Retractable ladder assembly

Information

  • Patent Grant
  • 6789648
  • Patent Number
    6,789,648
  • Date Filed
    Wednesday, January 8, 2003
    21 years ago
  • Date Issued
    Tuesday, September 14, 2004
    20 years ago
Abstract
A retractable ladder assembly for marine applications having a frame and a ladder having a pair of channel members pivotally connected to the frame and extendible there from in a vertical position and in a horizontal position. A plurality of rung members extend between the channel members, and channel extension members are slidably supported in the channel members. A pair of strut connectors have one end pivotally connected to the frame and the other end pivotally connected to the lower ends of the channel extension members. A power actuator is supported by the frame to pivot the channel members between a vertical position and a horizontal position, the channel extension members extending from the upper ends of the channel members in the vertical position and are contained in the channel members in the horizontal position.
Description




FIELD OF INVENTION




The present invention relates generally to the field of folding ladders and the like, and in particular but not by way of limitation, to a retractable ladder assembly for use in marine applications such as pontoon type boats and platforms.




BACKGROUND OF INVENTION




Boarding a pontoon boat from the water on which the boat is floating, or pulling oneself from a body of water to a dock platform, presents a challenging physical problem to many people. Without the use of a ladder, this task can be quite difficult in the least, so detachable ladders have frequently been utilized to facilitate such activity. However, detachable manual ladders are heavy, cumbersome and often too large to be stowed on the boat or near the dock.




Furthermore, detachable ladders that are used on decks or other marine platforms often are left out and not returned to storage after usage, cluttering passageways and can create unsafe obstructions to traffic. Further, storage locations for ladders often are inconvenient, distant or time consuming to accommodate.




Thus, it is clear that there is a need for ladders that can be deployed in marine locations where space is restricted or where other environmental conditions make the use of conventional ladders difficult and impractical. For example, for many people, especially elderly and physically challenged persons, the handling for deployment and stowage of conventional ladders is a struggle, and especially unsafe in marine environments where maneuvering space is restricted. There are many such marine locations where it would be desirable to have a deployable ladder that can be readily stowed in instant, off deck storage.




There is therefore a continuing need for an accurate and fast method to deploy and store a ladder in marine and other environments where space is restricted and storage difficult and/or inconvenient, where manual deployment and storage return bring risk of unsafe practices, and to address other limitations associated with the current state of the art.




SUMMARY




The present invention provides for marine applications having a frame, and a ladder having a pair of channel members pivotally connected to the frame and extendible there from in a vertical position and in a horizontal position. A plurality of rung members extend between the channel members, and channel extension members are slidably supported in the channel members. A pair of strut connectors have one end pivotally connected to the frame and the other end pivotally connected to the lower ends of the channel extension members.




A power actuator is supported by the frame to pivot the channel members between a vertical position and a horizontal position, the channel extension members extending from the upper ends of the channel members in the vertical position and are contained in the channel members in the horizontal position.




The components of the retractable ladder assembly are selected to be corrosion resistant for marine environments.




Other features, benefits and advantages which characterize the claimed invention will become apparent upon reading the following detailed description in view of the associated drawings and appended claims.











BRIEF DESCRIPTION OF DRAWINGS AND APPENDIXES





FIG. 1

is perspective view of a retractable ladder assembly constructed in accordance with the present invention and shown mounted to the stem of a pontoon boat in the extended position.





FIG. 2

is a perspective view of the retractable ladder assembly of

FIG. 1

in the retracted position.





FIG. 3

is a top plan view of the retractable ladder assembly of

FIG. 1

in the extended position.





FIG. 4

is a front, elevational view of the retractable ladder assembly of

FIG. 1

in the extended position.





FIG. 5

is a side, elevational view of the retractable ladder assembly of

FIG. 1

in the extended position.





FIG. 6

is a side, elevational view of the retractable ladder assembly of

FIG. 1

in the retracted position





FIG. 7

is a perspective, exploded view of the retractable ladder assembly of FIG.


1


.





FIG. 8

is a diagrammatical representation of the control of the retractable ladder assembly of FIG.


1


.











DESCRIPTION




Referring to the drawings in general, and more particularly to

FIG. 1

, shown therein is a retractable ladder assembly


10


constructed in accordance with the present invention. As will be discussed herein, the retractable ladder assembly


10


is constructed so as to have a retracted position and an extended position. The retractable ladder assembly


10


in

FIG. 1

, attached to a boat deck


12


, is in the extended position with an upper portion


14


above the water and a lowered portion


16


partially extending into the water


18


.

FIG. 2

is a similar view and shows the retractable ladder assembly


10


in the retracted position under the boat


12


. While illustrated attached to a boat stren, such as a pontoon boat, it will be appreciated that the retractable ladder of the present invention can as well be installed any suitable marine platform, such as a dock.




With reference now to

FIGS. 3 through 6

, the retractable ladder assembly


10


has a frame


20


with a mounting apparatus


22


, a hinge


24


and a power actuator


26


supported thereby. The power actuator


26


can be any one of a number of commercially available actuators suitable for the purpose described herein. One such power actuator that has been found acceptable for the present invention is manufactured by Cook Manufacturing Inc., Duncan, Okla., the assignee of the present invention, and is described in now pending U.S. patent application Ser. No. 09/641,586 entitled “Hydraulic Actuator,” filed Aug. 18, 2000, and assigned to the assignee of the present invention, the teaching of such patent application being herewith incorporated by reference.




As shown in

FIGS. 4 and 5

, the retractable ladder assembly


10


has a ladder


28


connected via the hinge


24


to the frame


20


. The ladder


28


has an upper portion


30


and a lower portion


32


that are above and below the hinge


24


, respectively, when the ladder


28


is in the deployed or extended position depicted in FIG.


4


. The lower portion


32


is pivotally attached to the frame


20


via the hinge


24


, which comprises a pair of pivot brackets


34


. The upper portion


30


comprises a pair of longitudinally extending, channel extension members


36


.




The lower portion


32


of the ladder


28


has a pair of channel members


38


held in spaced apart parallel disposition by interposed rung members


40


. The channel members


38


are configured to slidably receive the channel extension members


36


therein; that is, each of the channel extension members


36


is slidably disposable in one of the channel members


38


.




As shown in

FIG. 5

, each of the channel members


38


has a channel profile in which one of the channel extension members


36


in slidingly received. Each of a pair of strut connector members


42


has one end thereof pivotally connected to the lower end of one of the channel extension members


36


by a roller connector


44


. Also, the other end of each of the strut connector members


42


is pivotally pinned to the frame


20


by a pin connector


46


.




The frame


20


has a cross member


48


, and the power actuator


26


is mounted on the underside of the cross member


48


as shown. A cross member


52


is attached to the upper ends of the channel members


38


, the pivot brackets


34


connected to the cross member


52


to pivotally attach the channel members


38


to the frame


20


. The power actuator


26


has an extendible rod


50


that is pivotally connected via a clevis connection to the cross member


52


, and the power actuator


26


is disposed such that when the extendible rod portion


50


is retracted, the cross member


52


and attached channel members


38


fold beneath the frame


20


to assume a horizontal position as depicted in FIG.


6


. When the extendible rod portion


50


of the power actuator


26


is extended, the cross member


52


and attached channel members


38


fold out to be disposed substantially perpendicular to the frame


20


, and thus vertical, as depicted in FIG.


5


.




Since the channel extension members


36


are slidably supported in the channel members


38


and are pivotally connected to the strut connector members


42


, the channel extension members


36


are disposed beneath the frame


20


when the power actuator


26


is in the rod retracted position. The channel extension members


36


will be disposed in a substantially perpendicular (or vertical) position when the power actuator


26


is in the rod extended position.




That is, the ladder


28


, in its extended position, will be substantially perpendicular to the boat deck


12


, while the ladder


28


will be in a substantially horizontal, folded position in its retracted position. In this latter mentioned retracted position, the upper portion


30


slides together with the lower portion


32


as the power actuator


26


retracts so that the ladder


28


assumes the folded or retracted position under the boat deck


12


, as shown in FIG.


6


. And when the power actuator


26


extends, the upper portion


30


is caused to slide along the lower portion


32


as these pivot outwardly so that the ladder


28


will assume the extended position of FIG.


5


.




As mentioned, the retractable ladder assembly


10


is shown in the retracted position in

FIG. 6

, having the ladder


28


stored beneath the frame


20


. In this position, the power actuator


26


is retracted and the connector members


42


are positioned substantially parallel to, and beneath, the frame


20


and thus beneath the boat deck or platform


12


to which the frame


20


is mounted. And it should be noted that both the upper portion


30


and the lower portion


32


of the ladder


28


are tucked beneath the frame


20


and thus under the boat deck


12


to which the frame


20


is mounted.





FIG. 7

provides a list of parts that make up the retractable ladder assembly


10


. Not all of the parts are separately designated as such is not believed necessary for the present disclosure to be understood to one skilled in the art; however, the components described hereinabove are numerically designated in

FIG. 7

, including the frame


20


, ladder


28


, power actuator


26


and strut connectors


42


.




The power actuator


26


is provided preferably with an extend limit switch (not shown), and a retract limit switch (also not shown) respectively senses maximum travel at the end of the stroke of the extendible rod


50


thereof both in the extended and the retracted positions. As depicted in

FIG. 8

, a control toggle switch


60


is provided and electrically connected to the power actuator


26


such that, when closed downwardly, an extend signal is sent to the power actuator


26


to cause the ladder


28


to move to its extended position. As the extendible rod


50


of the power actuator


26


extends, both limit switches close. At the end of the travel stroke of the extendible rod


50


in that direction, the extend limit switch opens a control circuit (not shown) for the extend direction to stop the power actuator


26


. In this state, the retract limit switch remains closed, which allows for operation in the retract direction.




When the control toggle switch


60


is closed upwardly to a storage or stow position, a retract signal is sent to the power actuator


26


to retract the extendible rod


50


and cause the ladder


28


to go to its retracted position. Again, as the power actuator


26


moves, both limit switches close. At the end of travel in that direction the retract limit switch opens the control circuit for the retract direction and the power actuator


26


stops. In this state, the extend limit switch remains closed, which allows for operation in the extend direction.




Down (Deploy) Operation




With the control toggle switch


60


in the up position, the retractable ladder assembly


10


is in the retracted or stowed position tucked under the boat deck


12


, as shown in FIG.


6


. To move the ladder


28


to the lowered or vertical position as shown in

FIG. 5

, the toggle switch


60


is moved to the down position, which starts the power actuator


26


to extend the ladder


28


toward the extended or vertical position. When the power actuator


26


reaches its end of travel, the ladder


28


is vertical, the down limit switch opens and the power actuator


26


stops. The ladder


28


is then ready to be used by personnel.




Up (Stow) Operation




With the retractable ladder assembly


10


in the extended or deployed position, the ladder


28


is vertically disposed and the toggle switch


60


is in the down position. To move the ladder


28


to the up or horizontal position, the toggle switch


60


is moved to the up position, starting the power actuator


26


to retract and thereby swing the ladder


28


toward the up or horizontal position. When the power actuator


26


reaches the end of travel, the ladder


28


is in the horizontal or retracted position, as shown in

FIG. 6

, and the up limit switch opens and the power actuator


26


stops. The ladder


28


is then in the retracted, stowed position under the boat deck


12


.




Preferably, the materials of construction of the components of the retractable ladder assembly are selected to be corrosion resistant for marine environments.




It is clear that the present invention is well adapted to achieve the ends, benefits and advantages mentioned and those inherent herein. While a presently preferred embodiment of the invention has been described in varying detail for purposes of the disclosure, it will be understood that numerous changes may be made which will readily suggest themselves to ones skilled in the art and which are encompassed within the spirit of the invention disclosed and as defined by the above text and the accompanying drawings.



Claims
  • 1. A retractable ladder assembly for extension from, and stowage under, a marine platform, the retractable ladder assembly comprising:a frame supportable under the marine platform; a ladder comprising; a pair of channel members pivotally connected to the frame and extendible there from in a vertical position and in a horizontal position, a plurality of rung members extending between the channel members; and at least one channel extension member slidably supported in the channel members; at least one strut connector having one end pivotally connected to the frame and the other end pivotally connected to the lower end of the channel extension member; and actuator means supported by the frame for pivoting the channel members between the vertical position and the horizontal position, the channel extension member extending from the upper end of the channel member in the vertical position and contained in the channel member in the horizontal position.
  • 2. The assembly of claim 1 wherein ladder has a pair of channel extension members, each of the channel extension members slidably supported in one of the channel members.
  • 3. The assembly of claim 2 wherein the channel members and channel extension members are substantially parallel.
  • 4. The assembly of claim 3 wherein the actuator means comprises a power actuator having an extendible rod, the distil end of the extendible rod pivotally connected to the channel members near an upper end thereof.
  • 5. The assembly of claim 4 further comprising a control toggle switch connected to the power actuator and having an extend position in which an extend signal is sent to the power actuator to extend the extendible rod, and having a storage position in which a retract signal is sent to the power actuator to retract the extendible rod.
  • 6. The assembly of claim 5 further comprising a cross member connected to the upper ends of the channel members, and at least one bracket connected to the cross member and pivotally connected to the frame, the distal end of the extendible rod pivotally connected to the cross member.
  • 7. The assembly of claim 6 wherein the ladder is made of a material that resists corrosion in a marine environment.
  • 8. A retractable ladder assembly comprising:a frame; a ladder comprising: a first channel member; a second channel member; means for pivotally connecting the first and second channel members to the frame; a plurality of rung members extending between and supported by the first and second channel members; a pair of channel extension members, each of the channel extension members slidably supported in one of the first and second channel members; a pair of strut connectors having first and second ends, the first end of each strut connectors pivotally connected to the frame and the second end of each strut connectors pivotally connected to the lower end of one of the channel extension members; and actuator means supported by the frame for pivoting the first and second channel members between a vertical position and a horizontal position, the channel extension members extending from the upper ends of the first channel member and the second channel member when in the vertical position and contained in the first and second channel members when in the horizontal position.
  • 9. The assembly of claim 8 wherein the channel members and channel extension members are substantially parallel.
  • 10. The assembly of claim 8 wherein the actuator means comprises a power actuator having an extendible rod, the distil end of the extendible rod pivotally connected to the channel members near an upper end thereof.
  • 11. The assembly of claim 10 further comprising a control toggle switch connected to the power actuator and having an extend position in which an extend signal is sent to the power actuator to extend the extendible rod, and having a storage position in which a retract signal is sent to the power actuator to retract the extendible rod.
  • 12. The assembly of claim 11 further comprising a cross member connected to the upper ends of the channel members, and at least one bracket connected to the cross member and pivotally connected to the frame, the distal end of the extendible rod pivotally connected to the cross member.
  • 13. The assembly of claim 8 wherein the ladder is made of a corrosion resistive material for a marine environment.
RELATED APPLICATION

This application claims priority to U.S. Provisional Application No. 60/346,948 filed Jan. 8, 2002 entitled “Retractable Ladder Assembly.”

US Referenced Citations (4)
Number Name Date Kind
3305045 Schlecht Feb 1967 A
4205862 Tarvin Jun 1980 A
4708355 Tiede Nov 1987 A
4896744 Crone Jan 1990 A
Foreign Referenced Citations (1)
Number Date Country
03090493 Apr 1991 JP
Provisional Applications (1)
Number Date Country
60/346948 Jan 2002 US