Embodiments of the present invention relate to the field of retractable support cranks, sometimes referred to as landing gear cranks, which may be typically found on tractor trailers and other large machines, and specifically pertain to an improved hand crank for raising and lowering landing gear by accommodating both high leverage and high-speed cranking operations.
Current hand cranks are usually of a single piece with a single handgrip to facilitate the cranking operation. The crank must have a large enough offset from the crank axis of rotation or centerline to enable an operator to be able to lift a loaded trailer. These existing designs are a compromise between being too long to turn rapidly and too short to exert maximum leverage. Whether the required cranking effort is high or low, the single larger offset requires the operator to bend up and down while turning the crank, stressing the back and shoulders and causing excessive fatigue.
Lowering the landing gear requires little effort as its weight aids the process. Turning the long crank is inefficient so many drivers will get the crank spinning rapidly with one finger in the middle of the offset arm. This is very dangerous, as their arm is in the middle of the spinning grip and many drivers have been hit and seriously injured.
While some cranks may have multiple handles, or may have two or more handle positions, they require cumbersome multi-part jaw connections that allow for the crank to be moved from one position to another position.
Embodiments of the present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings. To facilitate this description, like reference numerals designate like structural elements. Embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings.
In the following detailed description, reference is made to the accompanying drawings which form a part hereof wherein like numerals designate like parts throughout, and in which is shown by way of illustration embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of embodiments in accordance with the present invention is defined by the appended claims and their equivalents.
The following description may include terms such as inner, outer, under, between, upward, downward, outward, inward, and the like, which are used for descriptive purposes only and are not to be construed as limiting. That is, these terms are terms that are relative only to a point of reference and are not meant to be interpreted as limitations but are, instead, included in the following description to facilitate understanding of the various aspects of the invention.
The phrase “in one embodiment” may be used repeatedly. The phrase generally does not refer to the same embodiment; however, it may. The terms “comprising,” “having,” and “including” are synonymous, unless the context dictates otherwise.
The phrase “A/B” means “A or B.” The phrase “A and/or B” means “(A), (B), or (A and B).” The phrase “at least one of A, B and C” means “(A), (B), (C), (A and B), (A and C), (B and C) or (A, B and C).” The phrase “(A) B” means “(B) or (A B)”; that is, A is optional.
The terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Rather, in particular embodiments, “connected” may be used to indicate that two or more elements are in direct physical or electrical contact with each other. “Coupled” may mean that two or more elements are in direct physical or electrical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other.
The first handle piece 12 may be adapted to be connected to a driving rod 20, which may be adapted to drive a landing gear raising and lowering mechanism, such as a gear box, hydraulically actuated device, and the like. The crank 10 may be adapted to rotate about an axis 22, which may be coaxial with the driving rod 20, and thus may be adapted to drive the driving rod 20 for rotation. The second handle piece 14 may have a first end 24, for example, a graspable first end, which may include a first hand grip portion 25. Second handle piece 14 may also have a second end 26, which may be adapted to be connected to the first handle piece 12.
When in the first configuration 16, the first end 24 may be an offset or first radial distance 28 from axis 22. When in the second configuration 18 the first end 24 may be a second radial distance 30 from axis 22. The first configuration 16 may be referred to as a high-speed configuration, in that the crank may be rapidly rotated by an operator. Various embodiments of the present invention may include a hand crank having at least two hand gripable portions that may allow an operator to more ergonomically and safely operate the hand crank. In one embodiment, the offset or first radial distance 28 between the first hand grip portion 25 and the axis 22 is substantially the same as the distance between the second hand grip portion and the axis 22. In other embodiments, the offset distances may be different.
Referring again to
In one embodiment one or both of the first hand gripable portion 25 and the second hand gripable portion 32 may make an angle 35/36 with the second connecting member 34 of less than or substantially equal to 90 degrees. Various embodiments may be ergonomically correct in that they may be adapted to keep an operators hands in front and close to the body, and may require larger muscle groups to be utilized to operate, rather that smaller muscle groups. Further, such a configuration necessarily limits the amount of protrusion the hand crank may have from the side of, for example, a tractor trailer. And, the hand gripable portions may be kept closer to the connecting drive shaft, which may enhance stability during the raising and lowering operation, and reduce the bending tendency and wobble that may be encountered if the hand grippable portions were extended at larger angles.
A releasable locking mechanism may be coupled between the first and second handle pieces 12/14, which may allow for the second handle piece 14 to be reoriented relative the first handle piece 12 from the first configuration 16 to the second configuration 18. The releasable locking mechanism may also allow locking of the pieces with respect to each other in a desired position. In one embodiment, the releasable locking mechanism can releasably lock the second handle piece 14 in either a high speed or high leverage position, with respect to the first handle piece 12 and the axis 22 of rotation.
The releasable locking mechanism may include a number of different devices, including, but not limited to button biased connectors, squeeze spring pin connectors, fixed pin connectors, barrel thread connectors, and the like. Embodiments of the present invention may include locking mechanisms that do not require the use of tools in order to facilitate quick and hassle free locking and unlocking.
For example,
In various embodiments, the second handle piece 14 may be adapted to engage the first handle piece in a telescoping manner, such that the second handle piece has an inner diameter that is larger than the outer diameter of the first handle piece. In other embodiments, the first handle piece and the second handle piece may join at a rotatable union that is adapted to allow one handle piece to rotate about the other.
The connection end 60 may also include a straight portion 66 adapted to pivot relative the driving rod in a stored position 68 as illustrated in
The connection end 60 may include a slot 72 disposed therein that extends from the straight portion 66 to the tubular portion 62. The driving rod 20 may include a protrusion 70 that may be adapted to extend into the slot 72, to provide a rotation resistance when the driving rod is being rotated by the first handle piece 12 (operational position), as well as guide the connection end 60 while retracting from an operational position to the stored position, and to provide a pivot about which the first handle piece may pivot.
In one embodiment the second handle piece 114 may be adapted to be pulled against the spring 116 and repositioned to a second configuration 18 such as that illustrated in
Although certain embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent embodiments or implementations calculated to achieve the same purposes may be substituted for the embodiments shown and described without departing from the scope of the present invention. Those with skill in the art will readily appreciate that embodiments in accordance with the present invention may be implemented in a very wide variety of ways. This application is intended to cover any adaptations or variations of the embodiments discussed herein. Therefore, it is manifestly intended that embodiments in accordance with the present invention be limited only by the claims and the equivalents thereof.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/645,943 entitled RETRACTABLE SUPPORT CRANK METHOD AND APPARATUS, filed Jan. 19, 2005, and U.S. Provisional Patent Application Ser. No. 60/667,268 entitled RETRACTABLE SUPPORT CRANK CONNECTOR METHOD AND APPARATUS, filed Mar. 31, 2005.
Number | Date | Country | |
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60645493 | Jan 2005 | US | |
60667268 | Mar 2005 | US |