Scrolling display
A roll tape display is a special design of a display board , based on the model of a roll film from a camera . It consists of a printed roll tape made of plastic , linen fabric or silk , also known as broseband , line film , target film or transparent in Switzerland , which is wound on two horizontal rolls or spools fixed in a housing at the top and bottom, or vertical rolls fixed to the left and right . The section of the conveyor belt that is stretched between the two rollers is visible to the outside. A purpose of use of conveyor belts is, for example, the display of the line name , the destination or the route on or in local public transport .
description
The distance between the rollers determines the maximum size of a scrolling display field. There is a window on the front of the box so that the display can be viewed from the outside. The scroll bands can be labeled negatively (white writing on a black background) or positive (black writing on a white background), with negative labeling being easier to read in the dark, especially if the display consists of several bands, for example with multi-digit line numbers. However, all colors and different fonts and sizes are also possible for labeling .
Roll-up displays are attached to vehicles at least at the front, mostly also at the rear and on the sides, and sometimes also in the interior. A special form are double-sided displays that show information to both those waiting on the platform and passengers on board. Each position consists of two adjacent display fields, one on the inside and one on the outside. If such a roller band runs through, every second advertisement is upside down.
In order not to have to keep different variants of a conveyor belt within a transport company, it sometimes happens that certain travel destinations on the conveyor belt cannot be approached at all by certain cars in which it is installed for technical reasons. For example, some transport companies used the same conveyor belts for trolleybuses and omnibuses, whereby the former could only achieve the destinations provided with an overhead line due to their principle.
service
A roll-up display is changed by turning the reels either manually with a hand crank or by means of an electric motor that is controlled by the ticket printer or the integrated on-board information system (IBIS). With manual systems, the positioning is done by a number on the back of the tape, which can be seen through a window in the housing. With the first electronic solutions, the perforations in the tape were mechanically scanned by microswitches , which, however, was prone to failure and wear. More recent roller tape displays have an optical scanning of perforations or bar codes .
On the Lisbon tram , the drivers alternatively use small hand mirrors with handrails, which they hold out of the driver's cab at the end stops during the changeover process , in order to check when the conveyor belt has reached the desired position.
history
Tape ads have been around in London since the late 1920s. In Germany, the roller conveyor display was further developed in the 1960s by Carl Brose, the head of the now defunct Carl Brose GmbH in Wuppertal - Elberfeld , to an automatic roller conveyor with motorized control. Brose had successfully implemented the switch to matrix displays in the 1990s, but the decline was initiated due to incorrect restructuring measures. The company was integrated into Funkwerk AG as Funkwerk Infosystems GmbH in 2004 from its insolvency by way of an asset deal . Until 2009 there was a branch in Wuppertal under the name Funkwerk IT Karlsfeld GmbH . At the end of the year, the Wuppertal branch was closed and relocated to the Karlsfeld site. However, the company FM-Infosystems GmbH is located in the premises of the former branch, which offers services related to advertisements for Brose, Krüger, Infosystems etc. Otherwise, tape displays are still offered by Giebel, Lawo, Innotron, Gorba, Mobitec and McKenna Brothers, for example.
In the meantime, scrolling displays have been largely replaced by electronic matrix displays ( flip-dot , LED or LCD ). Today you can almost only find them on older buses , trolleybuses , trams , light rail vehicles, underground trains and S-Bahn vehicles. An exception is the bus network of the City of London, where the municipal directing organization Transport for London stipulates the use of conveyor belts for better readability.
Advantages and disadvantages
The biggest disadvantage of scrolling tape displays compared to matrix displays is that if changes are necessary, they have to be expanded and at least partially re-printed or extended, which is a significant cost factor, especially for larger transport companies with numerous lines and vehicles. In addition, it is often not possible to swap or change all bands at the same time on a certain key date, for example a timetable change with line changes. In many cases, new lines or destinations are therefore already printed on the tape at the planning stage. In addition, it happens that the conveyor belt is not adapted to the use of the vehicle and therefore the required travel destinations are missing. The different conveyor belts contain, for example, only the destinations of the lines served by the respective depot, so that the vehicle has to be signposted differently in the event of an unscheduled use on other lines.
In the case of more than 100 positions on a tape, a scrolling process can sometimes take longer than a minute. Therefore, some destinations are sometimes listed twice in order to shorten the changeover process. Matrix displays, on the other hand, allow dynamic, rapidly changing representations, so that, for example, the entire course of the line or special signs for special traffic can be displayed.
An advantage over matrix displays, on the other hand, is that scrolling displays also allow color displays and are easy to read in any light. For this reason, some transport companies, for example in Amsterdam and Freiburg im Breisgau , combine tape displays to display color-coded line numbers with matrix displays to display the destination.
lighting
To improve readability, for example in the dark, the roller tape can be illuminated from behind so that the light shines through the tape. For this purpose, one or more fluorescent tubes , previously incandescent lamps , are located behind the tape .
Illustrations
Unrolled tape of the Stockholm tram with some white blanks
Rolled out roller tape from a Zurich Mercedes-Benz O 405 GTZ , the perforations for automatic positioning can be seen to the right of the targets
Coding of the individual display positions on the Düsseldorf tram , there are a total of 60 positions, eight of which are blank. The indication special train is listed twice.
Destination displays sorted by lines on a historical trolleybus of the Lucerne trolleybus with intermediate turning points. Destination 17 for line 6, which opened in 1960, was added later. The mounting for the removable crank for moving the conveyor belt can be seen below the table
Opened conveyor belt box of the Zurich tram with side lighting by incandescent lamps
On the Wuppertal suspension railway , a special roller tape display underneath the windshield was used to display the course number , in this case course 4
A trolleybus in San Francisco with a two-part scrolling display for the line and destination. The right scroll band for the destination shows a special position for destinations not intended on the scroll band. The course number behind the windshield is also displayed on a multi-part scrolling display.
Tape display to show the train number on a British diesel locomotive
Stationary use
In the past, roller displays were also used as train destination displays for passenger information on the platforms of the stations. There they were superseded by leaflet advertisements that can change advertisements much faster, which in turn have largely been replaced by digital advertisements.
While conveyor belts hardly play a role in transport today, poster showcases with changing technology based on the same principle are increasingly being used for advertising purposes.
Rolling tapes of a price pole at a gas station, 2007
Train destination indicator at the Sarreguemines railway station , 2009
Web links
Individual evidence
- ↑ a b c d e Jürgen Pottharst: display, electromechanical . In: Elmar Schrüfer (Hrsg.): Lexicon of measurement and automation technology . Springer, Berlin / Heidelberg 1992, ISBN 978-3-642-95752-9 , pp. 27 f . ( google.de [accessed on January 29, 2019] First edition: VDI-Verlag, Düsseldorf 1992).
- ↑ Passenger information system at www.tram-bus-bern.ch
- ↑ ola-portugal.net, accessed on January 29, 2019