Patent Description:
A challenge with traditional elevators is that the provided elevator car is usually optimized for transporting persons. However, in certain situations, such as during the construction of the building, for instance, there also exists a need to transport heavy cargo to upper parts of the building.

Some buildings are provided with separate elevator cars for transporting persons and separate for transporting cargo. However, for practical reasons this is not the case in all buildings. Previously known elevators are disclosed in <CIT>, <CIT>, <CIT> and <CIT>, for instance.

Consequently, in some installations, the same elevator car which is used for transporting persons also needs to be used for transporting cargo. When such a need arises, a common problem is how to be able to get the heavy cargo into the elevator car and out of the elevator car without damaging the elevator car in such a way that it no longer looks tidy and nice for transport of persons.

An object of the present invention is to solve the above-mentioned drawback and to provide an elevator system which is well suited for use both to transport persons and cargo. This object is achieved with the elevator system according to independent claim <NUM> and the method according to independent claim <NUM>.

Use of an elevator car where the floor is provided with at least a first and a second rotatably suspended roll providing a rolling floor surface, and with a floor section consisting of one or more floor elements which are movable between a load bearing position, where they are aligned on top of the rolling floor surface, and a transport position, where the rolling floor surface is revealed, makes the elevator car excellent to use both for persons and cargo.

In the following the present invention will be described in closer detail by way of example and with reference to the attached drawings, in which.

<FIG> illustrates a simplified side view of an elevator system <NUM> with an elevator car <NUM> which is arranged to move vertically in a hoistway <NUM> between landings <NUM> of a building <NUM>. The elevator car is moved by a hoisting machinery <NUM> which is controlled by an elevator control <NUM>. The hoisting machinery <NUM> utilizes a rope <NUM> to move the elevator car <NUM> and a counterweight <NUM> in the hoistway <NUM>. For simplicity, all details and elements participating in moving the elevator car are not illustrated in <FIG>. One alternative is to utilize a similar solution as illustrated in <FIG>.

The floor <NUM> of the elevator car <NUM> is provided with at least a first and a second roll <NUM>, which are rotatably suspended in the elevator car <NUM> for rotation around rotation axles <NUM>. The ensure easy loading and unloading, the rotation axles <NUM> are in the illustrated example parallel to a door opening <NUM> of the elevator car <NUM>, due to which a heavy object may be directly pushed into the elevator car from the door opening <NUM> onto the rolls <NUM>.

In the illustrated example it is by way of example assumed that the number of rolls <NUM> is larger than two, so that a major part of the bottom area of the elevator car is provided with rolls <NUM>. The rolls may be rotatably suspended from the bottom part of the elevator car or alternatively from the side walls <NUM> of the elevator car. Irrespectively of the number of rolls <NUM>, the uppermost parts of the rolls that at each moment are located uppermost together provide a rolling surface <NUM> at a plane illustrated by dotted line <NUM>. This rolling surface <NUM> carries in the cargo transport position heavy objects that are pushed into or out of the elevator car <NUM> on the rolls.

An advantage with the rolling surface <NUM> provided by the rolls <NUM> is that when loading or unloading cargo into the elevator car <NUM>, the cargo can slide along the rolling surface due to the rotation of the rolls <NUM>. This significantly simplifies loading and unloading of heavy cargo.

As transportation of persons requires a steady base for the persons to stand on, the elevator car <NUM> is provided with a floor section comprising one or more floor elements <NUM>, which are movable between a load bearing position, where the one or more floor elements are aligned on top of the rolling floor surface <NUM> and provide a fixed floor surface, and a transport position, where the rolling floor surface <NUM> is revealed.

<FIG> illustrates the one or more floor elements <NUM> in the transport position, where the elevator car is optimized for transport of cargo, and <FIG> illustrates the one or more floor elements <NUM> in the load bearing position, where the one or more floor elements <NUM> are aligned on top of the rolling floor surface <NUM> and provide a fixed floor surface for carrying the weight of person standing on it.

In the illustrated example it is by way of example assumed that the elevator car <NUM> is provided with two floor elements <NUM>, which are movable between the load bearing position and the transport position by rotation around pivot points <NUM>. In that case each of the floor elements <NUM> is separately attached by pivot points to the elevator car, preferably proximate to the opposite side walls of the elevator car. Proximity to the side walls <NUM> is advantageous, as in that case the area of the rolling surface <NUM> becomes as large as possible in the transport position. The pivot points <NUM> make it possible to lift each floor element <NUM> from the horizontal load bearing position illustrated in <FIG> to an upright vertical transport position illustrated in <FIG>. In that case each floor element is located along a side wall <NUM> of the elevator car in an upright position, due to which the rolling surface <NUM> is revealed between the two floor elements. Naturally a similar solution may be utilized also in case only one floor element is in use. However, in that case this single floor element will extend to a larger height along the side wall <NUM> of the elevator car <NUM>, which makes the elevator floor element heavier and more clumsy to move between the transport and load bearing positions. The pivot points <NUM> may be implemented by means of hinges, for instance.

Alternatively, or in addition to using hinges as the pivot points <NUM> which facilitate moving the floor elements manually between the load bearing position and the transport position, the elevator car may be provided with a drive unit <NUM> (or drive units) such as an electric motor, a hydraulic motor or hydraulic cylinder, or a pneumatic motor or pneumatic cylinder which can be used to move the one or more floor elements <NUM> between the load bearing position and the transport position. In that case a control panel of the elevator car <NUM>, for instance, may be used to control the movement of the one or more floor elements <NUM> by utilizing electric power, hydraulic power or pneumatic power.

Still another alternative for moving the one or more floor elements <NUM> into the transport position is to completely remove the elements from the elevator car <NUM> to an elevator landing <NUM>. In that case no pivot points are needed, but instead the elevator car may be provided with attachment points for attaching the one or more floor elements in position with screws (if needed), for instance, when the one or more floor elements <NUM> are in the load bearing position.

In the example illustrated in <FIG>, the elevator car <NUM> is provided with a sensor <NUM> providing the elevator control <NUM> with an indication about the position of the one or more floor elements <NUM>. In this way the elevator control obtains information when the one or more floor elements <NUM> are in the transport position and when they are in the load bearing position. This information is useful, because it may be advantageous to stop the elevator car at different heights in the hoistway <NUM> in relation to the landings <NUM> depending on the position of the one or more floor elements <NUM>.

From <FIG> it can be seen, that when the one or more floor elements <NUM> are in the transport position, the elevator control <NUM> has stopped the elevator car at a height in the hoistway <NUM> where the rolling surface <NUM> is located a distance D above the upper surface of the landing <NUM>. This is advantageous, as a load transported to the elevator car on a trolley having wheels, may be easily transferred directly from the trolley onto the rolling surface. Depending on the implementation, in the transport position, the elevator car <NUM> is preferably stopped at a height where the rolling floor surface <NUM> is at the same height or above the upper surface of the landing <NUM>.

Correspondingly, it can be seen from <FIG> that when the one or more floor elements <NUM> are in the passenger load bearing position, in other words ready to receive passengers, the elevator control <NUM> has stopped the elevator car <NUM> in the hoistway <NUM> at a height where an upper surface of the one or more floor elements <NUM> is at the same height as the upper surface of the landing <NUM>.

Consequently, when taking into account also the thickness of the one or more floor elements <NUM> laying on top of the rolling floor surface <NUM> in <FIG>, it is clear that the elevator control <NUM> is configured to stop the elevator car <NUM> at a higher position in relation to the landing <NUM> when the one or more floor elements <NUM> are in the transport position, than when the one or more floor elements <NUM> are in the load bearing position.

As the need for transporting heavy objects is typically at its maximum when a building is being constructed, a construction time modification of the elevator car illustrated in <FIG> may be utilized only during the construction time of the building. Consequently, for the construction time of the building the elevator car <NUM> may be set in a hybrid mode, where the rolling floor surface <NUM> and the one or more floor elements <NUM> have been provided to the floor <NUM> of the elevator car. Atthat stage, the elevator car is well suited for both transport of cargo and passengers, depending on if the one or more floor elements <NUM> are in the passenger load bearing position illustrated in <FIG> or in the transport position illustrated in <FIG>. However, once the construction time modification is no longer needed as the building is completed, this hybrid mode may no longer be needed. At that stage the elevator car may be set in a person transport mode, by removing the rolls providing the rolling floor surface <NUM> and the floor elements <NUM>. Consequently, the floor <NUM> of the elevator car may be revealed and possibly provided with a new coating for more permanent transport of passengers. At that stage the elevator control <NUM> may, if necessary, be set into a new mode ensuring that the upper surface of the floor <NUM> is at the same level as the upper surface of the landings <NUM> in the hoistway, when the elevator car <NUM> stops at a landing.

<FIG> illustrate a second embodiment of an elevator car <NUM>'. The second embodiment is very similar as the one explained in connection with <FIG>. Therefore, in the following, the embodiment of <FIG> will mainly be explained by pointing out the differences.

In <FIG> the elevator car is set into a hybrid mode, for the construction time of the building, for instance, due to which it is provided with rolls <NUM> providing a rolling surface <NUM> and one or more floor elements <NUM>, which can be moved between the cargo transport position (illustrated in <FIG>) and the passenger load bearing position, as has been illustrated and explained in connection with <FIG>.

However, in <FIG> it is by way of example assumed that the construction of the building has ended (for instance), such that the construction time modification with the hybrid mode is no longer needed. Consequently, the elevator car <NUM>' has been set in a person transport mode by removing the rolling floor surface <NUM> and the one or more floor elements <NUM> from the elevator car <NUM>' to reveal the floor <NUM> of the elevator car <NUM>'. Possibly, a new surface coating has been provided to the floor <NUM> to make it suitable and tidy for passenger transport.

In the embodiment of <FIG>, the elevator car has additionally been provided with a height adjustable roof construction to obtain an increased interior height well suited for loading of long or high objects <NUM>' into an elevator car <NUM>'.

As can be seen in <FIG>, objects <NUM>' which are higher than the height of the door opening <NUM>' in the elevator car <NUM>' can easily be loaded onto the rolling floor surface by tilting at the door, and subsequently turning into an upright position. After this the objects <NUM>' can slide deeper into the elevator car <NUM>' on the rolling surface.

When comparing <FIG> illustrating the same elevator car <NUM>', one can observe that in <FIG> the interior height of the elevator car is higher than in <FIG>.

There are at least two different ways of providing a height adjustable roof construction. A first alternative is to provide one single roof element <NUM>' which can be attached in at least two alternative height positions to the elevator car <NUM>'. This has been illustrated in <FIG> by way of example. The roof element <NUM>' has attachment holes <NUM>' at two different vertical heights, so that bolts <NUM>' can protrude through the holes <NUM>' on the selected height and attach the roof element <NUM>' at a desired height position to the walls of the elevator car <NUM>'. Bolts and holes are naturally only one example of devices suitable for providing height adjustment for a single roof element <NUM>'. As an alternative, it is possible to utilize a mechanism which attaches the roof element to the elevator car and moves the roof element vertically when a lever is pulled, for instance.

Another alternative to provide a height adjustable roof construction is to utilize two different roof elements. In this alternative the first roof element <NUM>' illustrated in <FIG>, which provides an increased interior height for the elevator car <NUM>' is replaced by a second roof element <NUM>" as illustrated in <FIG>, when the increased interior height is no longer necessary. Again, attachment of the second roof element <NUM>" may be implemented with bolts <NUM>', for instance.

As is clear from <FIG>, while the building is constructed or there is for some other reason a need for transporting heavy and/or large sized cargo, the construction time modification for the elevator car <NUM>' can be implemented by setting the elevator car into the hybrid mode. In that case the rolling floor surface <NUM>, the one or more floor elements <NUM> and the increased interior height may be provided with the adjustable roof construction.

<FIG> illustrates in more detail an example of how the hoisting carried out with the hoisting machinery <NUM> and the rope <NUM> can be implemented. This solution can be utilized both for the embodiment of <FIG> and for the embodiment of <FIG>.

As can be seen from <FIG>, the rope <NUM> is led via pulleys <NUM>' and the hoisting machinery <NUM> in such a way that the elevator car <NUM>' is suspended from below. This leaves the upper part of the elevator car free, so that a height adjustable roof construction can be implemented.

<FIG> is a flow chart of a method for operating an elevator system. This method can be implemented for the embodiment of <FIG> or for the embodiment of <FIG>.

In step A the elevator car is set in a hybrid mode for the construction time of the building, for instance. This involves providing a floor of the elevator car with a rolling floor surface, and providing the elevator car with a floor section comprising one or more floor elements which are movable between a load bearing position, where the floor elements are aligned on top of the rolling floor surface, and a transport position, where the rolling floor surface is revealed in the elevator car.

Step B is not necessary in all implementations. However, in case an increased interior height is needed during the construction time, setting of the elevator car in the hybrid mode may include also step B. In that case the interior height of the elevator car is adjusted to an increased interior height. This may be implemented as has been explained in connection with <FIG>, for instance.

In step C, once the construction time modification is no longer needed, the elevator car is set in a person transport mode. This involves removing the rolling floor surface and the one or more floor elements from the elevator car to reveal the floor of the elevator car.

Step D is not necessary in all implementations. However, if the interior height of the elevator car has been increased with a step B, in step D the interior height of the elevator car can be adjusted to a lower height.

Claim 1:
An elevator system (<NUM>, <NUM>'), comprising:
a hoistway (<NUM>),
an elevator car (<NUM>, <NUM>') arranged in the hoistway, and
an elevator control (<NUM>) controlling the elevator car (<NUM>, <NUM>') to move vertically in the hoistway (<NUM>) between landings (<NUM>) of a building (<NUM>), wherein
a floor (<NUM>) of the elevator car (<NUM>, <NUM>') is provided with at least a first and a second roll (<NUM>) which are rotatably suspended in the elevator car for rotation around rotation axles (<NUM>) which are parallel to a door opening (<NUM>, <NUM>') of the elevator car to provide a rolling floor surface (<NUM>), characterized in that
a floor section comprising one or more floor elements (<NUM>) which are movable between a load bearing position, where the floor elements (<NUM>) are aligned on top of the rolling floor surface (<NUM>) and provide a fixed floor surface, and a transport position, where the rolling floor (<NUM>) surface is revealed in the elevator car (<NUM>, <NUM>').