Loft Ladder Assembly
A loft ladder assembly (10) is described which comprises a telescopically collapsible ladder (12) in combination with a frame (14) for mounting the ladder (12) within a hatch opening. The frame (14) comprises a mounting bracket (14a) to be secured in use to the hatch opening, to which bracket (14a) the uppermost section of the ladder (12) is pivotably connected, and a carriage (14b) pivotably connected to the mounting bracket (14a) for supporting the weight of the ladder (12) in its stowage position and preventing the ladder (12) from extending unintentionally.
The present invention relates to a loft ladder assembly.
BACKGROUND OF THE INVENTIONHatch doors are commonly provided in a ceiling to allow access to the loft or roof space of a building. Loft ladders are also known which are stored in the roof space and which are deployed by being pulled down after the hatch door has been opened.
Conventional loft ladders are usually of the extendable type. This means that the ladder is formed of two (or sometimes three) ladder sections arranged in different planes, which can slide over one another and can be locked to each other in a stacked and in an extended position. Even after the sections have been stacked, they are longer than the hatch door. Consequently, to stow away the ladder, it first has to be raised into the loft and then pivoted for its lower end to be able to pass through the hatch. The stacked ladder is normally pivoted about an axis, which is near its centre so that the ladder is nearly balanced. As a result, the ladder tends to stay in its horizontal position in the loft when the hatch door is opened and, to deploy it, a user must first pivot its lower end of the hatch and then release its various catches manually to allow it to be extended to reach the floor.
Because such ladders are not very compact, even in their stacked condition, they have the disadvantage of taking up roof space. It is therefore preferable to form the ladder as a telescopically collapsible ladder where the stiles are formed of sections that collapse into one another, as described for example in EP-B1-0 527 766. Such a ladder is more compact than an extendable ladder when it is collapsed and can be made sufficiently small to fit entirely within the hatch opening.
However, if the top rung of a telescopically collapsible ladder is pivoted on one side of the hatch opening, it will tend to drop and extend itself under the action of its own weight as soon as the hatch door is opened. This could cause injury to an unsuspecting user.
SUMMARY OF THE INVENTIONThe present invention therefore seeks to provide a loft ladder assembly that can fit within a hatch opening without taking up loft space and can be deployed and stowed away simply and safely.
According to the present invention, there is provided a loft ladder assembly which comprises a telescopically collapsible ladder in combination with a frame for mounting the ladder within a hatch opening, the frame comprising a mounting bracket to be secured in use to the hatch opening, to which bracket the uppermost section of the ladder is pivotably connected, and a carriage pivotably connected to the mounting bracket for supporting the weight of the ladder in its stowage position and preventing the ladder from extending unintentionally.
To prevent the ladder from extending under the action of its own weight, the carriage may be provided with means for releasably engaging the lowermost section of the ladder. The latter means may suitably comprise a pair of hooks for receiving lugs projecting laterally from the lowermost section of the ladder.
Preferably, the carriage is connected to the mounting bracket by means of at least one spring urging the carriage into the stowage position against the action of the weight of the ladder. Conveniently, each spring should be connected to the mounting bracket and the carriage in such a manner as to act as an over-centre toggle spring, so as to urge the carriage away from the ladder when the latter is deployed.
The collapsible ladder is preferably constructed in the manner taught by EP-B1-0 527 766. In particular, the ladder may have locking pins built into the rungs that are spring biases to move laterally outwards into holes formed in the stiles to lock the sections of the stiles together when the ladder is in its extended position, the locking pins for the next higher section of the ladder being retracted as the rung carrying the locking pins approaches the rung beneath it. When constructed in this manner, the ladder will open naturally from the top downwards when its lowermost section is released from the carriage and it will collapse in sequence from the lowermost section upwards as it is raised into its stowage position.
BRIEF DESCRIPTION OF THE DRAWINGSThe invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
A first embodiment of a loft ladder assembly 10 is shown in
The hatch opening is partially shown in
The ladder 12 is constructed in the same manner as a conventional telescopic ladder, which is currently commercially available under the trademark Telesteps®. Whilst such a construction of the ladder is preferred, it is not fundamental to the present invention and it will not therefore be described in detail in the present context. For further details on the internal construction of the ladder 12, reference may be made to EP-B1-0 527 766.
The Telesteps® ladder is preferred because it collapses from the bottom upwards and not from the top downwards. In particular, the ladder has locking pins built into its rungs, which are spring biased to move laterally outwards into holes formed in the stiles in order to lock the sections of the stiles together when the ladder is in its extended position. As two rungs come together, the lower rung presses on two levers 26 (shown of the second lowermost rung of
Each of the rungs of the ladder has two laterally projecting lugs 24, which engage in hooks 22 projecting from the carriage 14b. After the ladder has been fully collapsed, the lugs 24 of the second lowermost rung 33 can be lifted onto the hooks 22 and this prevents the ladder from extending under the action of its own weight.
The uppermost section of the ladder is pivoted relative to the mounting bracket 14a about pins 28 passing two limbs 20 that project from the mounting bracket 14a. Similarly, the carriage 14b is pivoted about pins 18 passing through two short ears 30 that project from the mounting bracket 14a.
The springs 16a and 16b are connected to bracket 14a and the carriage 14b in such a manner that as the carriage pivots downwards from the horizontal position shown in
In use, the ladder assembly is fixed by securing the mounting bracket 14a by bolts or screws to the ceiling joists surrounding and defining the hatch opening. When the hatch door 60 (only shown in
To deploy the ladder, the carriage 14b is pivoted downwards against the action of the springs 16a and 16b by pulling down on a strap 32 (shown in
When the ladder is stowed away, there remains a distance between its top two rungs. This allows the user to lift the entire ladder and thereby disengage the lugs 24 from the hooks 22. Once the weight of the ladder 12 is no longer supported by the hooks 22, it will extend naturally from the top downwards as can be seen in
To stow away the ladder, the above procedure is essentially reversed. First after using the levers 26 (partially shown in
With all the sections of the ladder 12 collapsed against one another, the lugs 24 of the second lowermost rung 33 can be raised onto the hooks 22 whereupon the weight of the ladder will be fully supported by the carriage 14b. While holding the strap 32 (only shown in
In
In
The loft ladder assembly of
To deploy the ladder, the carriage 14b is pivoted downwards against the action of the springs 16a and 16b by pulling down on a strap. This operation does not require much effort because of the leverage afforded by the carriage 14b. The beams 70 and the carriage 14b are pivoted past the over-centre position (see
From this position the user lifts the entire ladder and thereby disengages the hooks 122 from the bar 50 and the beams 70 are pivoted further. Once the weight of the ladder 12 is no longer supported by the bar 50, it will extend naturally from the top downwards similar to what can be seen in
To stow away the ladder, the above procedure is essentially reversed. First after using the levers on the second lowermost rung 33 of the ladder 12 to release the locking pins, the ladder is raised. As the rung 33 reaches the next higher rung, it will automatically release the locking pins of the next higher ladder section to collapse that ladder section. The process is repeated until the entire ladder is collapsed.
With all the sections of the ladder 12 collapsed against one another, the hook 122 of the lowermost rung 35 can be placed onto the bar 50 whereupon the weight of the ladder will be fully supported by the carriage 14b. While holding the strap, the beams and the carriage can now be pivoted towards its horizontal position and once it passes the over-centre position the strap is used to restrain the ladder so that it can be returned gently to its stowage position of
In
In the stowage position as shown in
From this position the user lifts the entire ladder and thereby disengages the hooks 122 from the bar 50 and the beams 70 are pivoted further. Once the weight of the ladder 12 is no longer supported by the bar 50, it will extend naturally from the top downwards similar to what can be seen in
To stow away the ladder, the above procedure is essentially reversed. First after using the levers on the second lowermost rung 33 of the ladder 12 to release the locking pins, the ladder is collapsed. As the rung 33 reaches the next higher rung, it will automatically release the locking pins of the next higher section to collapse that ladder section. The process is repeated until the entire ladder is collapsed.
With all the sections of the ladder 12 collapsed against one another, the beams can now be pivoted towards its horizontal position and once it passes the over-centre position the hook 122 of the lowermost rung can be placed onto the bar 50 whereupon the weight of the ladder will be fully supported by the frame 14. The strap is used to restrain the ladder so that it can be returned gently to its stowage position of
The lower part of the ladder 12 can also be releasably connected to the hatch door 60 so that the ladder 12 will pivot as the hatch doors opens.
The person skilled in the art will appreciate that various modifications may be made to the described loft ladder assembly without departing from the scope of the invention as set out in the appended claims. For example, the carriage 14b may carry or be connected to the hatch door. Furthermore, in place of springs, one could use a catch to hold the carriage in its raised position.
Claims
1-14. (canceled)
15. A loft ladder assembly for accessing a loft through a hatch opening, the loft ladder assembly comprising a telescopically collapsible ladder having a locking arrangement, being releasable, on one rung to collapse the ladder and a frame for mounting the ladder within the hatch opening, the frame comprising a mounting bracket secured to the hatch opening, connecting arrangements to pivotably connect the ladder to the frame and holding arrangements to hold the ladder in relation to the frame when the ladder is in a collapsed position, and the ladder having corresponding holding arrangements which interact with the holding arrangements on the frame.
16. The loft ladder assembly according to claim 15, wherein an uppermost section of the ladder is pivotably connected to the mounting bracket, and a carriage is pivotably connected to the mounting bracket for supporting a weight of the ladder, in a stowed position, and preventing the ladder from unintentionally extending.
17. The loft ladder assembly according to claim 15, wherein beams are pivotably connected to the frame, and an uppermost section of the ladder is pivotably connected to the beams.
18. The loft ladder assembly according to claim 17, wherein a carriage is pivotably connected to the mounting bracket for supporting a weight of the ladder, in a stowed position, and preventing the ladder from unintentionally extending.
19. The loft ladder assembly according to claim 18, wherein the carriage is provided with a means for releasably engaging a lowermost section of the ladder to prevent the ladder from extending under its own weight.
20. The loft ladder assembly according to claim 19, wherein the means for releasably engaging the lowermost section of the ladder comprises a pair of hooks for receiving lugs which project laterally from a second lowermost rung of the ladder.
21. The loft ladder assembly according to claim 17, wherein the ladder is provided with a means for releasably engaging the frame in order to prevent the ladder from extending under its own weight.
22. The loft ladder assembly according to claim 21, wherein the means for releasably engaging the frame comprises a hook section on a second lowermost rung of the ladder for receiving a vertical bar extending between the mounting brackets of the frame.
23. The loft ladder assembly according to claim 15, wherein, the ladder is provided with a means for releasably engaging a carriage in order to prevent the ladder from extending under its own weight.
24. The loft ladder assembly according to claim 23, wherein the means for releasably engaging the carriage comprises a hook section on a lowermost rung of the ladder for receiving a vertical bar connecting horizontal bars of the carriage.
25. The loft ladder assembly according to claim 17, wherein the beams are provided with a holding arrangement to prevent the ladder from extending under its own weight when in a stowed position.
26. The loft ladder assembly according to claim 15, wherein a carriage is connected to the mounting bracket by at least one spring urging the carriage into a stowed position against a weight of the ladder.
27. The loft ladder assembly according to claim 26, wherein each of the at least one spring is connected to the mounting bracket and to the carriage to act as an over-center toggle spring to urge the carriage away from the ladder when the latter is deployed.
28. The loft ladder assembly according to claim 15, wherein the ladder has locking pins built into the rungs, the locking pins are spring biased to move laterally outwards into holes formed in stiles to lock sections of ladder bars together when the ladder is in an extended position, the locking pins for a next higher section of the ladder being retracted as the rung carrying the locking pins approaches a rung beneath it.
Type: Application
Filed: Apr 15, 2005
Publication Date: Oct 11, 2007
Inventors: Per-Olof Eriksson (Tranas), Christer Johansson (Tranas)
Application Number: 11/578,525
International Classification: E04F 11/06 (20060101);