STEP DEVICE FOR A RAIL VEHICLE

Abstract

A step device for a rail vehicle includes a step platform, a housing from which the step platform is extendable and retractable again, and a regulating unit for controlling the extension and retraction movement of the step platform. The step platform includes a plurality of step contact segments which, when subjected to pressure, generate signals which are transmitted to the regulating unit. The step contact segments are disposed at predefined distances greater than zero with respect to one another on the step platform in such a manner that an object of predefined minimum contact area with the step platform subjects at least two directly adjacent step contact segments to pressure, and the regulating unit is configured in such a manner that a relevant object is recognized only when signals of two directly adjacent step contact segments are transmitted.

Claims

1-10. (canceled)

11. A step device for a rail vehicle, the step device comprising: a step platform; a housing from which said step platform can be extended and retracted again; and a regulating unit for controlling an extension and retraction movement of said step platform; said step platform including a plurality of step contact segments generating signals transmitted to said regulating unit upon said step contact segments being subjected to pressure; said step contact segments being disposed on said step platform at predefined distances greater than zero relative to one another, causing an object having a predefined minimum contact area with said step platform to subject at least a directly adjacent two of said step contact segments to pressure; and said step platform configured to generate and transmit a signal representing a relevant object to said regulating unit only when the object on said step platform subjects said two directly adjacent step contact segments to pressure, or said regulating unit configured to detect a relevant object only upon signals being transmitted from said two directly adjacent said step contact segments.

12. The step device according to claim 11, wherein said step contact segments are strip-shaped and are disposed beside one another, parallel to a direction of said extension and retraction movement of said step platform.

13. The step device according to claim 11, wherein said step contact segments are configured with geometric shapes and are distributed over said step platform.

14. The step device according to claim 11, wherein said step contact segments are disposed at equal distances from one another.

15. The step device according to claim 11, which further comprises non-sensitive regions disposed between said step contact segments, said step contact segments being smaller than said non-sensitive regions.

16. The step device according to claim 11, wherein said step contact segments each have a width b predefined as a function of a distance u from a directly adjacent step contact segment, wherein b = u*c, and c < 0.5.

17. The step device according to claim 16, wherein said predefined distance u between two directly adjacent step contact segments is at most 20 mm.

18. The step device according to claim 11, wherein said step contact segments are configured to only generate signals transmitted to said regulating unit upon said step contact segments being subjected to a predefined minimum pressure.

19. The step device according to claim 11, wherein: said step contact segments are disposed at a distance from one another in a direction of said retraction and extension movement of said step platform and transversely to said direction of said retraction and extension movement of said step platform; an object having a predefined minimum contact area with said step platform applies pressure to a first one of said step contact segments, to at least a directly adjacent second one of said step contact segments disposed at a distance from said first step contact segment transversely relative to said direction of said retraction and extension movement of said step platform, and to at least a directly adjacent third one of said step contact segments disposed at a distance from said second step contact segment in said direction of said retraction and extension movement of said step platform; and said step platform is configured to generate and transmit a signal representing a relevant object to said regulating unit only when the object on said step platform applies pressure to said first step contact segment and to said second step contact segment and to said third step contact segment, or said regulating unit is configured to detect a relevant object only upon signals being transmitted from said first step contact segment and from said second step contact segment and from said third step contact segment.

20. A vehicle, comprising at least one step device according to claim 11.

Description

[0029] FIG. 1 shows a cross section through a step platform having a step contact mat from the prior art,

[0030] FIG. 2 shows a step device with small objects on its step platform,

[0031] FIG. 3 shows a cross section through the step device according to FIG. 2,

[0032] FIG. 4 shows, schematically, a step platform of a step device according to the invention,

[0033] FIG. 5 shows, schematically, the step platform from FIG. 4 with an object to be detected as relevant for the control of the retraction and extension movement,

[0034] FIG. 6 shows a further embodiment of a step platform according to the invention.

[0035] A conventional extendable step platform 1 having a step switching mat for the detection of weight is illustrated in FIG. 1. The mat has two homogenous and electrically conductive contact surfaces 5, 6 which lie above one another and which have electric contact with each other under a step loading, whereupon a signal is generated and is transmitted to a regulating unit for controlling the extension and retraction movement of the step platform 1. Because of the all-over design of the contact areas over the complete step area of the step platform 1, it is, however, not possible to distinguish between a step loading by a passenger and a step loading by foreign bodies, such as scatter grit 7 that is clamped in, as illustrated in FIG. 2 and FIG. 3. Clamping of the scatter grit 7 between the step platform 1 and its housing 2 as the step platform 1 is retracted leads to a detection of a step loading in the electronic regulating unit and thus also to the stopping of the extension or retraction movement originally envisaged for the protection of the passenger. The retraction direction is identified by an arrow.

[0036] FIG. 4 shows, schematically in a three-dimensional illustration, an extendable step platform according to the invention for a rail vehicle, which can be extended out of an associated housing and is equipped with a step contact mat divided up into a plurality of step contact segments 3 which, when subjected to pressure, generate signals which are input into a regulating unit. Here, the step contact mat also comprises two electrically conductive contact areas lying one above another. Here, the lower contact area 6 is formed over the entire area. The upper contact area 5, on the other hand, has an interrupted grid-shaped structure.

[0037] Non-sensitive regions 4 are arranged between strip-shaped step contact segments 3 that are arranged beside one another and are oriented parallel to an extension and retraction direction of the step platform 1 from and into the associated housing. If, then, smaller foreign bodies such as scatter grit are located on the non-sensitive regions, even when these are clamped in between the step platform and the associated housing as the step platform is retracted into the housing, no electrical contact is produced between the contact areas 5 and 6, and thus no signal is generated and transmitted to the regulating unit.

[0038] In order likewise not to generate and to transmit a signal or to be able to ignore this signal if the scatter grit is resting on one of the step contact segments 3, the distances between the step contact segments are dimensioned in such a way that an object with a predefined minimum contact area with the step platform 1 applies pressure to at least two directly adjacent step contact segments 3, and the step platform 1 is designed in such a way that a signal representing a relevant object is generated and transmitted to the regulating unit only when the object on the step platform 1 subjects two directly adjacent step contact segments 3 to pressure or the regulating unit is designed in such a way that a relevant object is detected only when signals are transmitted from two directly adjacent step contact segments 3.

[0039] The distance of two adjacent step contact segments 3 and therefore the width of the non-sensitive regions 4 between them is dimensioned in such a way that each object having a minimum contact area 8 relative to the step platform with a diameter of 40 mm always touches at least two directly adjacent step contact segments 3 and can apply pressure, as sketched in FIG. 5. Smaller objects, such as scatter grit 7, can thus remain unconsidered.

[0040] A further embodiment is sketched in FIG. 6. The step contact segments 3 are designed as flat geometric figures, here as small rectangles. In addition to the distance perpendicular to the retraction and extension movement of the step platform 1, each step contact segment 3 additionally is at a distance to its immediate neighbors in the direction of the retraction and extension movement of the step platform 1. It is also possible to speak of interrupted, strip-shaped step contact segments 3. A signal is generated or the signals from the step contact segments are detected as relevant by the regulating unit only when a first step contact segment 31 and its immediate neighbors 32 and 33 are subjected to pressure in the direction and transversely to the direction of the retraction and extension movement of the step platform 1.