This disclosure relates to water vessel boarding ladders.
Water vessels may be boarded by users using a boarding ladder, which may also have built-in handles. A boarding ladder may be integrated into a hull of a vessel, or may be removable.
Boarding ladders are typically not always maintained in a deployed state on a vessel—meaning they are either deployed when in use, or closed and stowed away when not in use. Storing a boarding ladder may require the ladder to be folded or collapsed, and put in a storage box or other storage location. Vessels having integrated ladders may have storage boxes also integrated into the hull of a vessel where the ladders to be stored in, and deployed from. These types of devices are sometimes referred to as “mailbox” style boarding ladders (e.g., the ladder and/or handles are slide into, and out of, the storage box).
A common user frustration with boarding ladders is the amount of effort required to both deploy the ladder for use, then subsequently close (e.g., collapse and/or fold) the ladder for storage. These frustrations may be attributed to the weight of the boarding ladder and/or the awkward placement of the ladder on a vessel (e.g., on an outer hull), to name a few.
To address these and/or other problems, the present disclosure proposes a water vessel boarding ladder device which utilizes a unique configuration which provides a variable rotational relationship (and consequently torque transfer relationship) between a handle portion and a ladder portion thereof. The handle portion and the ladder portion may rotate simultaneous such that deployment and/or closure may be accomplished through user manipulation of rotating one or the other. The configuration providing the variable rotational relationship may assist a user in both the deployment and closure of the boarding ladder device, to achieve a safe and user friendly utilization thereof. The variability of the rotational relationship may be specially configured to provide a relationship that is suitable for a given position of the boarding ladder device that results in the safe and user-friendly operation.
For example, the handle portion may maintain a rotational advantage (e.g., the handle rotates relatively more than the ladder portion during the simultaneous rotation, or stated otherwise, the ladder portion rotates relatively less than the handle portion during the simultaneous rotation) over a majority of a rotation of the handle portion between the closed position and the deployed position. When rotating from the closed position, however, the handle portion's rotational advantage may decrease through an initial displacement (meaning the amount that the handle portion rotates relatively more than the ladder portion may decrease). Accordingly, as the handle portion is displaced from the closed position, the amount of corresponding displacement of the ladder portion continues to increase through the initial displacement. This may result in overall less effort, and more ease, to deploy from the closed position.
Further, when rotating from the deployed position, the handle portion's rotational advantage may increase through an initial displacement (meaning the amount that the handle portion rotates relatively more than the ladder portion may increase). Accordingly, as the handle portion is displaced from the deployed position, the amount of corresponding displacement of the ladder portion continues to decrease through the initial displacement. This may result in overall more effort to get the boarding ladder device out of the deployed position. However, this may be advantageous in that it may prevent unwanted closure that could otherwise occur from relatively minor displacement of the handle portion. For example, if a user is standing on a rung of the ladder portion and holding the handle portion, it may be undesirable for movement of the handle portion to result in rapid closure of the boarding ladder device.
One or more aspects of the present disclosure relate to a water vessel boarding ladder device comprising one or more of a ladder portion, a handle portion, a coupling portion, and/or other portions. The ladder portion may comprise one or more of a set of side rails, a set of rungs connected between the set of side rails, and/or other components. The handle portion may comprise a set of handles and/or other components. The coupling portion may comprise a set of couplings and/or other components. The set of couplings may connect the handle portion to the ladder portion. By way of non-limiting illustration, an individual coupling in the set of couplings may connect an individual side rail to an individual handle. The coupling portion may define a fixed axis around which the handle portion and the ladder portion simultaneously rotate during deployment and/or closure of the boarding ladder device. By way of non-limiting illustration, the handle portion and the ladder portion may be configured to rotate between a closed position and a deployed position of the boarding ladder device. The connection between the handle portion and the ladder portion provided by the coupling portion may cause the handle portion and the ladder portion to simultaneously rotate in opposite directions during the deployment and/or closure of the boarding ladder device. By way of non-limiting illustration, a rotation of the handle portion in a first direction may cause the ladder portion to rotate in a second direction opposite the first direction during simultaneous rotation.
In some implementations, the coupling portion may be configured to provide a variable rotational relationship between the handle portion and the ladder portion during the simultaneous rotation. The variable rotational relationship may facilitate transfer of rotational displacement from the handle portion to the ladder portion, and vis versa, that varies depending on a current position of the boarding ladder device.
By way of non-limiting illustration, when rotating from the closed position, the handle portion may have a rotational advantage over the ladder portion such that the handle portion may rotate relatively more than the ladder portion. Further, when rotating from the closed position, the rotational advantage may decrease through an initial displacement of the handle portion from the closed position.
By way of non-limiting illustration, when rotating from the deployed position, the handle portion may maintain the rotational advantage over the ladder portion such that the handle portion may rotate relatively more than the ladder portion. Further, when rotating from the deployed position, the rotational advantage may increase through an initial displacement of the handle portion from the deployed position.
These and other features and characteristics of the present technology, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. As used in the specification and in the claims, the singular form of “a” “an”, and “the” include plural referents unless the context clearly dictates otherwise.
The boarding ladder device 100 may be configured to be mounted on a water vessel (not shown in
It is noted that terms such as “posterior”, “anterior”, “forward”, “rearward”, “front”, “rear”, “upper”, “lower”, “distal”, “proximal”, “aft,” “stern,” “starboard,” “port,” “left”, “right,” “vertical,” and/or “horizontal” may refer herein to conventional directions when considering the device in an as-used position and/or based on the described use of various features. The use of these terms with various components should therefore be easily understood by a person skilled in the art as related to orientation, direction, and/or disposition. Further, some directions may be specifically defined herein and shown in the figures.
In
The individual side rails in the set of side rails may generally be formed from a tube, or set of telescopically engaged tubes, suitable for the intended purpose. By way of non-limiting illustration, an individual side rail may comprise a set of telescopically engaged segments of stainless steel tubing. In some implementations, an individual segment may be disposed between an individual rung. The telescopic engagement may allow the ladder portion 102 to collapse to a relatively smaller and more compact volume for stowage in a stowed mode (see, e.g.,
The set of rungs may include one or more rungs. By way of non-limiting illustration, the set of rungs may include one or more of a first rung 116, a second rung 118, a third rung 120, a fourth rung 122, a fifth rung 124, and/or other components. It is noted that the quantity of the rungs, spacing of rungs along the set of siderails, and/or width of the rungs, as shown in the figures and described herein are for illustrated purposes only, and not to be considered limiting. Instead, those skilled in the art may appreciate that fewer or more rungs may be utilized, and the spacing between them may be varied, as needed for a particular application the boarding ladder device 100. For example, the size of the vessel on which the boarding ladder device 100 is employed my impact the relative size and/or dimensions of the components of the boarding ladder device 100. In some implementations, the width of the rungs (and therefore spacing between the side rails) may be in the range of one quarter to one half a meter. In some implementations, the width of the rungs (and therefore spacing between the side rails) may be about 0.4 meters. In some implementations, the width of the rungs (and therefore spacing between the side rails) may be 0.4 meters. In some implementations, the width of the rungs (and therefore spacing between the side rails) may be about 0.5 meters. In some implementations, the width of the rungs (and therefore spacing between the side rails) may be 0.5 meters.
The handle portion 130 may comprise a set of handles and/or other components. The set of handles may comprise one or more of a first handle 132, a second handle 140, and/or other components. Individual handles in the set of handles may generally be formed from a tube or bar, made of material suitable for the intended purpose. By way of non-limiting illustration, an individual handle may comprise stainless steel tubing or substantially circular steel bar. It is noted that the quantity and/or length of the individual handles as shown in the figures and described herein are for illustrated purposes only, and are not to be considered limiting. Instead, those skilled in the art may appreciate that fewer or more handles may be utilized, and the spacing between them or length of an individual handle may be varied, as needed for a particular application the boarding ladder device 100. In some implementations, spacing between the handles may be substantially the same as the width of the rungs (and spacing between the side rails).
The first handle 132 may include one or more of a proximal end 134, a distal end 138 opposite the proximal end 134, and/or other features. The second handle 140 may include one or more of a proximal end 142, a distal end 144 opposite the proximal end 142, and/or other features.
The coupling portion 146 may be configured to connect the handle portion 130 to the ladder portion 102. The coupling portion 146 may be configured to connect the handle portion 130 and the ladder portion 102 to the storage portion 152. The coupling portion 146 may comprise a set of couplings and/or other components. The set of couplings may comprise one or more of a first coupling 148, a second coupling 150, and/or other components. The set of couplings may connect respective proximal ends of the handle portion 130 to the ladder portion 102. By way of non-limiting illustration, an individual coupling in the set of couplings may connect an individual side rail to an individual handle at respective proximal ends. For example, the first coupling 148 may connect the first side rail 104 to the first handle 132 at the respective proximal ends 106 and 134; the second coupling 150 may connect the second side rail 110 to the second handle 140 at the respective proximal ends 112 and 142.
In
Referring still to
The deployed position of the ladder portion 102 may be achieved through a rotation through angle “A2” relative the closed position (
In
Returning to
In some implementations, the variable rotation relationship may be established such that the handle portion 130 may maintain a rotational advantage over a majority of a rotation of the handle portion 130 between the closed position and the deployed position (e.g., majority of the rotation through angle A1 in
By way of non-limiting illustration, in some implementations, the handle portion 130 may maintain a rotational advantage over a minority of total rotation. Minority may include 49% or less of total rotation.
In some implementations, a rotational advantage may mean that the handle portion 130 rotates relatively more than the ladder portion 102 during the simultaneous rotation. That is, a ratio of rotational displacement (e.g., rotational displacement of the handle portion 130 over the rotational displacement of the ladder portion 102) may be greater than one. Stated otherwise, the ladder portion 102 may rotate relatively less than the handle portion 102 during the simultaneous rotate.
In some implementations, when rotating from the closed position (
In some implementations, the coupling portion 146 may be configured such that the rotational advantage of the handle portion 130 decreases through the initial displacement of the handle portion 130 from the closed position to a point where there is no advantage (e.g., the handle portion 130 and the ladder portion 102 rotate relatively the same), and/or the ladder portion 102 gains the rotational advantage over the handle portion 130. This point may be near an end of the initial displacement of the handle portion 130 from the closed position. In some implementations, “near” may mean +/−5 degrees. The ladder portion 102 may then rotate the same as (and/or relatively more than) the handle portion 130 following the point near the end of the initial displacement of the handle portion 130 from the closed position. The ladder portion 102 rotating the same as, and/or relatively more than, the handle portion 130 may define an intermediate displacement section of the rotational motion of the handle portion 130 between the closed and deployed position.
By way of non-limiting illustration, referring to
In some implementations, the intermediate displacement section, which starts at the end of the initial displacement from the closed position, may be defined with respect to a percentage of A1. By way of non-limiting illustration, the intermediate displacement section may comprise 15% to 25% of A1. By way of non-limiting illustration, the intermediate displacement section may comprise about 20% of A1. In some implementations, the intermediate displacement section may be defined with respect to degrees of rotation. By way of non-limiting illustration, the intermediate displacement section may comprise ten to twenty five degrees of rotation following the end of the initial displacement. By way of non-limiting illustration, the intermediate displacement section may comprise fifteen degrees of rotation. By way of non-limiting illustration, the intermediate displacement section may comprise twenty degrees of rotation.
As mentioned previously, the variable rotation relationship may be established such that the handle portion 130 may maintain the rotational advantage over a majority of a rotation of the handle portion 130 between the closed position and the deployed position. This majority may refer to rotational positions that are not within the intermediate displacement section, since that may be the section where they rotate the same as and/or the ladder portion 102 rotates relatively more than handle portion 130. Accordingly, if the intermediate displacement section comprises 15% A1 than the majority would refer to the remaining 85%. Further, if the intermediate displacement section comprises 25% A1 than the “majority” would refer to the remaining 75%, In some implementations, majority may refer to at least 51%.
In some implementations, the coupling portion 146 may be configured such that at a point in the intermediate displacement section, the rotational advantage of the handle portion 130 is again achieved, and continues to be maintained through the remainder of the simultaneous rotation. The point in the intermediate displacement section may comprise a local minima (ambient a maximum for the ladder portion's rotational advantage) and comprise a transition point where rotational advantage is gained back by the handle portion 130.
In
In some implementations, the coupling portion 146 may be configured such that the rotational advantage of the handle portion 130 increases through the initial displacement of the handle portion 130 from the deployed position to a point where the rotational advantage is at a local maxima. This point may be near an end of the initial displacement of the handle portion 130 from the deployed position. After the point of local maxima the rotational advantage of the handle portion 130 may decrease. The rotational advantage of the handle portion 130 may decrease from that point through second intermediate displacement section to the point in the intermediate displacement section comprising the local minima, passing through a point where the ladder portion 102 gains the rotational advantage over the handle portion 130, described above.
Thus, after overcoming the “locking” feature enabled by the coupling portion 146 at the deployed position, the configuration may thereafter provide an increase in the mechanical advantage to the ladder portion 102, thereby assisting a user in raising the ladder portion 102 for closure. This may be particularly advantageous if the ladder portion 102 is submerged in water.
By way of non-limiting illustration, referring to
In some implementations, the second intermediate displacement section, which starts at the end of the initial displacement from the deployed position, may be defined with respect to a percentage of A1. By way of non-limiting illustration, the second intermediate displacement section may comprise 35% to 65% of A1. By way of non-limiting illustration, the second intermediate displacement section may comprise about 45% of A1. In some implementations, the second intermediate displacement section may be defined with respect to degrees of rotation. By way of non-limiting illustration, the second intermediate displacement section may comprise twenty to seventy degrees of rotation following the end of the initial displacement from the deployed position. By way of non-limiting illustration, the second intermediate displacement section may comprise about forty five degrees of rotation.
It is noted that while some implementations described herein are in relation to the position of the handle portion 130, this is for illustrative purposes only since it may be common for users to deploy and close by grasping the handled, but are not to be considered limiting. Instead, the same or similar functionality may be achieved in the event that a user may instead apply forces to the ladder portion 102 when deploying or closing the boarding ladder device 100 such that the rotational displacement may be referred to relative the position of the ladder portion 102.
The configuration of the coupling portion 146 providing the variable rotational relationship may assist a user in both the deployment and closure of the boarding ladder device, as well as during rotation therebetween. The variability of the rotational relationship between the handle portion 130 and the ladder portion 102 may be specifically configured to provide a varying relationship that provides improvements in functionality for a given position of the boarding ladder device 100, and/or a relationship that changes at a desired rate from the closed to the deployed positions, that results in safe and user-friendly utilization.
In some implementations, the variable rotational relationship between the handle portion 130 and ladder portion 102 may be defined by a continuum of rotational advantage to the handle portion 102, which may be envisioned as a continuously changing ratio between the amount of rotational displacement of the handle portion 130 (“R1”) and the amount of rotational displacement of the ladder portion 102 (“R2”). For illustrative purposes, this rotational displacement ratio can be defined as R1:R2 (“R1 to R2” or “R1 over R2”). It is noted that the torque ratio may be an inverse of the rotational displacement ratio. As mentioned, it is envisioned that the majority of the rotational displacement of the handle portion comprises a situation where R1:R2 is greater than one. Accordingly, the intermediate displacement section may be where R1:R2
In some implementations, at the instant of rotating from the closed position (
In some implementations, at the instant of rotating from the deployed position (
In some implementations, within the intermediate displacement section, the ratio may be in the range of about 1:1 to 1:1.5 and/or other ranges. In some implementations, at the instant of being at the local minima within the intermediate displacement section, the ratio may be in the range of 1:1.1 to 1:1.3. In some implementations, at the instant of being at the local minima, the ratio may be about 1.1.1.
In some implementations, at the instant of being at the local maxima at the end of the initial displacement from the deployed position, the ratio may be in the range of 1.25:1 to 2:1. In some implementations, at the instant of being at the local maxima, the ratio may be about 1.5:1.
It is noted that while various examples of values and/or ranges are provided herein, this is for illustrative purposes only and is not to be considered limiting
Various mechanisms and/or devices may be used to achieve the variable rotational relationship between the handle portion 130 and ladder portion 102, in accordance with one or more implementations presented herein. Such mechanisms and/or devices may be configured to provide variable mechanical advantages, and/or rotational advantages, in accordance with the features and/or functionality described herein.
By way of non-limiting illustration, in some implementations, the coupling portion 149 may be envisioned to employ a cam (or cams) that are sized, shaped, and/or arranged to cause the variable rotational relationship described herein. In some implementations, the coupling portion 146 may be envisioned to employ a series of gears, where different gears are shifted to depending on the position the handle portion 130 and ladder portion 102 to cause the variable rotational relationship described herein. In some implementations, the coupling portion 146 may utilize a linkage configuration to cause the variable rotational relationship described herein. The linkage configuration may include one or more of a four-bar linkage configuration, a five-bar linkage configuration, a six-bar linkage configuration, and/or other configurations. By way of non-limiting illustration, an individual coupling connecting an individual side rail to an individual handle may comprise a four-bar linkage configuration and/or other configuration. For illustrative purposes, a four-bar linkage configuration will now be described as shown in the
Generally, a four-bar linkage may be comprised of one or more of a fixed link (or frame), an input link, coupler link, an output link, and/or other components. The input link may be coupled to the fixed link via a first fixed pivot. The output link may be coupled to the fixed link via a second fixed pivot. The coupler link may be connected between distal ends of the input link and the output link. The connection between the coupler link and the distal end of the input link may define a first moving pivot. The connection between the coupler ink and the distal end of the output link may define a second moving pivot.
The support plates 504 and 506 may provide rigidity and strength to the coupling portion. One or both support plates 504 or 506 may be coupled to a guide rail and/or other components which allow individual couplings to slide into and out of the storage portion (not shown in
The support plates 504 and 506 may define a set of fixed pivots (including first fixed pivot 508 and second fixed pivot 510) which mount the proximal ends 106 and 134 to the support plates 504 and 506. The first fixed pivot 508 and second fixed pivot 510 may be formed by one or more of pins, screws, bolts, and/or other components extending through one or both plates. The support plates 504 and 506 may include a stop element 512. The stop element 512 may be engaged by one of the linkage components of the coupling 502 at the open position to prevent further rotation. The stop element 512 may comprise one or more of a pin, a screw, a bolt, and/or other components.
In some implementations, support plate 506 (and/or plate 504) may define a fixed link, or frame, of the four-bar linkage configuration 502. In particular, the fixed link may be visualized as a line segment between first fixed pivot 508 and second fixed pivot 510. The four-bar linkage configuration 502 may be comprised of one or more of a first tang 602, a second tang 608, a coupler link 618, and/or other components.
In
The proximal end 106 of the first side rail 104 may include and/or be integrally coupled to the second tang 608, and/or other components. The second tang 608 may bifurcate into a clevis portion 616 and a stopper portion 610. The second tang 608 may be coupled to the support plate 506 via the second fixed pivot 510. The second tang 608 may define an output link of the four-bar configuration. The clevis portion 616 may project from the second tang 608 to form the output link of the second tang 608. In particular, the output link may be visualized as a line segment between fixed pivot 510 and a second moving pivot 624 at the clevis portion 616. The second tang 608 may project from the proximal end 106 along a same line or direction as the first side rail 104. In some implementations, the clevis portion 616 may be disposed at an angle in the range of sixty to eighty degrees relative to the direction of the second tang 608. In some implementations, the clevis portion 616 may be disposed at an angle of about sixty five degrees relative to the direction of the second tang 608. The stopper portion 610 may be formed and arranged to engage the stop element 512 at the open position to prevent further rotation, as shown in
The coupler link 618 may include a first end 620 connected to the clevis portion 604 of the first tang 602. The connection of the coupler link 618 to the clevis portion 604 of the first tang 602 may define the first moving pivot 622 of the four-bar linkage configuration 502. For example, the coupler link 618 may be attached within the clevis portion 604, and secured via a clevis pin. In some implementations, the coupler link 618 may be in the range of one to six centimeters in length. In some implementations, the coupler link 618 may be in the range of two to five centimeters in length. In some implementations, the coupler link 618 may be in the range of two and a half to three and a half centimeters in length. In some implementations, the coupler link 618 may be about three centimeters in length. In some implementations, “about” may mean +/−one millimeter. In some implementations, the coupler link 618 may be three centimeters in length.
The coupler link 618 may include a second end (not shown in the figure) connected to a distal end 612 of the second tang 608. The distal end 612 of the second tang 608 may be the distal end of the clevis portion 616, as opposed to a distal end of the stopper portion 610. The connection of the coupler link 618 to the distal end 612 of the second tang 608 (e.g., clevis portion 616) may define the second moving pivot 624 of the four-bar linkage configuration 502. For example, the coupler link 618 may be attached within the clevis portion 616 and secured via a clevis pin.
The segment A-B may represent the initial displacement of the handle portion from the closed position. As shown, when rotating from the closed position, the rotational advantage decreases through the initial displacement of the handle portion, as illustrated by the downward slope of segment A-B.
The segment B-D may represent the intermediate displacement section where the ladder portion has the rotational advantage and/or there is no advantage. For example, when rotating from the closed position (e.g., going left to right on the page) point B may represent a transition point where the rotational advantage switches from the handle portion to the ladder portion. Conversely, when rotating from the deployed position (e.g., going right to left on the page) point B may represent a transition point where the rotational advantage switches from the ladder portion to the handle portion. When rotating from the closed position (e.g.; going left to right on the page) point D may represent a transition point where the rotational advantage switches from the ladder portion back to the handle portion. Conversely, when rotating from the deployed position (e.g., going right to left on the page) point D may represent a transition point where the rotational advantage switches from the handle portion to the ladder portion. The positions between points B and D may represent positions where the ladder portion may have a slight rotational advantage. The local minima, point C, may occur after the initial displacement of the handle portion from the closed position (A-B) to represent an ending of the decrease of the rotational advantage through the initial displacement of the handle portion from the closed position.
The segment F-E may represent the initial displacement of the handle portion from the deployed position. As shown, when rotating from the deployed position, the rotational advantage increases through the initial displacement of the handle portion, as illustrated by the upward slope of segment F-E. The initial displacement of the handle portion from the deployed position may end at the local maxima; point E.
When rotating from the deployed position, after point E the rotational advantage of the handle portion may decrease, as illustrated by the downward slope of segment E-D. The segment E-D may represent the second intermediate displacement section, where there is a decrease in rotational advantage from point E to the local minima (point C), passing through point D where the ladder portion gains the rotational advantage over the handle portion.
It is noted that the graph shown in
In some implementations, method 1100 may be implemented using manual and/or automated manufacturing techniques. A manual manufacturing techniques may include one or more techniques used by skilled artisans in manufacture of boarding ladders made of metal and/or other suitable materials. A technique may include one or more of cutting, riveting, welding, bolting, screwing, drilling, and/or other manual technique. Other techniques known to skilled artisans in boarding ladder manufacture are also within the scope of the present disclosure. An automated manufacturing technique may include machines (e.g., extruders, printers, industrial robots, etc.) and/or one or more processing devices. The one or more processing devices and/or machines may include one or more devices executing some or all of the operations of method 1100 in response to instructions stored electronically on an electronic storage medium. The one or more processing devices and/or machines may include one or more devices configured through hardware, firmware, and/or software to be specifically designed for execution of one or more of the operations of method 1100.
An operation 1102 may include forming a ladder portion comprising a set of side rails, a set of rungs connected between the side rails, and/or other components.
An operation 1104 may include forming a handle portion comprising a set of handles and/or other components.
An operation 1106 may include forming a coupling portion comprising a set of couplings and/or other components.
An operation 1108 may include connecting the handle portion to the ladder portion via the coupling portion. An individual side rail in the set of side rails may be connected to an individual handle in the set of handles via an individual coupling in the set of couplings. The coupling portion may define a fixed axis around which the handle portion and the ladder portion simultaneously rotate. The handle portion and the ladder portion may be configured to rotate between a closed position and a deployed position of the boarding ladder device. The connection between the handle portion and the ladder portion may cause the handle portion and the ladder portion to rotate in opposite directions such that a rotation of the handle portion in a first direction causes the ladder portion to rotate in a second direction opposite the first direction during simultaneous rotation. The coupling portion may be formed to provide a variable rotational relationship between the handle portion and the ladder portion during the simultaneous rotation. By way of non-limiting illustration, when rotating from the closed position, the handle portion may have a rotational advantage over the ladder portion such that the handle portion rotates relatively more than the ladder portion, and the rotational advantage may decrease through an initial displacement of the handle portion from the closed position. By way of non-limiting illustration, when rotating from the deployed position, the handle portion may maintain the rotational advantage over the ladder portion such that the handle portion rotates relatively more than the ladder portion, and the rotational advantage may increase through an initial displacement of the handle portion from the deployed position.
Although the present technology has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred implementations, it is to be understood that such detail is solely for that purpose and that the technology is not limited to the disclosed implementations, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present technology contemplates that, to the extent possible, one or more features of any implementation can be combined with one or more features of any other implementation.
Number | Name | Date | Kind |
---|---|---|---|
5085165 | Reed | Feb 1992 | A |
6789648 | Cook | Sep 2004 | B2 |
6904863 | Mardikian | Jun 2005 | B2 |
7025174 | Hawley | Apr 2006 | B1 |
8075008 | Hanser | Dec 2011 | B1 |
9302719 | Krishnan | Apr 2016 | B1 |
20180215304 | Jevaney | Aug 2018 | A1 |
Entry |
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https://www.nautinox.it/en/shop/ladders-for-boats-and-rib-boats/ladder-2375/ladder-2375/ (2016) retrieved from the internet on Nov. 18, 2022. pp. 1-4. |