Apparatus for cleaning the steps of an escalator

An apparatus for cleaning escalator steps having grooved front surfaces cleans during the operation of the escalator. A brush extending across the entire width of each step is positioned under the rear edge of the tread. The bristles of the brush press against the front surface of the adjacent step when the steps are in predetermined regions of the escalator. The relative motion of the steps as they move from the horizontal to the inclined and back to the horizontal regions creates a relative vertical motion between the brush and the front surface for the cleaning of the front surface. The front surface thus is cleaned twice per revolution of the step conveyor by being moved against the brush bristles, once from top to bottom and once from bottom to top, practically across the entire height of the step.

BACKGROUND OF THE INVENTION 
The present invention relates generally to escalators and, in particular, 
to an apparatus for cleaning the steps of an escalator as the escalator is 
operating. 
If relatively long intervals are scheduled for the periodic cleaning of 
escalators. the treads and front surfaces of the steps, both of which have 
ribs and grooves formed thereon, tend to collect dirt sediment which 
requires additional or more frequent cleaning operations. A portion of the 
dirt which is deposited on the steps is dumped automatically into dirt 
hoppers at the upper or lower return regions, especially in dry weather 
and depending on the direction of travel of the escalator Another portion 
of the dirt, however, can be deposited in the grooves and can only be 
removed with difficulty For this reason, various devices for the cleaning 
of escalators in particular for the steps of escalators, have been 
constructed and utilized with some degree of success. 
German Patent Application No. 37 04 388 shows cleaning equipment for the 
steps of escalators which is provided as an independent, portable unit The 
cleaning equipment consists of a supporting bracket with a rocker bar 
carrying an electric motor and a rotatably supported brush roller driven 
by a V-belt. Additionally, in the immediate vicinity of the brush roller, 
a suction device can be provided for removing the brushed-off dirt. The 
cleaning equipment with its supporting bracket is placed, for example on 
the lowest step of a stopped escalator. The rocker bar with the brush 
roller is directed against the higher adjacent step The motor is turned on 
and the rotating brush roller is pressed manually onto the front surface 
of the adjacent step with the aid of the rocker bar The brush roller is 
moved upward on the step and guided over the horizontal tread. In this 
way. the grooved front surface and the grooved tread of the step are 
cleaned by the brush roller which extends to the bottom of the grooves and 
the brushed-off dust is removed by suction. For the cleaning of the next 
step, the cleaning device is placed on the cleaned tread and again the 
next higher adjacent step is cleaned. The process is repeated until all 
visible steps of the escalator are cleaned. In order to clean all steps of 
the escalator, the step belt is moved forward by stages through temporary 
switching-on of the escalator and cleaned as described earlier until all 
steps of the escalator have been cleaned. A drawback of this device is 
that the relatively unwieldy cleaning equipment is required, which device 
must be dragged or pulled around on the escalator, that the cleaning can 
only take place when the escalator is not operating and that there exists 
a certain danger of accidents if during the moving forward by stages of 
the step conveyor, the cleaning equipment remains placed on a step and is 
not removed from the escalator A further drawback is the fact that a 
certain region on the inner edge between the tread and the front surface 
of an adjacent step cannot be reached by the round brush roller and, 
therefore, cannot be cleaned adequately. 
German Patent No. 30 16 597 shows another device for cleaning the steps of 
an escalator which device is permanently built into a return point of the 
escalator. The cleaning device consists of an adjustable base frame with a 
carrying device supported on rails and a fixed cleaning brush. By force of 
springs, the cleaning brush is pressed against the passing steps at the 
return point and the tread of each step is continuously brushed and 
cleaned while the escalator is operating. A disadvantage of this cleaning 
device is that the front surfaces of the steps cannot be cleaned because 
the front surfaces are not easily accessible in the region of the return 
points. 
It is an object of the present invention to provide an escalator cleaning 
device which continuously cleans every front surface of the steps as the 
escalator continues to operate. 
SUMMARY OF THE INVENTION 
The present invention concerns an apparatus for cleaning the steps of an 
escalator including a brush adapted to be attached to an escalator step 
below a rear edge of the step. The brush has bristles adapted to extend 
across the width of and into contact with a front surface of an adjacent 
escalator step. The bristles can be shaped to match the shape of the ribs 
and the grooves formed on the front surface of the adjacent step. The 
brush can be slidably mounted in a holder for adjustment with respect to 
the front surface of the adjacent step to be cleaned. 
An advantages of the present invention is that every grooved front surface 
of the steps in an escalator is cleaned while the escalator is operating. 
It is, therefore, not necessary to stop the escalator and to clean during 
the off or non-operating time with the aid of portable cleaning devices. A 
further advantage the present invention is that no additional personnel 
are required since the cleaning of the front surfaces of the steps is 
automatic. Another advantage is that since the cleaning is performed 
continuously, immediately after soiling the steps are cleaned thereby 
preventing sticking of dirt on the front surfaces.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the FIGS. 1 and 2, a step is designated with 1. Each step 1 includes a 
tread 1.1 and a front surface 1.2. The tread 1.1 and the front surface 1.2 
have a plurality of grooves such as grooves 1.4 and 1.6 respectively 
formed between spaced apart, generally parallel ribs 1.5 and 1.7 
respectively as shown in FIG. 2. Meshing into the grooves 1.6 of the front 
surface 1.2 of each of the steps 1 is a toothed edge 1.8 formed at the 
rear of the tread 1.1 of the adjacent step 1. Positioned under the rear 
edge of the tread 1.1 is a brush 2 which has bristles 3 extending across 
the width of and toward the adjacent front surface 1.2. The bristles 3 can 
be the same length or can be shaped to match the shape of the front 
surface 1.2 for sweeping the grooves 1.6 and the ribs 1.7 of the front 
surface of the adjacent step 1. The brush 2 can be solidly clamped in a 
holder 4 fastened on the step body, or alternatively be slidably 
supported, as shown in FIG. 2, for adjustment with respect to the front 
surface 1.2. The arrows 5 in FIG. 1 indicate the direction of movement of 
the step conveyor, while the arrow 6 indicates the relative motion of the 
steps 1 which assure the horizontal position of the tread 1.1 in the 
inclined region of the escalator. 
In the FIG. 3, the step conveyor is designated with 7 and is formed of a 
plurality of the individual steps 1. The step conveyor 7 has an upper 
reversal region 8 and a lower reversal region 9 at opposite ends connected 
to horizontal return regions connected at opposite ends of inclined 
regions. At the upper reversal region 8 and/or at the lower reversal 
region 9. blower devices 10 can be positioned to remove dirt loosened by 
the brushes 4. 
The cleaning equipment described above operates in the following manner: 
The brush 2 attached below the rear of the tread 1.1 of each step 1 is 
directed. during the assembly of the step 1 into a step conveyor, against 
the front surface 1.2 of an adjacent step 1 with an initial stressing 
force. If the step is assembled in the inclined region of the step 
conveyor which is visible during operation. the brush 2 is already lying 
against the front surface of the adjacent step. If the step is assembled 
in the region of the upper or lower reversal regions, there is no contact 
between the brush and the front surface of the adjacent step. In the 
return regions between the upper and lower reversal regions, the brush and 
the front surface again press against each other, but no relative vertical 
movement combined with a cleaning action takes place. During the downward 
travel in the inclined region, the same relative movements and cleanings 
of the front surfaces result as during the upward travel, but in reverse 
sequence and direction. The front surface of each individual step is thus 
brushed and cleaned during operation twice in each escalator cycle. 
As stated above, a blower device 10 directing air on the front surfaces 1.2 
of the steps 1 and/or on the brushes 2 can be provided at the upper and/or 
the lower reversal regions of the step conveyor. The blower device 10 
blows away any released dirt and dirt which has not dropped off during the 
return motion of the step conveyor before the step returns to the visible 
regions of the escalator. 
Thus, the cleaning equipment according to the present invention is useful 
as a supplement to a cleaning device which serves only for the cleaning of 
the treads of the steps. 
In accordance with the provisions of the patent statutes, the present 
invention has been described in what is considered to represent its 
preferred embodiment. However. it should be noted that the invention can 
be practiced otherwise than as specifically illustrated and described 
without departing from its spirit or scope.