Note: Descriptions are shown in the official language in which they were submitted.
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Title: METHOD OF APPLYING AND REMOVING A PROTECTIVE FILM
TO THE SURFACE OF A HANDRAIL FOR AN ESCALATOR OR MOVING
WALKWAY
FIELD OF THE INVENTION
This invention relates to handrails for escalators and
moving walkways, and more particularly is concerned with applying a
protective film, optionally including advertising or other visible material,
to the surface of such a handrail.
BACKGROUND OF THE INVENTION
Advertisers continually seek out new locations to place
advertisements. It has been recognized for sometime that various forms of
mass transit and the like offer good opportunities for advertising.
Necessarily, mass transit systems offer a large potential audience, and a
relatively small number of well positioned advertisements can be seen by a
large number of people. Travelling on mass transit is usually fairly
time-consuming and hence travellers of such systems often have plenty of
time to view and read advertisements, which also make such advertising
attractive to businesses. This has been well recognized in the past, and
advertisers have sought various locations for placing advertisements.
Escalators and moving walkways are a common
component of many mass transit systems, and are also found in numerous
other locations with a high level of pedestrian traffic, e.g. large office
buildings, shopping malls, large stores and the like. While travelling on an
escalator is relatively quick compared to, say, a subway journey, an escalator
ride nonetheless presents a potential audience for advertisers. While a ride
on an escalator is relatively short, it is certainly long enough for a rider
to
notice and read an advertisement. Moreover, it is not really practical for an
escalator rider to do anything else while riding the escalator, such as read a
book or newspaper.
Advertisers have long recognized this, and it is common
on well-used escalators to find various advertising panels. Thus,
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conventional poster advertising is often found lining the wails of escalator
shafts. Additionally, advertisers have sought to place smaller, poster-like
advertisements on smaller panels on top of the strip separating balustrades
of up and down escalators. ~..".ommoniy, advertisements would be placed on
both sides, so as to present advertisements to riders on bath the up and
down escalators.
Ingenious advertisers have sought other ways of
advertising on escalators. Thus, it has accurred to others that advertising
could be placed on escalator handrails. 'This is attractive, since an
escalator
handrail presents an otherwise unused surface. As for grasping any object, a
rider cm an escalator will instinctively first look at the handrail to locate
it.
This ensures that the handrail, more often than not, will be at least glanced
at by each user or rider. This makes it attractive for simple advertising,
e.g.
well known company logos and other advertising devices.
Thus, published Japanese application 57-130883 discloses a
proposal for providing individual decals or stickers intended to be placed at
regular intervals on an escalator handrail. These stickers include some sort
of adhesive and a first film, and print ink applied to the rear of the first
film.
The disadvantage with this proposal is that it requires each
of these stickers or decals to be placed individually and discretely on the
handrail. This is difficult, time-consuming and care would be needed to
ensure that they are accurately and uniformly aligned. Moreover, each
individual sticker would present a number of edges which could be caught,
tending to remove it. Thus, its forward and trailing edges would present
edges which could be readily caught by elements of the handrail drive
mechanism. It would be appreciated that accidental removal of an adhesive
sticker by the drive mechanism, so that the sticker then becomes entangled
in the drive mechanism, is highly undesirable. Additionally, these edges,
together with side edges of the decal would be readily visible to users, and
it
is believed that many users or riders of an escalator would, either
deliberately, or absentmindedly, tend to pick at these edges and lift them up.
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This would either tend to remove each sticker or render it more susceptible
to accidental entanglement in the drive mechanism.
An alternative proposal is found in Canadian patent
1,304,035 and the equivalent U5 patent 5,020,256 (Andrew B. French). This
proposes a relatively complex constrc,cction which would require wholesale
redesign of the structure of an escaiator handrail. It proposes a handrail
provided with some sort of a slat or the like and a transparent cover.
Advertising material is than placed between the transparent cover and the
main body of the handrail. 'This would, in theory, overcome some of the
disadvantages of the Japanese proposal. Unfortunately, this proposal totally
fails to address the structural requirements of an escalator handrail. A
handrail is subjected to considerable stresses and strains, and one cannot
simply remove substantial sections of the handrail cross-section without
addressing the structural considerations.
For example, a transparent cover could be subject to
substantial tensile and Jor compressive stresses, depending on the drive
mechanism, and this issue is not addressed. Necessarily, this proposal
requires complete replacement of each escalator handrail with one
according to this invention, if advertising is to be applied.
French patent 2,72$,377 discloses a vinyl film for use in
store check-out conveyors. The vinyl film contains advertising and is for
advertising to consumers as they pass through the check-out.
SUMMARY OF THE INVENTION
a'.5 A further consideration is that in many situations it may be
desirable simply to provide some form of protective cover to an escalator
handrail, and this is not addressed by any of the prior art proposals outlined
above. First, many escalator handrails, after a period of use can develop a
dull, worn appearance. Additionally, they may accidentally have various
marks or discolourations on the surface, due either to the drive mechanism
or the actions of users. For some situations, eg. in luxury hotels, resorts
and
the like, it is desirable that escalator handrails present a good appearance.
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Refinishing the surface of a handrail is not practical. It is therefore
desirable
to provide some way of applying some sort of a film to an escalator
handrail, which can present a new appearance or finish to the handrail.
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Accordingly, it is desirable to provide a film which can be readily
applied in situ to an escalator handrail. Such a film should be capable of
providing one or both of: a new, refinished appearance to the handrail; and
advertising messages or logos.
Preferably, the film should be capable of application readily and
simply, with minimum interruption in normal operation of the escalator. This
should be achievable without requiring removal or replacement of the
handrails.
Additionally, the inventors have realized that this covering
should be sufficiently continuous, so as to minimize edges, etc which can
promote accidental removal or entanglement in the drive mechanism. Further,
this should be such as to minimize the opportunities for users to remove the
surface finish or covering.
The invention is based on the concept of providing a film to the
surface of the handrail, which film is both continuous and is removable.
In accordance with a first aspect of the present invention, there
is provided a flexible film for applying to a handrail. The handrail may be a
moving handrail, such as on a moving sidewalk or escalator handrail or a
stationary handrail, such as would be found in a stairwell. This film
comprises
a first film layer with a first layer of adhesive on the underside of the
first layer,
and is characterized in that the film includes a second layer of adhesive
bonding a second film layer to the top of the first film layer. The film is
elongate, i.e. substantially continuous and of a uniform width adapted for
mounting to a handrail. This film may optionally include a layer of printed
matter on top of the first layer. A release sheet layer of the same width as
the
film may optionally be included to protect the first adhesive layer. The first
and
second layers preferably comprise polyurethane with a thickness of 0.076 mm
(3 mil) and the adhesive layers comprise an acrylic-based adhesive with a
thickness of 0.025 mm (1 mil).
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In accordance with related application 2,265,028, there is
provided an elongate handrail in combination with a flexible film as described
above. Where the handrail is a moving handrail, the end portions of the film
may overlap one another to form a spliced joint. The film may extend around
the handrail and cover part of the shoulder of the handrail. For a fixed or
stationary handrail, the ends of the film can simply wrap around ends of the
handrail, so as not to be readily visible to a user.
In accordance with a second aspect of the present invention,
there is provided a flexible film for applying to a handrail, the film
comprising:
a first film layer; a first layer of adhesive on the underside of the first
film layer
for adhering the film to a handrail, wherein the film has a width
corresponding
to a handrail and is elongate, whereby the film can be cut to fit a selected
handrail, and characterized in that the film includes means for collecting
contaminants from a moving handrail and associated drive mechanism.
In accordance with related application 2,377,641, there is
provided an apparatus for applying an adhesive film to a moving handrail, the
apparatus comprising: mounting means for mounting the apparatus to a
balustrade; a first spindle means, for mounting a first roll of film; and a
pressure means for applying pressure to the film to cause the film to adhere
to
the handrail, whereby, in use, the handrail can be driven past the apparatus,
causing the film to be unrolled from the first roll with the means for
applying
pressure causing the film to adhere to the handrail.
It is possible that the adhesive used will not require a release
sheet, and that the film could be unwound in the same manner as many
commercially available adhesive tapes. Where the nature of the adhesive
does require a release sheet, the apparatus may further comprise a second
spindle means and a second roll for taking up a release sheet is mounted on it
in use, and a drive means between the first and second spindle means. The
unwinding of a film from the first spindle then causes the drive means to
drive
the second spindle which takes up a release sheet separated from the film
leaving the roll. The drive means may comprise a gear train. The gear train
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can include a ratio of speeds between the first and second spindle such that
the second spindle means is driven at a faster speed than required to take up
the release sheet. The apparatus then includes clutch means on at least one
of the two spindle means to ensure that the tension does not become too
great so as to cause the release sheet to snap, and this can then maintain a
uniform tension in the release sheet.
The apparatus may include a longitudinally extending member
as a main body of the actual application for applying the film, and the first
and
second spindles may be attached to a swing arm pivotally mounted on the
longitudinally extending member. A main roller may be included in the means
for applying pressure and pivotally mounted with respect to the main body.
The main roller may be biased against the top of the escalator handrail by
means of a spring.
The adjustment means may comprise pivot and sliding
connections.
The means for applying pressure may include a pressing
mechanism including a plurality of rollers mounted symmetrically about the
centre line of the means for applying pressure corresponding to a centre line
of a handrail. The rollers may extend from the forward end of the pressing
mechanism (the forward end corresponding to the forward motion of the
handrail) to the rearward end of the roller means. The pair of rollers at the
rearward end of the roller means are mounted adjacent to the centre line of
the apparatus and the successive pairs of rollers are mounted progressively
further apart. As the moving handrail is passes through the pressing
mechanism, the film is progressively wrapped around the outer surface of the
handrail.
Also in accordance with related application 2,377,641, there is
provided an apparatus for removing an adhesive film from a moving handrail,
the apparatus comprising:
mounting means for mounting the apparatus to a balustrade;
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a first spindle means for mounting a take-up roll;
a drive cylinder pivotally mounted to the apparatus;
means for pressing the drive cylinder against a handrail, to
receive a drive input when the handrail is in motion;
transmission means connecting the drive cylinder to the first
spindle means, for driving a take-up roll mounted on the first spindle means
to
wind up a film from the handrail.
Related application 2,377,641 also provides a method of
applying a flexible film to a moving handrail, the method comprising:
(1) providing a film comprising a first film layer and first layer
of adhesive on the underside thereof, the film being generally elongate and
having width corresponding to the width of the handrail;
(2) aligning and adhering a first end of the film to a surface of
the handrail;
(3) driving the handrail relative to the film, to cause the film to
adhere continuously and progressively to the handrail; and
(4) ensuring that the full width of the film is uniformly and
smoothly adhered to the surface of the handrail.
The method may include providing the film on a roll and
mounting the roll on a spindle adjacent to the handrail. A roller may then be
applied to the surface of the handrail to press the film against the handrail.
The method may further comprise progressively wrapping the film around the
lips of the handrail by means of pairs of rollers mounted further apart around
the outside of the handrail. The method may further involve the use of an
apparatus as described in the third aspect of this invention.
Further in accordance with related application 2,377,641, there
is provided a method of removing an adhesive film mounted on a handrail, the
handrail being mounted for movement relative to a balustrade, and the
method comprising:
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(1 ) mounting an apparatus to the balustrade including a drive
cylinder and a spindle for a take-up roll;
(2) mounting a take-up roll on the spindle and pressing the
drive cylinder against the surface of the handrail;
(3) manually detaching an end portion of the adhesive film
and engaging the end portion with the take-up roll;
(4) driving the handrail, thereby to transfer drive to the drive
cylinder, and in turn to cause rotation of the take-up roll to wind up the
adhesive film;
(5) after the entire adhesive film has been removed from the
handrail, stopping the handrail and removing the roll with the wound up
adhesive film from the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention and to show
more clearly how it may be carried into effect, reference will now be
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made, by way of example, to the accompanying drawings which show the
preferred embodiment of the present invention and in which:
Figure 1 is perspective view of an apparatus in accordance
with the present invention for applying a film to an escalator handrail;
Figures 2a and 2b are side views of the apparatus of Figure
1, in different positions;
Figures 3a and 3b are views along the length of a handrail,
showing alternative mounting arrangements;
Figure 4 is a perspective view showing the apparatus in use
on a balustrade of an escalator corresponding to figure 3a;
Figure 5 is a perspective view showing the detail of motion
of the film and a release sheet showing application of film to an escalator
handrail;
Figures 6a and 6b are detailed views of a spindle for
mounting a roll, for either the film or the release sheet;
Figures 7a, 7b and 7c are schematic views showing paths of
the film and release sheet and wrapping of the film around the handrail;
Figures 8a and fib are cross-sectional views through a
pressing mechanism, showing operation thereof;
Figure 9a-9f are further cross-sectional views through a
pressing mechanism, showing mounting of pressing rollers;
Figure 10 is a side view of the pressing mechanism,
showing details of one-half of the trough-shaped pressing mechanism;
Figures lla-11f are views showing details of the spacing
mounting of the rollers of the pressing mechanism;
Figure 12 is a cross-sectional view through a film according
to the present invention;
Figure 13 is a perspective view of a mechanism for aligning
the apparatus of the present invention;
Figure 14 shows a perspective view of an apparatus for
removing a film from a handrail, the apparatus being shown in use on a
handrail;
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Figures 15a, 15b and 15c show, for part of the apparatus for
removing a film of Figure 14, a perspective view from the other side, a side
view and a perspective view similar to Figure 14, all on an enlarged scale;
Figure 16 shows a sectional view through the apparatus of
14 and 15; and
Figure 17a-17d show plan views of examples of perforation
patterns for a film for a handrail.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to Figures 1 and 3a, an apparatus in
accordance with the present invention is indicated generally by the
reference 10. The apparatus 10 includes a main support member 12, of
tubular, square cross-section. The support member 12, at its lower end is of
inverted T-shape and includes two downwardly extending portions 14 of
different lengths. At the lower end of each portion 14, there is mounted a
suction cup 16. If required, the support member 12 can be offset laterally
(Figures 3a, 3b), to locate the apparatus in the desired position relative to
a
handrail.
At the upper end of the support member 12, there is a pivot
connection 18, providing a connection to a first cross member 19. In known
manner, the pivot connection 18 includes overlapping flanges secured to
the members 12, 19, and a nut and bolt adjustable to clamp the flanges
together.
Mounted on the first cross member 19 is a sliding swivel
joint 20 which includes a bracket slidable along the first cross member 19. A
threaded screw member 21 enables this bracket to be clamped relative to the
cross member 19.
The bottom end of the bracket of the swivel joint 20
includes a second pivot connection 22 to a second cross member 23.
Similarly, this pivot connection 22 can be locked or secured by means of a
nut and bolt arrangement. A downwardly extending member 24 extends
from one end of the second cross member 23.
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The overall arrangement of the members 12, 19, 23 and 24,
the pivot connections 18 and 22 and the sliding swivel joint 20 is to provide
desired degrees of freedom for the lower end of the downwardly extending
member 24, both vertically and horizontally, i.e. in the plane of Figures 3a
and 3b. As the actual applicator of the present invention (to be detailed
below) is mounted at the lower end of the member 24, this enables the
applicator to be adjusted to a desired location relative to a handrail. Thus,
the pivot connections 18, 22 enable the vertical location to be adjusted, and
this adjustment will necessarily cause some lateral or horizontal
movement of the lower end of the downwardly extending member 24. The
sliding joint along the cross member 19 enables the horizontal location to be
adjusted.
Figures 1 and 3a show one mounting arrangement, in
which the cross members 19, 23 have their free ends extending in general
opposite directions. In an alternative mounting arrangement the vertically
oriented members 12, 24 are located close together, with the free ends of the
cross members extending in the same direction away from the members 12,
24.
In general, the apparatus will always be mounted on the
inside surface of a balustrade 198, and often, the balustrade will not present
an accessible outer surface. Thus, both the arrangements of figures 3a and 3b
will be required for the two handrails on either side of an escalator or
moving walkway.
The lower end of the downwardly extending member 24 is
connected to a longitudinally extending member 32 (this is described as
longitudinally extending, in relation to the escalator handrail, as will
become clear from the description below), which forms a main body of the
actual applicator for applying the film.
A rearward end of the member 32 is secured to an L-shaped
bracket 34. Further cross members 36, 37 extend perpendicularly out from
the longitudinally extending member, at the middle and forward end
thereof. A projecting lug 38 is mounted on and extends upwardly from the
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longitudinally extending member 32, between the cross members 36 and 37.
The L-shaped bracket 34 includes a horizontal element 40.
A rear roller 41 is mounted on two lugs 41a extending downwards from the
rearwards end of horizontal element 40. A small frame 42, comprising a
pair of parallel and spaced side members and joining cross member, is
pivotally mounted to two small lugs 44 projecting upwardly and forwardly
from the front end of element 40. A roller 46 is rotatably mounted between
the free ends of the side members of the frame 42.
Referring now to Figures 1, 2a and 2b, to bias the frame 42,
and hence the roller 46, downwards, there is provided a spring mechanism
47 mounted to a vertical element 50 of the L-shaped bracket 34. The spring
mechanism 48 includes a helical coil spring 48a (Figure 1), a plunger 52 and
upper and lower discs 49a and 49b. The plunger 52 is pivotally connected at
its lower end to a side projection from the frame 42. The bottom of the
helical coil spring abuts the lower disc 49b, while the top end of the spring
48a abuts the upper disc 49a. The lower disc 49b is fixably mounted to
plunger 52, while the upper disc 49a is slidably mounted on the plunger.
The upper disc 49a is also pivotally attached to a vertically-directed crank
member 54. Crank member 54 is attached via a crankshaft (not shown) to a
horizontally-directed handle 56 on the opposite side of vertical element 50,
with the crankshaft rotatably mounted in a bore of the element 50. When
handle 56 is horizontal and pointing rearwards (as in Figure 2b), the crank
member 54 is pointing downwards, compressing the spring 48a. The
compression of the spring 48a biases frame 42 downwards. Handle 56 is kept
in place by means of ratchet 58. When the ratchet is released and handle 56
is rotated to a forward-pointing horizontal position, crank member 54 is
pointing upwards, releasing the compression in the spring (as in Figure 2a).
The ratchet 58 is pivotally mounted in an opening in the vertical element
50, so that it can be displaced away from the handle 56, to release the
handle.
A swing arm 60 is pivotally mounted to the projecting lug
38 and includes a spacer element 62, so as to space the swing arm away from
the longitudinally extending member 32, for reasons which will become
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clear below. Swing arm 60 may comprise two separate members 60a and 60b
fixably attached via a joint 61. Swing arm 60 may be locked into a horizontal
position as shown in Figure 2a by means of a simple locking mechanism 63.
Locking mechanism 63 is a simple L-shaped member where one end is
pivotally mounted on longitudinally extending member 32. The other end
abuts the bottom portion of the swing arm preventing the arm from falling.
Swing arm 60 may be unlocked by pivoting the locking mechanism 63 away
from swing arm 60.
First and second spindles 64, 66 are rotatably mounted to
the swing arm 60, and details of the spindle 66 is given below in relation to
Figures 6a, 6b.
The first spindle 64 is secured to a drive gear 68, while the
second spindle is secured to a driven gear 70. An idler gear 72 is rotatably
mounted to the swing arm, _ so as to engage both the drive and driven gears
68, 70. The drive gear 68 is substantially larger than the driven gear 70, so
as
to ensure that the second spindle 66 is driven at a faster speed than that of
the first spindle 64.
The arrangement of the spindles 64, 66 and the roller 46 is
intended to apply an adhesive film to the top surface of the handrail. To
ensure that the film is applied uniformly around the side edges and at least
partially underneath a handrail, ~ pressing mechanism 90 is provided. The
pressing mechanism comprises a trough-shaped element 92 having first
and second halves 92a, 92b. Each of the element halves 92a, 92b includes
elements 94 that combine to form shallow slots or sleeves. Extending
downwardly from each of the cross members 36, 37 is a support member 96
having, in cross-section inverted T-shape, so as to present edge portions
engaging the sleeves formed by the elements 94. This mounts the
trough-shaped element halves 92a, 92b, for sliding movement laterally,
while otherwise limiting their movement.
As best seen in Figures 1, 8a and 8b, an over-centre
mechanism 100 comprises a first arm 101 and a second arm 102 pivotally
mounted to the trough-shaped element halves 92a, 92b respectively. The
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second arm 102 forms an obtuse angle and is formed from two generally
parallel side members. The free end 104 of the second arm 102 provides an
actuating handle. The first arm 101 is pivotally attached to the second arm
102, generally at the obtuse angle therein. In known manner, if the handle
end 104 is raised and pivoted towards the longitudinally extending member
32, this causes the trough-shaped elements 92a, 92b to slide apart along the
inverted T-shaped member 96 (Figure 8b). When the handle end 104 is
displaced to the position shown in Figure 8a, then the trough-shaped halves
92a, 92b are drawn together to the position shown. The first arm 101
includes a nut 105 and bolt 105a assembly as shown in Figures 8a and 8b.
The nut 105 is used to shorten the first arm 101. The shortening of the first
arm 101 causes trough elements 92a and 92b to come closer together when
in the closed position. This enables adjustment of the width of the trough
92 for handrails of different dimensions.
Referring now to Figures 1, 9a-9f, 10 and 11a-11f, a series of
rollers 110, 111, 112, 113, 114, and 115 are rotatably mounted on roller
mounting mechanisms inside each of the element halves 92a, 92b. Rollers
110-115 are mounted such that the rollers 110 are relatively close to the
centre line of the apparatus and to the centre line of the handrail. Rollers
110 are mounted towards the rear of the element halves 92a and 92b at
position 110a (Figure 10). The other rollers 111, 112, 113, 114, and 115 are
located progressively further away from the centre line and progressively
closer to the front of the mechanism at positions 111a, 112a, 113a,114a, and
115a respectively, for progressively wrapping a film around the handrail.
Rollers 110 to 113, shown generally as 210 on roller mounting mechanism
212 (Figures 11a, 11d), are mounted on a frame 214. The frame 214 comprises
two side members 216 and three cross members 218, 220 and 222. The roller
210 is rotatably mounted on cross member 218. The frame 214 is pivotally
mounted on two lugs 224 extending from the base 226 of roller mechanism.
A helical torsion spring 228 is mounted on cross member 222. One end of
the spring is pressed against the base 226 and the other end is pressed
against
cross member 220. Spring 228 thus acts to bias frame 214 and roller 210
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inwardly towards handrail 200. The base 226 is mounted to a respective
trough-shaped half 92a, 92b.
Referring mainly now to Figures 11b, 11c, 11e, and 11f,
rollers 114 and 115 are similarly mounted within roller mounting
mechanisms with some exceptions. First, rollers 114 and 115 have smaller
diameters than rollers 110-113. As well, rollers 114 and 115 are spaced
laterally away from spring 228 with spacing elements 230. Both of these
differences are designed to allow the rollers to press the film against the
shoulder of the handrail where space is limited.
As best shown in Figures 2, 9e, 9f and 10, the trough-shaped
element halves 92a, 92b include a forward extension 116. Mounted to each
of these extensions 116 are brackets 118 and 119. Rollers 114 are rotatably
mounted to the first brackets 118 and rollers 115 are rotatably mounted to
second brackets 119.
Reference will now be made to Figure 6a and 6b, which
show details of a clutch mechanism for the spindle 66 and friction
mounting mechanism for both spindles 64, 66. Each of the spindles 64, 66
includes a rotatably mounted spindle body 120, each of which is attached to
a respective gear 68, 70. However, only spindle 66 includes the clutch
mechanism.
The spindle body 120 of spindle 66 includes an internal
tubular bearing 122 mounted on a shaft 124. The shaft 124 has an enlarged
head 126. A helical coil spring 128 is mounted between the enlarged head
126 and a washer 130 abutting the end of the bearing 122. The coil spring 128
presses the spindle body 120 against the gear 70 mounted on the shaft 124.
The shaft 124 extends through a bearing hole 134 in the
swing arm 60, and washers 136 are provided on either side of the swing arm
60. The washers 136 are secured to, or integral with the shaft 124.
Within the spindle body 120, there is a lever 138 including a
projecting lever end or actuation portion 140. The lever 138 is pivotally
mounted at 142 and a spring 144 biases the lever radially outwards. Bearing
projections 146 extend radially out through openings in the tubular spindle
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body 120.
Accordingly, in use, as shown in Figure 6a, to mount a roll
150 for taking up a release sheet from a film, the lever end 140 is pressed
radially inwards, to bring the projections 146 radially inwards. This permits
the roll 150 to be slid onto the spindle 66. With the roll 150 in position,
the
lever 138 can be released. Then, the spring 144 acts to press the bearing
projections 146 against the inside of the roll 150 securely mounting the
sleeve. Torque can then be transmitted between the sleeve 150 and the
spindle body 120.
The arrangement of the spring 128 and related elements of
the spindle 66 acts as a clutch to limit torque transmission between the
tubular spindle body 120 and the shaft 124. In particular, the drive ratio
required between the two spindles 64, 66 will vary as the size of the rolls on
the two spindles varies. It is impossible to maintain a completely accurate
ratio at all times. Accordingly, the ratio between the drive and driven gears
68, 70 is such as to ensure that, at a minimum, the second spindle 66 is
driven at a slightly faster speed than required, for all effective sizes of
rolls
on the spindles 66 (the effective size being the diameter of the roll at any
instant including material wound on it). Then, any excess speed is,
effectively, dissipated by the clutch mechanism in the spindle 66. In use,
this
will maintain a constant torque tending to wind up the release sheet.
Reference will now be made to Figures 4, 5, 7, 8, 12 and 13 to
describe a preferred film configuration and method of using the apparatus
of the present invention.
Referring first to Figure 12, there is shown, schematically, a
cross-section of a film in accordance with the present invention. This
cross-section is shown transverse to the longitudinal direction of the
handrail. This film is indicated at 160 and comprises a first film layer 162
with a first adhesive layer 164 on the underside thereof. To protect the film
until this is applied and to enable the film to be wound up onto a sleeve
150, a release sheet 166 is provided in known manner.
On top of the first layer 162, printed matter is provide as
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indicated at 168. This printed matter can be text, logos, images, etc., and it
is
expected that it will often comprise a repeated pattern. Shown
schematically, this printed matter would have a negligible thickness, so as
not to significantly affect the thicknesses of other layers. This printed
matter
168 is printed directly onto the top of the first film layer 162.
Following application of printed matter 1.68, a second film
layer 170 with a respectiv<e scecond layer of adhesive 172 is applied to the
top
of the first sheet, so as to sandwich the printed matter 168 between the two
film layers 162, 170. This serves to protect the printed matter.
Each film layer 162, 170 is preferably a polyurethane film
having a thickness of 0.076 mm (3 mils). The film is preferably a high gloss,
clear flexible film, coated with a clear acrylic, pressure sensitive adhesive.
These films are provided with a release liner. 'Thus, once the top of the
first
film layer 162 has been printed, the second film layer 170 v~~ith its
associated
adhesive 172, after the release liner or sheet removed, is then applied to the
top of the first film layer 162 to form the combined film 160 shown in
Figure 8.
The width of the film as supplied is commonly several feet.
For the present purposes, it would bea cut to widths depending upon the
particular handrail application.
While it is expected that the first and second film layers 162,
170 would both be clear, for some applications, it may be desirable to colour
the second film layer 170. Thus, the second layer 170 could be a solid,
uniform colour to provide a suitable background to advertising material or
:?5 a manufacturer's logo, and this colour could be a colour associated with
the
particular product or manufacturer. Additionally, the first film layer 162, if
desired, could be provided with some tinting.
Another aspect of the invention is the use of a film simply
to protect a handrail for an escalator or' moving walkway. For this purpose,
0 the film 160 could have a single layer. For such an application, the second
film layer 170 and its adhesive 172 could be omitted. For completeness, it is
noted that, conceivably, in such applications, some printed material could
CA 02389130 2002-07-03
- 18-
still be provided on the top of the first film layer 162, but such printed
matter would not then be protected, and would likely by subject to excessive
wear, marking, etc. during passage through the handrail drive mechanism.
Reference will now be made to Figure 13, which shows an
alignment mechanism 180, which essentially comprises a five-member
pivoted parallelogram mechanism. The mechanism 180 comprises a pair of
side elements 182, pivotally attached to a pair of transverse elements 184. a
central element 186 extends longitudinally, parallel to the side elements 182,
and is pivoted to the transverse elements 184. Tension springs 188 may be
omitted. If the springs 188 are omitted, it is a simple matter to hold the
unit
by hand and provide the closing tension required to centre the mechanism
mounted between the central element 186 and ends of the transverse
elements 184. The tension springs 188 act to bias the side elements 182
together, tending to collapse the parallelogram formed by the elements 182,
184.
Mounted on the central element 186 is a light source 190,
here a laser. The laser 190 is mounted in a bracket 192 pivotally mounted to
the central element 186.
Pivot connections between elements 182,184 are formed by
pivot pins, one of such is indicated at 194. Each pivot pin 194, beneath the
respective side element 182 is provided with a cylindrical collar 196.
A description will now be given of the use of the
equipment of the present invention. Firstly, before a film is applied to a
handrail, the handrail must be properly prepared. Most handrails, after a
period of use, will acquire a film of dirt and grease, preventing proper
adherence of an adhesive film.
Accordingly, the handrail is first washed with a solvent,
preferably an EH-101 solvent blend to remove all dirt and grease. EH-101
solvent blend is composed of ethyl acetate, naphtha, toluene and benzene.
For this purpose, operators should wear rubber gloves and use appropriate
applicators.
The handrail is then inspected for gouges or defects that
CA 02389130 2002-07-03
- 19-
impede application. If deep gouges are present, the handrail may need to be
replaced before the film is applied.
Any deep stains or marks can be removed with a scrub pad
and EH 101 solvent blend.
The handrail is cleaned by first cleaning an exposed run of
the handrail, and both handrails of an escalator or moving walkway could
be cleaned simultaneously. Each run is then marked with a china marker.
The drive mechanism of the escalator is then used to jog the escalator and
its handrail, to the end of the marked and cleaned areas, to expose further
stretches of the handrails. This procedure is repeated, and until the entire
length of both handrails of an escalator are cleaned.
Once clean, the handrail is coated with a sealant, to reduce
slightly the adhesive bond between the film and the handrail. This ensures
that the applied film can be peeled off readily. An appropriate sealant is
applied as specified, generally as a thin film. The film of sealant is buffed
to
a smooth, shiny finish. Again, the handrails on two sides of an escalator can
be treated simultaneously. The handrails are marked with a china marker
to indicate areas that have been sealed, and then jogged forward using the
escalator drive mechanism; this is repeated until both handrails are treated
and sealed.
To provide a film for an escalator, two matched rolls of film
are provided, one for each handrail. The handrails have the film applied
separately. Theoretically, it may be possible to apply both films
simultaneously, but this is usually not practical. It has been found that
application of the film needs to be monitored carefully, and, on occasion,
adjustments and the like are required. To monitor two films
simultaneously would be difficult.
For an escalator, an operator is provided with two matched
rolls of film, one for each handrail; the handrail is indicated at 200 and its
balustrade at 198 in the drawings, while the rolls of film are indicated at
174.
First, the operator should confirm that the correct rolls 174 are present for
the particular site or escalator. The wind configuration of the rolls should
be
CA 02389130 2002-07-03
- 20-
checked. Commonly, most advertising material should be viewed from one
direction, and should be applied in the appropriate orientation, for each of
up and down escalators.
The apparatus 10 is then mounted to the balustrade 198,
shown in Figures 3 and 4, with just the support member 12 attached, i.e.
with the cross member and attached components removed. The apparatus
is preferably mounted at the top of the escalator for down escalator units
and at the bottom of the escalator for up escalator units. On installations
where obstacles prevent mounting at these locations, it is permissible to
10 attach the apparatus 10 away from the ends on a straight, sloped portion of
the handrail.
The vacuum cups 16 are pumped up, in known manner, to
securely mount them to the balustrade. With the support member I2
securely mounted, the rest of the apparatus or the applicator is mounted by
sliding the swivel joint 20 onto the first cross member 19, in accordance
with figure 3a or Figure 3b as required.
The swing arm is raised into the retracted position with the
locking mechanism 63. A roll of film 174 is then mounted on the first
spindle 64. This is mounted as shown in Figures 6a and 6b and as detailed
above.
The apparatus 10 is mounted on the balustrade 198 with the
trough-shaped pressing mechanism 90 in the open configuration (Figure
8b). The pressing mechanism 90 is then closed. With the pivot connections
18, 22 and the sliding swivel joint 20 loosened as required, the horizontal
and vertical position of the apparatus is adjusted. The rear roller 41 and
rollers 110-115 serve to ensure that the apparatus is accurately located
relative to the handrail. If required, the nut and bolt assembly 105, 105a is
adjusted. With the apparatus properly located, the pivot connections 18, 22
and the sliding swivel joint 20 can be locked. Final angular adjustment is
achieved using a bubble level.
Alignment and clearances should then be checked. The
alignment can be checked using the mechanism shown in Figure 15. For
CA 02389130 2002-07-03
- 21-
this purpose, the centre line of the release sheet 166 is measured and
marked with a ruler and pen, or the release sheet can be provided with a
preprinted centre line. First, side elements 182 of the alignment mechanism
180 are grasped and displaced sideways and the mechanism 180 fitted onto
the handrail 200. The side elements 182 are then released, so that the springs
188 cause the mechanism 180 to snugly abut the sides of the handrail 200.
This will automatically align the laser 190 with the centre of the handrail.
The angular position of the laser 190 can be adjusted if desired.
The position of the laser beam relative to the centre line
mark will indicate whether roll 174 is properly aligned. If necessary, the
roll
position can be adjusted, depressing spindle lever 140 to release the spindle
tension and sliding roll 174 until the mark and laser coincide. The laser
guide is then removed from the handrail.
The swing arm 60 is locked in place using locking
mechanism 63 and the pressing mechanism 90 is opened. The roller 46 is
placed in the retracted position as shown in Figure 2a by turning handle 56
to the forward direction. This causes the crank member 54 to point upwards
and the roller 46 to lift above the handrail. With roll 174 in place, the end
160a of the film is fed around the retracted roller 46 and pulled manually
through the open press mechanism 90 and directed along the length of the
handrail. The tail end of the film is wrapped around the sides of the
handrail, after peeling back a corresponding length of the release sheet 166.
The adhesion at this point allows for wrinkles and air pockets. The pressing
mechanism 90 is then closed and release sheet 166, peeled off the film 190, is
directed around and above the roll 174 and secured by tape to a take up roll
178. The roll 178 is mounted on the spindle 66. The crank is released from
the ratchet 58 and rotated 180° and the crank member 54 now points
downwards relative to the crankshaft and the roller 46 is pressed by the
spring into contact with the handrail 200 (Figure 2b). The swing arm 60 is
then unlocked so that the roll 174 abuts and tracks against roller 46. The
weight of the swing arm adds to the force applied to the film during
application.
CA 02389130 2003-02-11
Once the film 160 contacts the handrail 200, this can be
jogged a short distance, to establish the thread-up and confirm the centre
alignment. The edges of the film should be even and symmetrical on the
handrail shoulders. If not, the position of roll 174 can be adjusted.
The leading portion of the film 160 adjacent the end 160a is
then manually wrapped around the handrail 20, to i:he configuration
shown in Figures 7c, ensuring that no bubbles are formed or left under the
film. The pressing mechanism 90 is then closed, and the escalator jogged to
run a test strip of approximately five feet to ensure that no bubbles or
wrinkles are formed. The pressure applied by roll 46 can be adjusted by
turning a nut (not shown) below spring 48a on plunger 52. Roll pressure
within press mechanism 90 is adjusted by turning the bolt 105a which
varies the closing of the two halves of the pressing mechanism.
Once it has been established that the apparatus is properly
centered with. adequate .~.learances and that the film 160 is being applied
uniformly without wrinkles, bubbles, cafe., then the escalator can be operated
to run the film around the entire length of the handrail.
The operator watches for the end 160a of the film to come
back towards the apparatu s 1 (). End 160a, which was pressed down by hand,
passes underneath the roller 41 which helps ensure that the film was
adequately pressed onto the handrail. Once end 160a returns to the
mechanism, a portion of the film is allowed to overlap the end 160a by
approximately 30.5 cm (12 inches).
At this time, the swing arm 60 is raised, and pressure on the
:Z5 roller 46 is released by engaging the handle 56. The pressing mechanism 90
is opened. The film is cut. The threaded screw member 21 is loosened to
permit removal of the upper portion of the apparatus 10 from the support
member 12. The support member 12 with the vacuum cups 16 is then
removed separately.
An overlap splice is than prepared by pulling up 7.6 to 10.2
cm (3 to 4 inches) of the excess film. This is trimmed cleanly at a 90~ angle.
It
is then smoothed down by hand ensuring that no bubbles or wrinkles are
-22a-
present.
CA 02389130 2002-07-03
- 23-
It can be noted that this splice joint is such that the natural action of
rollers
and other drive elements contacting the handrail will tend to smooth down
the joint, rather than tending to lift up the end of the film.
It is recognized that where the film 160 bears advertising, it
would almost certainly be intended that a particular application only be left
on an escalator for a set period of time. Indeed, rates for advertising on
escalator handrails will almost certainly be determined on a time basis.
When a particular advertiser's time has ended and it is
desired to replace the film, then the existing film needs to be removed. To
do this, the escalator is stopped with the film splice exposed on one handrail
(it is expected that each handrail will need to be stripped separately). The
end of the film is peeled up, to reveal the end last applied to the handrail.
This end can then be peeled off itself. If the film peels cleanly, then the
escalator can be started and the strip removed continuously while standing
at the top or bottom of the escalator.
If the film 160 leaves any residue on the handrail 200, then
it is preferred to proceed more slowly and to strip the handrail 200
carefully,
to reduce the clean up time. In this case, it is preferred to leave the
escalator
turned off and from a lower angle, peel the film from the lip area to the top
face in small steps and clean adhesive off as one proceeds.
Any remaining adhesive left on the handrail should be
removed. To remove adhesive, EH 101 solvent blend, acetone, Oil Flo or
Liftoff or other suitable solvent should be used, and again in accordance
with manufacturers' instructions.
Even for a handrail that has had a film applied before, it
should then be washed and sealed as detailed above.
Reference will now be made to Figures 14, 15 and 16, which
show an apparatus, generally indicated at 210, for peeling or removing a
film from a handrail. Here, a balustrade 212 of a moving walkway or the
like is shown, by way of example, with a handrail indicated at 214, in cross-
section.
The apparatus 210 has a pair of suction cups 216, which can
CA 02389130 2002-07-03
- 24-
correspond to the suction cups 16 of the earlier embodiment. A support arm
218 is provided extending out from the suction cups 216, corresponding to
the support member 12. A longitudinal member 220 has a general L-shape
and is mounted to the support arm 218. The member 220 includes a
downwardly extending end portion 222, so as to have an overall L-shape.
Pivotally mounted to the downwardly extending portion
222 is a yoke 224. A pin 226 extends between side arms 228 of the yoke 224
and a drive drum or cylinder 230 is rotatably mounted on the shaft 226. A
first drive gear 232 is securely mounted to the shaft 226. A first clutch
plate
234 is attached to a pressure plate 236 which is mounted for sliding
movement on the shaft 226 and is provided with splines or the like to cause
it to rotate with the shaft 226. A second clutch plate 235 is secured to the
drive drum 230. A spring 38 is provided for pressing the two clutch plates
234, 236 together, and acting between one arm 228 and the pressure plate
236.
Consequently, in use, as the drive drum 230 is rotated, as
detailed below, it transfers drive through the two clutch plates 234, 236 to
the shaft 226. This in turn drives the first drive gear 232.
A swing arm 240 is freely, pivotally mounted on the shaft
226. An idler gear 242 is pivotally mounted to the middle of the swing arm
240. A further shaft 244 is pivotally mounted to the other end of the swing
arm 240.
A second drive gear 246 and an associated first spindle 247
are secured together and to the shaft 244.
To maintain necessary pressures, telescopic shafts with bias
springs are provided, as indicated at 248, 249. The shaft 248 is pivotally
connected to the longitudinally extending member 220 and to a side arm of
the yoke 224. The second telescopic shaft 249 is pivotally connected between
the longitudinally extending member 220 and the swing arm 240 to
maintain a take-up roll (detailed below) pressed against the handrail.
In use, the apparatus 210 would be mounted as shown in
Figure 14. It would be mounted with the drive roller 230 pressed against the
CA 02389130 2003-02-11
25-
top of the handrail 214, by suitable adjustment of the vacuum clamps 216
and the support arm 218. A take-up roll 250 is mounted on the spindle 247
in such a manner that tcyrque or drive is transmitted between them. The
handrail would then be driven in the direction of the arrow 252 causing the
drum 230 to rotate. The drive gears 232 and 246 are sized so that the surface
of the take-up roll 250 is moving at a greater speed than the handrail 214. It
can be noted that, as detailed below, film is continuously wound on the roll
2511, so that this surface or circumferential velocity will increase, for a
constant angular velocity. The clutch mechanism, formed by the clutch
plates 234, 235 is designed to compensate for this difference in speeds, as
for
the apparatus described above, and to maintain a constant torque on the
take-up roll 250.
As shown with a film 254 present on the handrail, a free
end 256 of the film is first manually detached from the handrail and wound
sufficiently around the roll 250 to be secured thereto.
Consequently, as the handrail 214 is driven in the direction
252, the mechanism of the apparatus 210 continuously removes the film 254
and winds it up on the roll 250. This is continued until the entire film has
been removed. At this time, the apparatus 210 can then be used to remove
the .film on the opposite side of the moving walkway or escalator, in known
manner. It will be appreciated that, for this purpose, the support arm 218 is
configured to enable the apparatus to be mounted to both sides of escalators
and moving handrails.
It has been found that; for a 12.7 cm (5 inch) wide film, the
peel strength or load required is 155 Newtons (35 pou.nds). This is a
substantial load, and in some cases, it may cause slipping of the handrail
drive mechanism, particularly where it has been set up with relatively low
tension levels. For these situations, it is envisaged that the drive drum 230
can be provided with a separate power source, e.g. an electric motor, to
ensure adequate driving of both the apparatus 210 and the handrail during
film removal. Alternatively, the drivr~ drum 230 can be omitted and a
separate drive connected directly to the spindle 248.
CA 02389130 2003-02-11
It is also envisaged that the apparatus 210 could be integral
with the apparatus 10. For this purpose, the support member 12 and the
support arm 218 could be integral with one another, arid an appropriate
number of .suction cups 1.6, 216 could be provided. For a combined
apparatus, two suction cups may be sufficient, or it may be desirable to
provide more than two.
Then, the longitudinally extending member 32 of the
apparatus 10 and the longitudinally extending member 220 of the peeling or
stripping apparatus 210 can be integral with one another, so as to provide an
integral device or apparatus. Such a combined apparatus would enable
simultaneous stripping or removal of one film and mounting of a new
film, replacing the older film. Clearly, this is only acceptable in cases
where
stripping of the film leaves the handrail sufficiently clean, without
undesirable traces of adhesive and the like.
In such a combined apparatus, it is believed that the
problem of accidental stalling of the handrail will be more acute, due to the
increased load required to both remove an existing film and lay down a new
film. For this purpose, it may be more desirable to provide some separate
drive, from an electric motor or the like, to drive the equipment.
Reference will now he made to Figures 17a-17d, which
show examples of perforation patterns far incorporatian in the film of the
present invention. It is proposed to provide the film with a relatively strong
adhE~sive, but as will be explained, it is believed that this could cause
problems and .for this reason perforations are provided. When the adhesive
:Z5 is functioning properly, this will ensure that the film remains in
position,
does not tend to become remaved and entangled with the drive
mechanism. Nonetheless, it must be recognized that, for a variety of
reascms, the edge or end of the film, or other portions, of the film could
become detached for one reason or another.
In this context, it is to be appreciated that the film presently
proposed for the present invention has significant strength, and indeed has
an 1110 Newton (250 pound i break strength across a 12.7 cm (5 inch) width.
CA 02389130 2003-02-11
- 27-
If an edge of the film becomes detached, it could become entangled with part
of the drive or guidance Rnechanism of the handrail. (:onceivably an end of
the film could become wrapped around a guide roller and it could
progressively remove the entire length of the film and cause it to wrap
around the roller; likely the mechanism would jam before the entire length
had been removed. In any event, this is highly undesirable and would
present a significant maintenance problem. In this context, it is noted that
the present invention is intended for operation by relatively low-skilled
personnel, or at least personnel that need no detailed knowledge of an
escalator or handrail drive mechanism. Such personnel would not have the
skills necessary to deal with a major entanglement of the film about part of
the drive or guidance mechanism.
Accordingly, with the intention of avoiding this problem, it
is proposed to weaken the film, by means of perforations. The intention is
that: if any edge does become free ~>o as to adhere to part of the drive
mechanism etc., the film should enable a small portion of the film to
become detached from the handrail, by the film separating at lines or
perforations. This should ensure that a small portion of the film becomes
detached and this should not interrupt operation of the handrail. If when
inspecting the film, or replacing the film, it is noted that one or more
portions of the film are missing and it is suspected that they have become
attached to hidden parts ref the drive mechanism, then this can be noted for
investigation for a qualified maintenance team at a later date.
As noted above, the peel strength for a 7 2.7 cm (5 inch)
width of film is approximately 155 Newtons (05 pounds). It is intended to
provide perforations to weaken the film strength down to approximately
200 Newtons (45 pounds). 'Chis gives an adequate margin for enabling the
film to be peeled off the handrail, while at the same tune significantly
weakening the film, down from the original strength of 1110 Newtons (250
:~0 pounds). This avoids any excessive and unwanted loads being applied to
any part of the drive and guidance mechanism.
Reference twill now be made to Figures 17a, 17b which show
CA 02389130 2003-02-11
2$_.
in detail alternative perforation patterns. It will be appreciated that any
suitable perforation configuration can be provided. Indeed, it is conceivable
that the arrangement c.~f the perforations could be shaped according to
advertising material placed on the film and even incorporated as part of the
advertising material; otherwise the perforations are intended to be largely
invisible to an ordinary user.
In all of Figures 17a-17d, a simple section of handrail is
indicated, with the longitudinal axis of the handrail extending vertically in
all these figures. It will be appreciated that the perforation pattern will be
repeated at suitable intervals, for example, every 30.5 cm (12 inches}.
Referring first to Figure 17a, a film is indicated at 260 and is
provided with a diagonal lire of perforations 262. Additionally, Figure 17a
shows side margins 2611. These were originally intended to provide
unperforated zones at the edge of the film, in the belief that this was
necessary to maintain sufficient film strength. In fact, it has been found
that
the opposite is the case; it is necessary to have significant perforations
going
the full width in order to reduce the film's strength down to a suitable
level.
For this reason, it is envisaged that unperforated side margins will likely
not be provided.
The length of the slits and the gap between the slits can be
varied and the following table gives some exemplary dimensions:
Slit Length (mm/inches) Slit Gap (mm/inches}
1.3/0.05 5.1/0.2
1.3 / 0.05 10.2 J 0.4
1.310.()5 20.3 j0.8
0.6/0.025 20.3/0.8
Figure 17b shows a slight variation of Figure 17a. Here, the
slits are longitudinal, although the line alcmg which the slits or
perforations
CA 02389130 2003-02-11
are located is again diagonal 45 degrees. The slits here are 5.1 mm (0.2
inches) long and spaced apart by 5.1 mm. (0.2 inches).
A further variant is shown in Figure 17c. Here, a line of
perforations is provided, which comprises different line segments all
running at 45 degrees to the longitudinal axis for the handrail, but in
alternating directions. Slit lengths and slit gaps as in the table above could
be employed in this confil;uration.
Figure 17c. also shows another variant that: can be employed
with all the configurations for the perforations, namely the provision of
two rows of longitudinally extending perforations 270 defining side
margins. Here the side margins are relatively small at 1.6 mm (0.0625
inches), but the side margins could h ave varying dimensions and could be
significantly larger, for example 6.~~5 mm (0.25 inches) or larger. More
particularly, the side margins could be dimensioned so that a portion of the
film that, in use covers just the top surfaces of the handrail is separated by
these longitudinally extending perforations 270 from film that wraps
underneath the bottom of the lips of the handrail.
Figure 17d, finally, shows a simple version of the
perforations. Here, the perforations are arranged in a straight line 272
extending perpendicularly across the Film. Again, slit lengths and slit gaps
can be taken from the table given above. Longitudinally extending
perforations 270 can optionally be included.
It is noted above that: the film is ideally made from two
layers of polyurethane with a thickness of 0.076 mm (3 mils). It is now
anticipated that the bottom layer of film could have a thickness of 0.053 mm
(2 mil) and the top layer a thickness of 0.076 rnm (3 mil) and conceivably,
both layers could have a thickness of 0.053 mm (2 mil). This will reduce the
overall break strength of the film, and hence reduce the level of perforation
required to reduce the break strength down to a reasonable figure, for safety
10 purposes.
A further aspect of the present invention is to provide a
flexible film for mounting on a handrail, to provide a cleaning function.
CA 02389130 2003-02-11
-29a~~
Thus, rather than providing advertising or the like, it is envisaged that the
CA 02389130 2002-07-03
- 30-
surface of the film could be provided with some coating to provide a
cleaning function as it runs through the hidden and enclosed mechanism
of an escalator or moving walkway. For this purpose, it will be appreciated
that it is not necessary for the film to have two layers. With reference to
the
configuration of Figure 12, the layers 168 and 170, and optionally 172, could
be omitted, i..e. at a minimum for this aspect of the invention, just a layer
162 (with different properties from those described above, as detailed below),
an adhesive layer 164 and a release sheet 166 are required.
For example, in one embodiment, such a proposal could
include an adhesive on the top surface of the film, i.e. similar to the layer
172 but with selected adhesive properties, intended to pick up fluff, dirt,
lint
and the like from within the escalator mechanism. For this purpose, the
film would be mounted on the handrail as described above and the
handrail operated for a desired period of time. The film would then be
removed, taking with it any fluff, dirt, etc. picked upon the film. Other
variants are envisaged. For example, the film could be provided with a
porous or absorbent structure to absorb oils, greases and the like from
surfaces within the handrail mechanism; this could be provided either by
incorporating this characteristic into the single layer 162 or by providing a
separate layer adhered to the film 162 by the adhesive layer 172. It is
recognized that an inherent difficulty with such an approach is that the
drive mechanism of many escalators imposes a strong pinch load on the
handrail, which will naturally tend to squeeze out absorbed oils, greases and
other fluids. For example, many escalators now employ a so-called linear
drive which, by its very nature, requires a high pinch load, to provide an
adequate drive.
For such installations, it is envisaged that an absorbent
layer could be in the form of an open, porous absorbent material provided
with longitudinally extending ribs or the like of relatively hard material.
These ribs would be flush with the absorbent material, but would serve to
transfer the pinch load of the rollers, to prevent excessive compression of
the porous material, thereby preventing absorbed fluids and the like from
CA 02389130 2002-07-03
31-
being expelled.
A further possibility is that a mufti-layer film could be
provided. For example, a bottom or main film could be provided with
adhesive on both sides, so as to adhere to an escalator handrail on one side.
The adhesive on the other side could initially be bonded to an absorbent
layer of material. Such a film would first be run so that the absorbent layer
picks up oils, other fluids, etc. After a sufficient period of time, this
absorbent layer would, separately, be removed, to leave the film itself and
an exposed layer of adhesive. The film itself would then be run through the
drive mechanism, so that the exposed layer of adhesive picks up dirt, fluff
and the like. The film would then be peeled off the escalator to remove the
accumulated dirt, fluff, etc.
The presently preferred adhesive film only sticks properly
to Hypalon rubber handrails. Hypalon is a chlorosulphonated rubber made
by DuPont, which has enhanced UV properties and is pigmentable. It is
more expensive material, but is commonly selected where coloured
handrails are required.
Most handrails are made with SBR (styrene butadiene
rubber) because it has sufficient properties for most applications and is
cheaper. SBR can only be black. Adhesive film will initially stick, but will
delaminate within days, if not hours because of the antioxidant component
that leaches from SBR.
Hence, for the presently preferred adhesive, most escalator
sites will require handrail replacement/upgrade to Hypalon prior to film
application. It may be possible to find a suitable adhesive that will bond
adequately to SBR handrails.
It will be appreciated that while preferred embodiments of
the invention have been described, numerous variations are possible
within the scope of the invention as defined in the following claims.
In particular, the degree to which the film 160 wraps
around the handrail can be adjusted and will depend on individual
handrail profiles and installations. Having the film wrap a large way
CA 02389130 2002-07-03
- 32-
around the handrail Iips is advantageous as it puts the edge of the film well
away from users and not readily accessible to anyone who, for whatever
reason, might want to try and peel it off. On the other hand, where the film
wraps all the way around the lips, it can tend to buckle as the handrail
travels around end rollers and the like. Accordingly, it is expected that some
compromise will usually be needed between these two parameters.
On a more general note, the film described herein can be
applied to a stationary handrail as used in a normal stairwell.
