the middle part of the surface plates, in such manner that the surface plates are firmly held in position on the pallet body 3 and that the surface plates can be easily pressed into position and that they can also be easily released from the body using a tool suited to the purpose. Correspond- ingly, placed at suitable points in the upper part of the

pallet body 3 are counterparts 7 corresponding to the afore- said coupling elements, so that the coupling elements 6 can be fastened to them in a shape-locked manner.

The width of the surface plates 2a-2c has been so defined that, using a suitable number of surface plates of the same width, it is possible to cover pallet bodies of different lengths, so the same parts can be used to assemble pallets of different lengths.

Fig. 1 and 2 present a pallet 1 provided with differently colored surface plates 2a and 2b and also transparent or translucent surface plates 2c, under which transparent or translucent surface plates 2c it is possible to place be- tween the body 3 and the surface plate 2c a notice, adver- tisement or other element varying the appearance, printed on paper, plastic or equivalent material. By illuminating such an element from below or from the side, various visual ef- fects can be produced. The transparent or translucent sur- face plates 2c are preferably placed in the middle part of the pallet 1. By disposing surface plates of different col- ors in different places in the longitudinal direction of the pallet 1, it is possible to vary the appearance of succes- sive pallets, so it will be easy to change the appearance of the conveyor track of the travelator.

The body 3 of the pallet 1 consists of one or more profiled parts placed side by side. The body 3 is preferably composed of two body halves consisting of identical, mutually upside- down oriented profiled parts, which are also horizontally conversely arranged. Thus, the two halves of the body can be easily cut off the same profiled bar and turned into mutu- ally opposite positions and joined together during assembly of the body.

Figures 3-5 present a fastening element 20 used in the coupling arrangement of the invention, designed to connect

the pallet to the chain 12 that moves the pallets. The fas- tening element 20 comprises at least a coupling piece 8, a cylindrical shaft 9 fixedly secured to the coupling piece 8 and a locking element 13, such as a spring. Provided in the lower surface of the coupling piece 8 are two downwards- opening slots 10, the distance between which corresponds to the distance between holes in the chain 12. The slots 10 extend in the same direction with the shaft 9 and at the same time transversely, i. e. perpendicularly to the direc- tion of motion of the pallets 1. The width, height and ra- dius of curvature at the upper edge of the slots 10 are suitably so designed that two fastening pins 11 of a diame- ter corresponding to that of a normal chain pin can be in- serted into the slots 10, yet without making the slot-and- pin coupling too loose. Since there are chains of many widths, the fastening pins 11 used may be normal longer chain pins of a wider chain instead of separate fastening pins. In this case, the longer chain pins function as fas- tening pins 11. Hereinafter, fastening pins'11 refers to both longer chain pins and fastening pins specially made for this purpose.

The spring used as a locking element 13 is of a size and shape such that it can be locked onto the coupling piece 8 by spring force. The locking element 13 is a roughly U- shaped piece made from thin sheet metal, and it has in its bottom part two protrusions 14 whose size, orientation and mutual distance correspond to the size, orientation and mu- tual distance of the slots 10. Moreover, the locking element 13 has at each upper edge an inward elbow 21, which is fit- ted to meet the upper surface of the coupling piece 8 when the pallet is coupled to the chain.

Fig. 4 presents a more detailed view of the counter- structure in the body part of the pallet 1 for coupling the fastening element 20 to the pallet 1. The body 3 may be pro- vided with a separate coupling piece 15 as shown in the fig-

ure, with a mounting hole 16 for the shaft 9 of the fasten- ing element, or the body may be provided with a mounting hole 5 corresponding to hole 16 as mentioned above. In this case, no coupling piece 15 is needed. From the point of view of the invention, either solution will serve the same pur- pose. The mounting hole 5,16, which is located at the end of the pallet in the area between the wheels 4, is provided with bushes 17 functioning as slide bearings so that, when mounted in the mounting hole 5, 16 through the bushes 17, the outer end of the shaft 9 extends over the innermost bush 17. This protruding outer end of the shaft is provided with a groove 22 whereby the shaft is locked in position in the axial direction by means of a circlip 18. A further feature characteristic of the shaft 9 is that the shaft 9 extends in the same direction with the fastening pins 11 and substan- tially in the same plane with the axes of the fastening pins, preferably at an equal distance from the axes of the fastening pins.

If the shaft 9 is locked directly to the mounting hole 5 going through the entire pallet, then the lower surface of the pallet body has to be provided with recesses 19 as shown in Fig. 6 to allow the outermost bush 17 and the circlip 18 to be mounted in place. On the other hand, if a separate coupling piece 15 is used, then the pallet body has to be provided with a suitable space for this purpose.

Fig. 5 presents the pallet coupling arrangement in an assem- bled state. The coupling piece 15 may represent a separate piece or also a part of the pallet body. At the coupling point, instead of normal chain pins, the chain 12 is pro- vided with longer fastening pins 11, the other ends of which are inserted into the slots 10 in the lower surface of the coupling piece 8 so that the front surface of the coupling piece 8 is as close to the chain 12 as possible or in con- tact with the chain. With the fastening pins 11 in the slots 10, the locking element 13 is set from below onto the cou-

pling piece 8 so that the protrusions 14 in the bottom of the locking element 13 press the fastening pins 11 against the upper surface of the slots 10 and that the elbow 21 ex- tending inwards at each upper edge of the locking element 13 meets the upper surface of the coupling piece 8, pressing the locking element 13 tightly into position.

It is obvious to the person skilled in the art that the in- vention is not limited to the example described above, but that it may be varied within the scope of the claims pre- sented below. Thus, the structure of the fastening element 20 may differ from that described above, so for example the coupling piece 8 and the locking element 13 may be of some other type than in the above description. The fastening ele- ment 20 may be e. g. so constructed that the shaft 9 is not a fixed part of the coupling piece 8, but instead the coupling piece 8 is provided with a hole which is used to fasten the coupling piece onto a locking shaft locking the two halves of the body 3 together. The end of the locking shaft extends far enough out of the central hole of the body 3 to allow the coupling piece to be locked onto the locking shaft e. g. by means of a circlip.

The locking element corresponding to locking element 13 may also be a structure like that presented in Fig. 7 and 8. In Fig. 7, the locking element is a plate 23 which is provided with a central hole substantially corresponding to the cross-sectional shape of the coupling piece 8 and which is ready placed on the shaft 9 at the mounting stage. After the fastening pins 11 have been mounted into the slots 10 from below, the fastening pins can be locked in place by pulling the plate 23 onto the coupling piece, thus preventing them from falling out of the slots. The plate can additionally have at the lower edge of its central hole small upwards acting spring-like parts pressing the fastening pins 11 to the slots 10. Such a structure provides the advantage of easy locking and release. In addition, e. g. in connection

with maintenance, the plate will not be easily lost as it can be left on the shaft for the time of maintenance.

In Fig. 8, the locking element is a spring 24 corresponding to locking element 13. It has a construction that allows it to be pressed into position from above the coupling piece 8 in the direction of the arrow 25 to lock the fastening pins in the slots 10. In Fig. 8, the spring 24 depicted with a broken line represents the position of the spring before the spring 24 is locked in position on the coupling piece. The size of the spring 24 is so designed in relation to the cou- pling piece 8 that, when mounted in the locking position, the free ends of the spring will press the fastening pins into the slots 10 while the spring is simultaneously pressed against the upper surface of the coupling piece 8. The ad- vantage of this solution is that it permits very easy and quick installation. A correctly designed spring 24 is easy to press onto the coupling piece 8. Likewise, the spring can be easily removed by means of a suitable tool.

Similarly, it is obvious that, instead of the use of locking elements 13,23, 24, the slots 10 may be holes and the ends of the fastening pins 11 projecting from the chain can be locked on the back surface of the coupling piece 8 by means of circlips. In this case, the lower surface of the back part of the coupling piece may be provided with recesses or equivalent to allow the circlips to be mounted from the be- low. The recesses allow the surface of the locking piece to be evenly set against the pallet body. Instead of circlips, the fastening pins 11 may have bolt-like head with a diame- ter larger than the shank part of the pin. In this case, the fastening pins can be inserted into the holes of the cou- pling piece 8 from the side of the pallet, whereupon the chainl2 is fastened by its holes to the fastening pins. The holes of the coupling piece are in this case provided with countersinks on the back surface for the heads of the fas- tening pins.

It is additionally possible that the coupling piece 8 has only one slot 10 or hole, in which is mounted only one fas- tening pin 11 or equivalent of a design like a longer chain pin. This may be possible e. g. in light structures or if the chain 12 has thick pins in any case.

Instead of a fastening pin/fastening pins 11, the chain may also have another type of fastening part, e. g. a chain link shaped to permit fastening or some other detent for engaging the coupling piece 8. In the case of another type of fasten- ing part, the coupling piece is correspondingly specifically designed as required by such a detent. For example, a tooth- like peg provided with a hole and jutting out laterally from the side plate of a chain link could be coupled in the fas- tening element by means of a bolt or a suitable cotter pin arrangement.

It is likewise obvious that the shafts 9 may also function as locking shafts that lock the body structure composed of two separate profiled pieces together as a single assembly.

It is further obvious that, instead of a chain as described above, it is possible to use different types of chain struc- tures or equivalent as a drive element.

It is further obvious to the person skilled in the art that the coupling piece 8 may be rigidly fastened relative to the link of the chain 12, or that the fastening to the pallet is implemented between the joints/pins of the chain 12 at the link whereby the fastening to the chain 12 takes place.