Technical field
[0001] The present invention relates to a rolling platform ladder according to the preamble
of the first claim.
Background art
[0002] A rolling platform ladder is for example known from
US 2008/0093166 A1. This known rolling platform ladder comprises a platform ladder part and an undercarriage
part. The undercarriage part comprises a set of wheels for engaging with the ground
during rolling of the rolling platform ladder. The platform ladder part has legs for
engaging with the ground when the ladder is to be climbed upon. The platform ladder
part is raisable from the ground to lift the legs from the ground so that the platform
ladder can be rolled. To this end, a lifting mechanism is provided, by means of which
a user can lift the platform ladder part from a lowered condition, in which the legs
of the platform ladder part are engaging with the ground, to a raised condition, in
which the legs of the platform ladder part are raised from the ground and the rolling
platform ladder is supported on the wheels of the undercarriage part. The lifting
mechanism comprises a pair of lever arms by means of which a user can operate the
lifting mechanism.
Disclosure of the invention
[0003] It is an aim of the present invention to provide a rolling platform ladder which
is more user-friendly to operate.
[0004] This aim is achieved according to the invention with the rolling platform ladder
showing the technical characteristics of the first independent claim.
[0005] According to the invention, the lifting mechanism has a lever arm which is provided
such that the ladder part is raisable onto the undercarriage party by manual force.
Furthermore, in raised condition a grip of the lever arm is positioned against an
elevated part of the platform ladder part, the elevated part preferably being a predetermined
height above the ground, such that in raised condition the grip of the lever arm and
the elevated part of the platform ladder part are grippable together with one hand
for moving the rolling platform ladder by rolling. Still further, upon release of
the lever arm the platform ladder part is lowered by gravity to the lowered condition.
[0006] As a result of these characteristics, a user can raise the platform ladder part for
rolling it by a single movement, which comprises gripping the lever arm at the grip
and pulling the grip against the elevated part of the platform ladder part. Subsequently,
by simply holding the grip against the elevated part with the same hand, the user
can move the rolling platform ladder around by rolling it on the wheels of the undercarriage
part, on which the rolling platform ladder is supported in the raised condition. Subsequently,
upon release of the lever arm, the platform ladder part is lowered onto its legs by
gravity, so that before the user climbs onto the ladder its position on the ground
is secured.
[0007] So as a result of these characteristics, a more user-friendly rolling platform ladder
can be achieved, which is quickly and easily raised to the raised condition for being
moved and safely returned to the lowered condition upon release of the lever arm.
[0008] In an embodiment of the rolling platform ladder according to the present invention,
the platform ladder part comprises a raised platform which is in lowered condition
at a height of 20 cm to 100 cm above the ground.
[0009] The raised platform has the advantage that it provides the user of the rolling platform
ladder with a platform on which the user can stand. Furthermore, the raised platform
can also be advantageously used for storing objects, such as for example grocery goods,
thereon. In this way, the objects stored on the raised platform, can be carried around
on the rolling platform ladder when the rolling platform ladder is being moved around
by the user. The raised platform having a height ranging from 20 cm to 100 cm above
the ground in the lowered condition of the rolling platform ladder, is advantageous
for the use of the rolling platform ladder for filling the shelves in a store, such
as for example a supermarket or a grocery store. The raised platform being positioned
at such height makes it easy for the user standing on the raised platform to reach
to the upper shelves for filling those upper shelves with for example grocery goods.
[0010] In an embodiment of the rolling platform ladder according to the present invention,
a front side of the platform ladder part comprises a ladder part with steps for climbing
the platform ladder part and wherein the lever arm is positioned at a lateral side
of the front side.
[0011] The ladder part with the steps provides a beneficial means for the user of the rolling
platform ladder to move on or off the platform ladder part. The lever arm being positioned
on the lateral side of the front side of the platform ladder part has the advantage
that the lever arm is easy to reach by the user standing in front of the rolling platform
ladder, and has the advantage that the lever arm does not hinder the user in moving
on or off the platform ladder part.
[0012] In an embodiment of the rolling platform ladder according to the present invention,
the platform ladder part comprises a safety rail construction, positioned for surrounding
a user present on the platform ladder part, and wherein the elevated part is part
of the safety rail construction.
[0013] The safety rail construction is beneficial for the safety of a user standing on the
platform ladder part. The safety rail construction prevents the user from accidentally
falling off the platform ladder part. The safety rail also has the advantage of providing
a support for the user on which the user can lean, for example when reaching to shelves
for filling those shelves. Providing the elevated part, against which the grip of
the lever arm is positioned in the raised condition of the platform ladder part, as
a part of the safety rail construction has the advantage that the construction of
the rolling platform ladder is simplified since no additional means need to be provided
to form the elevated part.
[0014] In an embodiment of the rolling platform ladder according to the present invention,
the lifting mechanism comprises a plurality of pivot arms which are pivotably mounted
to, on the one hand, the undercarriage part and, on the other hand, the platform ladder
part, in such a way that the platform ladder part and the undercarriage part are movable
with respect to each other in height direction of the rolling platform ladder, and
wherein the lever arm is an extension of one of the pivot arms.
[0015] The inventors have found that the use of the pivot arms allows a simple construction
of the lifting mechanism of the rolling platform ladder, which is easy to assemble
and to maintain. The lever arm extending from one of the pivot arms has the advantage
that the pivot arms are operated directly by the lever arm, and has the advantage
that limited means are required for operating the lifting mechanism by means of the
lever arm.
[0016] In an embodiment of the rolling platform ladder according to the present invention,
the lever arm has an S-shape.
[0017] The inventors have found that the S-shape of the lever arm is an advantageous shape
for positioning the grip of the lever arm near the front side of the ladder platform,
where the grip of the lever arm is easily reachable by a user of the rolling platform
ladder.
Brief description of the drawings
[0018] The invention will be further elucidated by means of the following description and
the appended figures.
Figure 1 shows a perspective view of the rolling platform ladder according to an embodiment
of the present invention.
Figure 2 shows a side view of the rolling platform ladder of Figure 1 in the lowered
condition.
Figure 3 shows a side view of the rolling platform ladder of Figure 1 in the raised
condition.
Figure 4 shows a separate view of the lever arm of the rolling platform of Figure
1.
Modes for carrying out the invention
[0019] The present invention will be described with respect to particular embodiments and
with reference to certain drawings but the invention is not limited thereto but only
by the claims. The drawings described are only schematic and are non-limiting. In
the drawings, the size of some of the elements may be exaggerated and not drawn on
scale for illustrative purposes. The dimensions and the relative dimensions do not
necessarily correspond to actual reductions to practice of the invention.
[0020] Furthermore, the terms first, second, third and the like in the description and in
the claims, are used for distinguishing between similar elements and not necessarily
for describing a sequential or chronological order. The terms are interchangeable
under appropriate circumstances and the embodiments of the invention can operate in
other sequences than described or illustrated herein.
[0021] Moreover, the terms top, bottom, over, under and the like in the description and
the claims are used for descriptive purposes and not necessarily for describing relative
positions. The terms so used are interchangeable under appropriate circumstances and
the embodiments of the invention described herein can operate in other orientations
than described or illustrated herein.
[0022] Furthermore, the various embodiments, although referred to as "preferred" are to
be construed as exemplary manners in which the invention may be implemented rather
than as limiting the scope of the invention.
[0023] The term "comprising", used in the claims, should not be interpreted as being restricted
to the elements or steps listed thereafter; it does not exclude other elements or
steps. It needs to be interpreted as specifying the presence of the stated features,
integers, steps or components as referred to, but does not preclude the presence or
addition of one or more other features, integers, steps or components, or groups thereof.
Thus, the scope of the expression "a device comprising A and B" should not be limited
to devices consisting only of components A and B, rather with respect to the present
invention, the only enumerated components of the device are A and B, and further the
claim should be interpreted as including equivalents of those components.
[0024] Figure 1 shows a perspective view of the rolling platform ladder 1 according to an
embodiment of the present invention. The rolling platform ladder 1 comprises an undercarriage
part 8 and a platform ladder part 2, which are movably fixed to each other by means
of pivot arms 12. The pivot arms 12 are part of a lifting mechanism of the rolling
platform ladder 1, which lifting mechanism is provided for moving the platform ladder
part 2 between a lowered condition wherein the platform ladder part 2 supports on
the ground, and a raised condition wherein the platform ladder part 2 is raised from
the ground. The lifting mechanism is operated by means of a lever arm 10, shown in
more detail in Figure 4, which extends from one of the pivot arms 12. The lever arm
10 is preferably arranged such that the lever arm 10 is easy to reach by a user of
the rolling platform ladder 1 for operating the lifting mechanism. In this embodiment,
this is achieved, among other things, by the S-shape of the lever arm 10. Because
of the S-shape the grip 11 on the lever arm 10 is positioned near the front side of
the rolling platform ladder 1, at which position the grip 11, and thereby the lever
arm 10, is easily reachable by a user of the rolling platform ladder 1. Another advantage
of this S-shape is that the lower end of the lever arm 10 and the respective pivot
arm 12 which is an extension of the lever arm 10 are in the lowered condition of Fig.
2 in a suitable, relatively sharp angle with respect to horizontal, which facilitates
the raising of the platform ladder part 2 to the raised condition. Then, in the raised
condition, shown in Fig. 3, the lower end of the lever arm 10 and the respective pivot
arm 12 are still in a sharp angle with respect to horizontal, which can ensure that
the platform ladder part 2 drops to the lowered condition due to gravity as soon as
the lever arm 10 is released.
[0025] In the embodiment shown in figures 2 and 3, the angle is respectively around 45°
in the raised condition and around 60° in the lowered condition. In alternative embodiments,
however, the angle may vary, for example between 30° and 60° in the raised condition
and between 50° and 80° in the lowered condition.
[0026] In the embodiment shown in the figures, the lever arm 10 is an extension of one of
the pivot arms 12 near the front side of the rolling platform ladder. In alternative
embodiments, the lever arm 10 could however also be attached to a pivot arm 12 near
the back side of the rolling platform ladder, or to a pivot arm in any position between
the front and back sides.
[0027] The platform ladder part 2 comprises legs 3, which are provided for engaging with
the ground when the platform ladder part 2 is supported on the ground in the lowered
condition. In between the legs 3 at the front side of the platform ladder part 2,
steps 4 are arranged, which form the ladder part of the platform ladder part 2. The
ladder part is provided for climbing on and off the platform ladder part, and facilitates
a user of the rolling platform ladder 1 in moving between the ground and a raised
platform 6 of the platform ladder part 2. The raised platform 6 is provided for a
user to stand on, for example while filling the shelves in a store with goods. These
goods can be stored on the raised platform 6 or one ore more shelves 7 provided on
the platform ladder part 2. The platform ladder part 2 further comprises a safety
rail construction 5 for surrounding a user present on the platform ladder part 2.
In this embodiment, the safety rail construction 5 comprises a number of rods arranged
around the raised platform 6, together with some side walls attached onto the raised
platform 6, which side walls prevent the feet of the user from sliding of the raised
platform 6. At the top and front side of the platform ladder part 2, the safety rail
construction 5 is further provided with a tiltable closing element, which can be lifted
up to allow the user to step on and off the raised platform 6, and put back such that
the safety rail construction 5 is closed off to surround the user again.
[0028] The undercarriage part 8 comprises a set of wheels 9, which are provided for rolling
the rolling platform ladder 1 around on the ground, such that the user can move the
rolling platform ladder 1 between different positions. In the lowered condition of
the platform ladder part 2, the rolling platform ladder 1 is prevented from being
rolled around because of the grip of the legs 3 of the platform ladder part 2 engaging
on the ground. This allows the user to safely get on and off the platform ladder part
2, and to work safely from the rolling platform ladder while standing on the platform
ladder part 2, without a risk of the rolling platform ladder suddenly 1 rolling away.
In the raised condition, however, the legs 3 are lifted up from the ground and the
rolling platform ladder 1 can be rolled around freely on the ground. This allows the
user to walk around with the rolling platform ladder 1.
[0029] Figures 2 and 3 show a side view of the rolling platform ladder 1 of Figure 1 respectively
in the lowered condition of the platform ladder part 2 and the raised condition of
the platform ladder part 2. These figures show how the lever arm 10 is used for operating
the lifting mechanism of the rolling platform ladder 1. To move the platform ladder
part 2 from the lowered condition to the raised condition, a user grabs the grip 11
of the lever arm 10 and pulls the grip 11 against an elevated part of the platform
ladder part 2. In this embodiment, the elevated part is a part of the safety rail
construction 5. As a result of this movement, the lever arm 10 pulls on the pivot
arm 12 from which the lever arm 10 is extending, in such a way that the platform ladder
part 2 is raised with respect to the undercarriage part 8 and the ground, thereby
disengaging the legs 3 of the platform ladder part 2 from the ground. Because of the
use of the lever arm 10, this operation requires limited force from the user, and
the user can easily hold the platform ladder part 2 in the raised condition by grabbing
with one hand around the grip 11 of the lever arm 10 and the elevated part of the
platform ladder part 2. This has the advantage that one hand of the user remains free
for other uses. To move the platform ladder part 2 back to the lowered condition,
the lever arm 10 is released and the platform ladder part 2 is lowered back to the
ground by gravity.
List of references:
[0030]
- 1
- rolling platform ladder
- 2
- platform ladder part
- 3
- leg
- 4
- step
- 5
- safety rail construction
- 6
- raised platform
- 7
- shelf
- 8
- undercarriage part
- 9
- wheel
- 10
- lever arm
- 11
- grip
- 12
- pivot arm
1. A rolling platform ladder (1) comprising a platform ladder part (2) and an undercarriage
part (8), the undercarriage part (8) comprising a set of wheels (9) for engaging with
the ground during rolling of the rolling platform ladder (1), the platform ladder
part (2) having legs (3) for engaging with the ground when the rolling platform ladder
(1) is to be climbed upon, the platform ladder part (2) and the undercarriage part
(8) being movably fixed to each other in such a way that the platform ladder part
(2) is raisable from the ground to thereby lift the legs (3) from the ground and enable
rolling of the rolling platform ladder (1) on the wheels (9) of the undercarriage
part (8), the rolling platform ladder (1) further comprising a lifting mechanism with
a lever arm (10), provided such a user can lift the platform ladder part (2) from
a lowered condition, in which the legs (3) of the platform ladder part (2) are engaging
with the ground, to a raised condition, in which the legs (3) of the platform ladder
part (2) are raised from the ground and the rolling platform ladder (1) is supported
on the wheels (9) of the undercarriage part (8), characterised in that the lever arm (10) of the lifting mechanism is provided such that the ladder part
is raisable onto the undercarriage by manual force, in that in raised condition a grip (11) of the lever arm (10) is positioned against an elevated
part of the platform ladder part (2), the elevated part being a predetermined height
above the ground, such that in raised condition the grip (11) of the lever arm (10)
and the elevated part of the platform ladder part (2) are grippable with one hand
for moving the rolling platform ladder (1) by rolling, and in that upon release of the lever arm (10) the platform ladder part (2) is lowered by gravity
to the lowered condition.
2. The rolling platform ladder (1) according to claim 1, wherein the platform ladder
part (2) comprises a raised platform (6) which is in lowered condition at a height
of 20 cm to 100 cm above the ground.
3. The rolling platform ladder (1) according to any one of the preceding claims, wherein
a front side of the platform ladder part (2) comprises a ladder part with steps (4)
for climbing the platform ladder part (2) and wherein the lever arm (10) is positioned
at a lateral side of the front side.
4. The rolling platform ladder (1) according to any one of the preceding claims, wherein
the platform ladder part (2) comprises a safety rail construction (5), positioned
for surrounding a user present on the platform ladder part (2), and wherein the elevated
part is part of the safety rail construction (5).
5. The rolling platform ladder (1) according to any one of the preceding claims, wherein
the lifting mechanism comprises a plurality of pivot arms (12) which are pivotably
mounted to, on the one hand, the undercarriage part (8) and, on the other hand, the
platform ladder part (2), in such a way that the platform ladder part (2) and the
undercarriage part (8) are movable with respect to each other in height direction
of the rolling platform ladder (1), and wherein the lever arm (10) is an extension
of one of the pivot arms (12).
6. The rolling platform ladder (1) according to any one of the preceding claims, wherein
the lever arm (10) has an S-shape.