1. Field of the Invention
The present invention relates to the field of farm implements and, more particularly, to a farm implement with a ladder that has retractable features that allow for additional comfort and safety over existing ladders.
2. Description of the Background Art
In the agricultural industry, wagons, grain carts, seed tenders, and bins may have one or more ladders attached to the outside of the implement. These ladders may be used by an operator to inspect portions of the implement that are not easily observed from the ground. For example, in a grain cart or seed tender with a bin for storing agricultural material, the ladder may be used to visually determine an amount of agricultural material in the bin. Current ladders may be fixed to the implement in a stationary manner, or they may include a fixed upper portion and a movable lower portion that can be extended downwardly from the fixed upper portion for easier operator access. In the latter case, the fixed upper portion of the ladder is typically vertical and is positioned close to the implement to maintain an acceptable profile for transport and storage. The movable lower portion can be retracted when not in use to prevent any interactions between the ladder and the rest of the implement and to provide ground clearance during transport.
Current ladders are useful but they have a number of disadvantages. These include restricted foot area and awkward positioning that makes it inconvenient for operators to inspect the implement. As such, there is a need for an improved ladder on farm implements.
In accordance with a first aspect of the invention, a farm implement includes a ladder with movable upper and lower portions configured to assume an easily accessible and convenient position relative to the implement in an extended position and a compact profile in a retracted position. In an embodiment, the ladder includes an upper ladder portion and a lower extension ladder or portion, connected to the upper ladder. The apparatus includes a lower pivot link connecting the upper ladder to a farm implement. The apparatus may also include a latch connecting the lower ladder extension to the upper ladder. The release of the latch results in moving the lower ladder extension away from the upper ladder while simultaneously moving the upper ladder and the lower pivot link. In an embodiment, the lower pivot link is connected to the upper ladder portion via a pivoting step.
In accordance with second aspect of the invention, a method of operating a ladder on a farm implement includes releasing a latch associated with a ladder connected to the farm implement. The method further includes pulling a lower ladder extension or portion away from a lower end of an upper ladder portion. The method further includes that pulling of the lower ladder extension results in an upper portion of the ladder to move about a pivot and a lower pivot link to move about another pivot that causes the lower pivot link and the upper portion of the ladder to move away from the device. In an embodiment, pulling the lower ladder extension downwardly may also cause a pivoting step to assume a position in which it defines a rung of the upper ladder portion.
In accordance with a third aspect of the invention, a farm implement includes a container and a ladder for climbing in relation to the container. The ladder includes an upper ladder portion having upper and lower ends, the upper end of the upper ladder portion being pivotably connected to the container via a first pivot defining a first horizontal pivot axis about which the upper ladder portion is pivotable between a retracted position against the container and an extended position angled away from the container. The ladder also includes a lower ladder portion having first and second ends, the first end of the lower ladder portion being pivotably connected to the lower end of the upper ladder portion via a second pivot defining a second horizontal pivot axis about which the lower ladder portion is pivotable between a folded position extending upwardly along the upper ladder portion and an unfolded position extending downwardly from the upper ladder portion. The ladder also includes a movable pivot link having an outer end pivotably connected to the lower end of the upper ladder portion via a third pivot defining a third horizontal pivot axis. The upper ladder portion also includes a pivoting step connected to the movable pivot link via the third pivot and connected to the upper ladder via a fourth pivot defining a fourth horizontal pivot axis about which the pivoting step is pivotable between retracted and extended positions.
In an embodiment, the container includes a lower inclined wall extending inwardly and downwardly from an upper side wall. In an embodiment, the upper ladder portion bends inwardly at or below the junction between the upper side wall and lower inclined wall of the container to provide a narrower profile in the retracted position. In an embodiment, the farm implement may also include a frame. In an embodiment, the movable pivot link includes a pair of links extending in parallel from the frame to the upper ladder portion and the pair of links are connected by a cross member to improve lateral stability. In an embodiment, the movable pivot link extends upwardly from the frame to the pivoting step and the pivoting step in the retracted position is parallel to the upper ladder portion and in the extended position is perpendicular to the upper ladder portion. In an embodiment, the movable pivot link extends upwardly from the frame of the farm implement to the pivoting step at a pivot-link angle relative to horizontal. In an embodiment, the pivot-link angle is 60° in the retracted position and 30° in the extended position
In an embodiment, the lower ladder portion is pivotally connected to the pivoting step by a pair of short links that cause the lower ladder portion and the pivoting step to move together between the folded and the unfolded positions. In an embodiment, in the extended position the upper ladder portion extends outwardly and downwardly at an angle relative to vertical and the lower ladder portion extends from the upper ladder portion at the same angle, and in the retracted position the upper and lower ladder portions are adjacent to or inwardly spaced from an outer dimension of the farm implement. In an embodiment, the upper end of the upper ladder portion is pivotally connected to a bracket configured to be mounted on a surface of the container, the bracket including a mounting plate and a pair of vertical flanges extending perpendicularly outwardly from vertical edges of the mounting plate, and the upper ladder portion is connected to the flanges at the first pivot. In an embodiment, the first horizontal pivot axis is parallel to a side wall of the container. In an embodiment, the third and fourth horizontal axes of rotation are parallel to the first horizontal axis of rotation. In an embodiment, the second horizontal axis of rotation is parallel to and below the fourth horizontal axis of rotation.
In an embodiment, the upper ladder portion includes a pair of parallel upper uprights and a plurality of upper rungs extending transversely between the upper uprights at vertically spaced intervals to define steps. In an embodiment, the lower ladder portion includes a pair of parallel lower uprights and a plurality of lower rungs extending transversely between the lower uprights at vertically spaced intervals to define steps, and the lower uprights are pivotally connected to the upper uprights at the second pivot. In an embodiment, the pivoting step is deeper than the upper and lower rungs and is configured to be pivotable between a retracted position extending parallel to the upper uprights and an extended position extending inwardly at an angle from the upper uprights. In an embodiment, the upper uprights include a channel with a channel wall and the lower uprights are received within the channel and channel notches formed in the channel wall so that the upper rungs are received in the channel notches when the lower ladder portion is folded upwardly against the upper ladder portion in the retracted position.
In an embodiment, the farm implement also includes a latch mechanism for locking the latter in the retracted position. In an embodiment, the latch mechanism includes one or more spring-biased levers mounted on the lower ladder portion and having a latch notch for receiving a pin on the upper ladder portion when the ladder is in the retracted position. In an embodiment, the farm implement also has a dampener with a first end coupled to the lower ladder portion and a second end coupled to the upper ladder portion, the dampener configured to prevent the lower ladder portion from dropping in a rapid and uncontrolled manner. In an embodiment, the dampener is configured to provide a lifting force to assist in returning the lower ladder portion to the retracted position. In an embodiment, the dampener includes a gas spring.
A ladder for a farm implement includes a plurality of retractable components that are linked together to fold in or out in such a manner that the movement of one retractable component can result in the movement of other retractable components, simultaneously. As such, the improved ladder can be folded in or out, i.e., retracted or extended, in one smooth seamless motion as further described in the following examples in
For purposes of illustration, ladder 200 is shown mounted vertically on a right side of farm implement 100 in longitudinal alignment with wheels 105; however, it will be appreciated that the ladder may be mounted forwardly or rearwardly of the wheels. It will also be appreciated that the ladder 200 may be mounted on the right or left side of the implement 100, along a front or rear side of the container, or at a corner of the container.
Ladder 200 includes an upper ladder portion 202 and a lower ladder portion or extension 204. Upper ladder portion 202 has an upper end pivotally connected to container 101 and a lower end pivotally connected to lower ladder portion 204. In an embodiment, upper ladder portion 202 may pivot between a retracted position close to the container 101 (e.g., as shown in
Referring still to
In an embodiment, upper ladder portion 202 includes a pivoting step 214 defining a lower rung of the upper ladder portion, and pivot links 212 are connected to the upper ladder portion via the pivoting step. Pivoting step 214 may be pivotally coupled to upper ladder portion 202 at one end and to pivot links 212 at an opposite end so that it is movable between a retracted position (e.g., as shown in
Lower ladder portion 204 has a first end pivotally connected to a lower end of upper ladder portion 202. A second end of lower ladder portion 204 is free to pivot about the lower end of the upper ladder portion 202 between a retracted position (e.g., as shown in
In the partially extended position shown in
In the fully extended position, the upper ladder portion 202 extends outwardly and downwardly at an angle (e.g., 20°) relative to vertical and lower ladder portion 204 extends from upper ladder portion 202 at the same angle as the upper ladder portion. In an embodiment, the lower pivot links 212 extend upwardly from the frame 103 of the implement 100 to the pivoting step 214 at a second angle (e.g., 30°) relative to horizontal that is smaller than the first angle. In an embodiment, the second or lower end of the lower ladder portion 204 is positioned close enough to the ground in the extended position to allow a user to easily mount the ladder. In an embodiment, the length and angular orientation of the ladder in the extended position is such that the lower ladder portion 204 extends laterally outwardly beyond a reference plane aligned with the right side wall 109 of the container 101.
In an embodiment, the upper end of upper ladder portion 202 is pivotally connected to a bracket 206 configured to be mounted on a container or other surface of the implement (e.g., the bracket 206 may be mounted on a right side wall 109 of the container 101 near a top of the container as shown in
Referring again to
Referring still to
In an embodiment, lower ladder portion 204 includes a pair of parallel uprights 228 (e.g., comprising c-shaped channel members) and a plurality of rungs 230 disposed transversely between the uprights at spaced intervals. The uprights 228 are pivotally connected to the uprights 222 at pivots 226 that define a lower axis of rotation about which the lower ladder portion may pivot. In an embodiment, the lower axis of rotation is parallel to and below the axis of rotation of the pivoting step. In an embodiment, uprights 222 are received within a channel defined by uprights 228, and notches 232 are formed in the channel walls so that rungs 224 in the upper ladder portion 202 are received in the notches 232 when the lower ladder portion 204 is folded upwardly against the upper ladder portion 202 in the retracted position (e.g., as shown in
As best seen in
Referring still to
As best seen in
In use, to extend the lower ladder portion 204, the latch mechanism 238 is released, and the lower ladder portion begins to pivot about pivot 226. This moves the short link 215 so as to cause the pivoting step 214 to pivot about pivot 216. As this step 214 pivots down, it pushes through pivot 218 and the lower pivot link 212 to push the ladder 200 away from the farm implement (as the ladder pivots about pivot 208). Once the lower ladder portion 204 is completely lowered, pivot point 218 is over-centerline of points 216 and 220 to create an over-center latch to hold the lower portion of the ladder away from the farm implement. The dampener 246 helps prevent the lower ladder portion from dropping too quickly. The reverse operation folds the ladder 200 back up for transport; and, if the dampener includes a spring or other elements to provide a lifting force, raising the lower ladder portion upwardly from the extended position to the retracted position may be assisted by the dampener to reduce the amount of lifting force that a user needs to exert.
It will be appreciated that ladder 200 can be made out of any suitable material, such as a metal material, wood material, plastic-based material, fiberglass material, and/or a combination of different materials. Furthermore, the rungs of ladder 200 may have a pattern or grooves that allow for additional grip between a climber's shoe and the rung. While the term “rung” is used, it will be appreciated that such term is meant to encompass any type of step, bar, crossbar, or any other feature that can be used by a user to move up and down a ladder. In a preferred embodiment, one or more of the pivots may include a bushing, such as a nylon or metal bushing, to enhance smoothness of operation.
It will also be appreciated that the embodiments described herein are illustrative only, and that various modifications and changes can be made without departing from the invention. For example, the ladder can be located on other parts of the implement, such as the front, sides, or rear of the implement. Also, more than one ladder can be provided on a farm implement. The upper ladder portion can extend to the top of the implement or terminate below the top of the implement. Also, the movement of the upper and lower ladder portions may be decoupled so that they can be extended and retracted independently of one another. Moreover, while the ladder is particularly advantageous when used on farm implements, it may be used on other types of equipment. While a single mounting bracket is shown for pivotally connecting the upper end of the ladder to a container, it will be appreciated that more than one bracket can be used. It will also be appreciated that, while two pivot links are shown for connecting a lower end of the upper ladder portion to the implement, fewer or more than two pivot links can be used. Furthermore, while the lower end of the upper ladder portion is shown connecting to the frame of the implement via pivot links, it will be appreciated that the lower end can be connected to the container or some other portion of the implement via one or more pivot links. Also, while gas springs are disclosed for dampening downward movement of the lower ladder portion and providing a lifting force to assist in retracting the lower ladder portion, it will be appreciated that other types of dampening devices may be used. For example, various types of pneumatic, hydraulic, and electromechanical dampeners can be used. Preferably, such dampening devices include springs or other types of elements to provide a lifting force to assist in retracting the lower ladder portion. These and other modifications and changes are intended to be within the scope of the invention. CLAIMS
This application claims priority to U.S. Provisional Patent Application Ser. No. 62/110,688, filed on Feb. 2, 2015, the disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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62110688 | Feb 2015 | US |