Abstract:
A bellows has integral connecting members joining the side wall and floor or roof fabricated from a sheet of flexible material with displaced longitudinal folds having adjacent seams to form a tongue and a pocket for receiving the tongue when the sections are pivoted with respect to one another.

Description:
BACKGROUND OF THE INVENTION 
     A preferred use of correspondingly dimensioned bellows is the protection of the passage area between two vehicles coupled with one another in an articulated manner. If two rail-borne or road vehicles coupled with one another in an articulated manner are used for passenger traffic, a passage device, which permits persons to pass over from one vehicle to the other, is commonly provided between the vehicles. To make possible such passage from one vehicle to the other without exposure to adverse environmental effects, such a passage device is surrounded with a passage protection device, and this passage protection device is frequently a bellows, in which a plurality of folded webs of fabric following one another in the longitudinal direction of the vehicles form, due to being connected to one another along the longitudinal edges, a tube which is closed all around and is connected to the front wall of one of the two vehicles at one end, and to the rear wall of the other of the two vehicles at the other end. 
     Such bellows have been generally known and frequently used; they are proven passage protection devices, which guarantee reliable protection for persons passing over between the vehicles for a long time; but they hardly hinder the relative movements between the vehicles, which are necessary for the travel of the vehicle. 
     In such a bellows, the roof, the side walls and the floor are assembly units manufactured separately, which are fitted together at the mutually corresponding edges to form the tube with a rectangular cross section. Particular attention must be paid to the transition areas between the side walls and the roof as well as between the side walls and the floor from the viewpoint that they shall define the contour of the bellows, on the one hand, but, on the other hand, they should not lead to any undesired stiffening of the bellows, nor hinder the mobility of the vehicles in relation to one another. In addition to this viewpoint, there arises the problem of special risks, be it due to rotting or to the risk of damage by external effects. If the side walls and the floor are fitted together, the connection device is particularly at risk. 
     SUMMARY OF THE INVENTION 
     The present invention is based on a bellows in which each web of fabric extends in one piece over the respective transition area between a side wall of the bellows and the floor of the bellows, and its task is to characterize a bellows in which the transition area in each web of the bellows is prepared by a special folding technique such that it optimally satisfies the requirements imposed. 
     The features of such a bellows become apparent from the claims, which are explained below with reference to the drawing bellows. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     In the drawings, 
     FIGS. 1-3 show three consecutive sections during the preparation of a fold, which passes over the transition area between a side wall and the floor of the bellows, and which can be seen as a plurality of folds as they follow one another in the longitudinal direction of the tube formed by the bellows, 
     FIGS. 4-6 show movement processes taking place in the area of a transition area formed by folding between the floor of the bellows and a side wall of the bellows, 
     FIG. 7 shows a fold cross section for additional explanation of the present invention, and 
     FIG. 8 shows a fabric corner cut. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The preparation of a bellows according to the present invention begins, for each fold, with an initially flat material web 1, which is folded in the shape of a peaked roof, so that two outer material web longitudinal edges 2, 3 and one ridge edge 4 are formed, wherein the two fold panels 5, 6 extend from the ridge edge 4 to one of the fold longitudinal edges 2 and 3, respectively, forming a fold angle 7. A seam is prepared in the area of the ridge edge 4, and the seam consists of two sections 8 and 9, whose end points facing each other are located at a predetermined distance from one another and are designated by A and B. The seam section 8 adjoining point A will be located in the floor area of the finished bellows, and the seam section 9 adjoining point B will be located in the area of a side wall of the finished bellows. The preparation of a seam is the preferred method in practice, but this shall not exclude other manners of fastening; bonding and stitching are examples of equivalent techniques. 
     The next step in the preparation of a bellows according to the present invention, explained on the basis of a single fold, is shown in FIG. 2 as the pivoting of the material web section adjoining point B with the seam section 9 in the direction of arrow 10, wherein the fabric web section designated by point B protrudes, in the manner of a tongue, into a pocket-shaped section of the material web section designated by point A (arrow 11), and an overlapping with a radius is formed. 
     A respective clamping frame 12 and 13, which is at the same time used to connect the nearest material web, not shown, to the material web shown, is now placed on each of the outer material web longitudinal edges 2, 3. 
     The seam section 8 is relatively short, and the section of the material web, which now forms a section of the floor of the bellows, has the shape of a peaked roof in this area only, and the adjoining part of the material web assumes, according to FIG. 3, the shape of a groove, which has an approximately semicircular cross section, is open to the outside, and is grasped by a respective frame 12 and 13 at the two longitudinal edges. 
     In contrast, the seam section 9 is as long as the material web section adjoining point B, so that the material web section adjoining point B has a groove with a triangular cross section, which is open to the outside, between the frames 12, 13 over its entire length. 
     As can be seen, the floor of the bellows passes over on the inside into the side wall of the bellows, while this transition is arch-shaped on the outside. 
     The design of the bellows is consequently characterized in that the seams and overlaps are placed during the folding such that the transitions between the folds and overlaps roll relative to one another when the folds are pulled apart or pushed together during rotary movement around the vertical axis (FIGS. 1 through 3 for the movement process during the manufacture). The distances between the fold seams and overlaps are selected to be such that the extension of the side fold and that of the floor fold are identical. This means maximum extension. 
     The movement process in the bellows during corresponding movements of the vehicle are now explained on the basis of FIGS. 4-6, again based on the example of a fold of the bellows consisting of a plurality of such folds. 
     During straight-line travel of the articulated vehicle, which is preferably an articulated bus for road traffic, i.e., trackless travel, even though this is not a prerequisite according to the present invention, the folds have the shape according to FIG. 4, which is the shape shown in FIG. 3. 
     When the vehicle is traveling in a curve, the situation according to FIG. 5 arises for the transition area inside the curve between the floor and the side wall that is on the inside of the curve. Point A is moving upward (arrow 14), and point B is correspondingly moving downward (arrow 15); in addition, it is moving into the pocket formed in the floor of the bellows, and the overlap is &#34;rolling in.&#34; The two frames 12, 13 approach each other in the same manner (double arrows 16). 
     At the same time, the situation according to FIG. 6 arises for the transition area on the outside of the curve between the floor and the side wall located on the outside of the curve. Point A is moving downward (arrow 17), while point B is moving upward and outward (arrows 18, 18&#39;). The overlap is &#34;rolling up.&#34; The two frames 12, 13 are moving away from one another (double arrows 19). 
     The folding of the corner areas is designed such that the fabric, i.e., the material web, can be used completely, i.e., up to 100%, for the extension in the side (free fabric), as is shown in FIG. 7. 
     The radius 20 in the area of the transition of the frames 12, 13 between the floor area 21 of the bellows and the wall area 22 of the bellows is facilitated by the design of the corner cut according to FIG. 8. The fabric or material web has symmetrical, groove-like incisions 23, 24 from the side edges 2, 3 in the area between the points A and B. 
     As was mentioned above, a plurality of material webs are fitted together, as was shown and described, in the frame 12, 13 to form a tube of rectangular cross section, and the end frames at the two ends of the bellows are designed to be such that each of the two ends can be attached to one of the two vehicles connected to one another in an articulated manner.