Escalator system

In order to improve safety, an escalator system is configured to drive an escalator in response to a signal received from a user interface located in a first end of the escalator, and to stop movement of the escalator in response to detection of opening of an access cover plate in a second end of the escalator.

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates an escalator system and in particular to a solution for improving the safety of an escalator system.

Description of Prior Art

Previously there is known an escalator system with a first pit in a first end of the escalator and with a second pit in a second end of the escalator. Various technical devices needed for driving the escalator are arranged in the first pit and the second pit. Consequently service technicians need to have access to the first and second pit. This access is provided such that the service technician is able to access the first and second pit by opening the access cover plate covering the first or second pit, depending on to which pit access is needed.

A safety risk is involved in working with the devices arranged in the first and second pit. One safety risk relates to the motor and to the moving parts needed to drive the escalator. In case the service technician comes into contact with the moving parts while the escalator is driven, the risk is that a part of the body of the service technician is jammed between moving parts. In order to prevent such injury, known escalator systems are provided with detectors that prevent driving of the escalator in a normal (or automatic) mode while the first or second access cover plate covering the first and second pits is open.

However, the first and second pit are both provided with a user interface which makes it possible for the service technician to drive the escalator in an inspection mode from the first and second pit. The escalator can be driven in inspection mode also when one or more access cover plates is open. This involves a safety risk, in particular when two service technicians work on the same escalator simultaneously. In praxis escalator systems are occasionally implemented in such a way, that a service technician working in a first end of the escalator cannot see the other end of the escalator and is therefore not aware of what the service technician working in the second end is doing.

If in a known escalator installation a service technician working in a first end of the escalator starts to drive the escalator in the inspection mode at the same time as the service technician in the second end opens the access cover plate and enters the second pit where he comes into contact with moving parts, there is a significant risk of injury.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a solution which improves safety of an escalator system. This object is achieved with an escalator system according to independent claim1and with a method according to independent claim8.

A solution where movement of the escalator is stopped in response to detection of opening of an access cover plate in a second end of the escalator improves the safety of the escalator.

Preferred embodiments of the invention are disclosed in the dependent claims.

DESCRIPTION OF AT LEAST ONE EMBODIMENT

FIGS. 1 to 3illustrate an embodiment of an escalator system1. A first end2of the escalator is provided with a first pit3and a second end4of the escalator is provided with a second pit5. As illustrated by way of example inFIG. 1, the first end2and the second end4of the escalator may be arranged on different floors of a building, for instance. However, in that case the first end is not necessarily the lower end, as illustrated in the figures by way of example, but it is also possible that the first end is the upper end of the escalator. Alternatively the first end and the second end of the escalator may be both arranged on the same floor, in which case the escalator can be used for transporting persons from one location to another while remaining on one single floor.

FIG. 2illustrates the first end2of the escalator with a first access cover plate6in a closed position, in other words in a position where the first access cover plate6covers the first pit3in such a way that persons using the escalator are prevented from falling into the first pit3. InFIG. 1the first access cover plate has been removed and is not illustrated at all. Consequently, the first access cover plate6is in an open position which allows access to the first pit3and to the devices7which are located in the first pit3. The second access cover plate8in the second end4of the escalator is inFIG. 1illustrated in a closed position.

A frame9of the escalator is provided with a control panel10. Via this control panel the escalator can be driven in a normal operation mode, also referred to as an automatic mode. Consequently, a person responsible for operating the escalator can during daily use via this control panel stop the escalator and also control it to run in a first direction (such as upwards) and in a second opposite direction (such as downwards). In case the escalator system detects that the first access cover plate5or the second access cover plate is in an open position, the escalator system prevents driving of the escalator in the normal mode.

The first pit3at the first end of the escalator is provided with a user interface11. A similar user interface may be provided also in a second pit5at the second end4of the escalator. This user interface may by implemented with one or more pushbuttons, as a touch screen or as an inspection mode input comprising an electric socket to which a service technician may connect a portable operating panel, for instance. In any case via the user interface11the service technician can provide signals to the escalator system to drive the escalator in an inspection mode. The escalator system, which may comprise a control unit controlling an electric motor which in praxis drives the escalator, is configured to allow driving of the escalator in inspection mode also in a situation where first access cover plate6is in an open position. One alternative is that the user interface11is deactivated until the service technician removes a blind plug. This removal activates both the user interface for driving the escalator in inspection mode and also a stop switch.

FIG. 3illustrates the second pit5in cross section. For simplicity, the devices contained in the second pit are not illustrated inFIG. 3. In the illustrated example the second pit5is provided with a detector12detecting the position of the second cover plate8. InFIG. 3it is by way of example assumed that the detector12is implemented as a weight switch with a moving part13moving downwards into the body of the weight switch once a part of the weight of the second cover plate8comes into contact with the moving part13. Consequently, the detector is able to detect whether the second cover is in an open position or in closed position. The escalator system is configured to stop movement of the escalator in response to detection of opening of the second cover plate8. For this purpose the detector12may be a simple switch which via braking and closing an electric circuit informs the control unit of the escalator system of the position of the second cover plate8. Alternatively, the detector12may be implemented with circuitry capable of communicating the position of the second cover plate8to the control unit via a computer bus, according to the PESSRAE standard, for instance.

One alternative is that the escalator system is configured to, after having stopped driving of the escalator in inspection mode, allow continued driving of the escalator in inspection mode provided that signals received from the user interface11indicate that the user has pressed the correct button to continue driving of the escalator. In this way, the first service technician in the first end2of the escalator who is driving the escalator in inspection mode via the user interface will notice that a second service technician has opened the second access cover plate8due to the fact that the escalator stops. However, immediately after this, in case the first service technician determines it safe and appropriate, the first service technician has the possibility of continuing driving of the escalator. In this way information about the possible safety hazard is efficiently provided to the first service technician, however, in such a way that it does not delay the work of the first service technician more than absolutely necessary.

FIG. 4illustrates a detector12′ which can be used in the escalator system ofFIGS. 1 to 3instead of the detector12illustrated inFIG. 3.

The detector12′ ofFIG. 4is provided with a spring14′ which can be bent sideways. When the access cover plate8is in closed position, the access cover plate8is in contact with this spring14′ such that it is bent sideways, and once the access cover plate is in an open position the spring force returns the spring to the illustrated straight upright position. The spring is provided with electrical contacts indicating the position of the spring such that the escalator system can be provided with information about the position of the access cover plate8, as previously explained.

In the above explanations and in the figures it has for simplicity been explained that the first pit is provided with the user interface and the second pit is provided with a detector detecting the position of the second access cover plate. However, in practical implementations both the first pit and the second pit are naturally provided with both a user interface and a detector detecting the position of the respective access cover plate. In this way sufficient safety can be ensured, as irrespectively in which end of the escalator a service technician drives the escalator in inspection mode while a second service technician opens the access cover plate in the opposite end of the escalator, the escalator system detects this and stops the escalator.

It is to be understood that the above description and the accompanying figures are only intended to illustrate the present invention. It will be obvious to a person skilled in the art that the invention can be varied and modified without departing from the scope of the invention.