1. Field of the Invention
The present invention relates to hooks that terminate the end of tie down straps and, more specifically, to a hook that includes a magnetic portion.
2. Description of the Related Art
Conventional grab hooks have been available in their present form for many decades and are currently available in a variety of sizes and connector configurations. Grab hooks are typically connected to heavy duty chains that are used to secure, lift, or move heavy loads. The specification refers to the use of such hooks with chains. However, “chain” may refer to any type of securement including but not limited to chains, cables, ropes, straps, and wires, etc. Often, one person uses such chains for these purposes. Because of the strength and durability requirements for such jobs, grab hooks are typically cast or forged with high-strength steel alloys that are ferromagnetic or austenitic. Chains are typically made of a ferromagnetic material.
Typically, the proximal end of the grab hook is attached to the distal end link in a chain, often with a clevis and pin type connection. The distal end of a grab hook has an elongated slot-shaped throat that is sized to accommodate any intermediate link in the attached chain without permitting the either of the adjacent links in the chain to slide through the throat of the hook. Therefore, once the open end of a grab hook is engaged with a chain, the chain will not slide in the hook.
However, the slot-shaped opening in a typical grab hook remains open and will permit an engaged link of a chain to fall out of the hook. The chain is particularly susceptible to falling out of the grab hook before tension is applied to the chain or if tension in the chain is released. This leads to a particularly difficult problem when one person is using the chain because the first end of the chain falls off the hook before the other end is secured causing the user to have to reattach the first end and hope that it stays in place. One solution is for the user of the chain to get assistance from a helper who holds the grab hook in place while the user applies tension to the chain. Another solution that is sometimes used when a helper is not available is for the user of the chain to tie a knot in the chain rather than using the hook. This approach is not preferred and sometimes even dangerous because knots in chains are notoriously unreliable when high tension loads are applied to the chain. Commercial users of chains straps or cables, e.g., truckers, loggers and construction workers need grab hooks that will stay in place on the chain or cable until tension can be applied to the chain, strap or cable.
To address this problem in the past, grab hooks have been fitted with latches to dose the open end after the grab hook engages the chain. One such grab hook is described, for example, in U.S. Pat. No. 6,019,408. Such latches are sometimes spring loaded and come in a wide variety of configurations. However, latch mechanisms add complexity to the grab hook which can require additional steps to engage the grab hook with the chain. Some of such latches can be difficult to open and dose, especially when the user is wearing protective gloves. Such latches may also break during use, at least rendering the latch inoperative and perhaps interfering with the normal use of the grab hook itself.
Tie-down straps are commonly used for securing objects being transported to the vehicles transporting them. Typical tie-down straps include a nylon web belt in which each end terminates in a hook for securing the belt to the vehicle. A ratcheting mechanism may be used to tighten the strap. Frequently, users of tie-down straps become frustrated while securing the straps to the connection points on vehicles because one end often gets pulled away from a connection point when the user is trying to secure the other end to a different connection point.
Therefore, there is a need for a tie-down strap with a hook that tends to stay in place prior to the final securing of the tie-down strap.
The grab hooks described in this document include a magnetic portion near the distal end of the hook that is positioned to magnetically engage at least one link in a chain when another link of the chain is positioned in the throat of the hook. The magnetic connection between the grab hook and the chain prevents the chain from falling out of the throat while the chain is slack. The magnetic connection thus permits the user of the chain to position the other end of the slack chain and apply tension to the chain to secure the chain in its operative position, for example, for securing, towing, or lifting a load. The grab hook described has no latches or other moving parts for securing the slack chain in the throat of the grab hook, Therefore, the described grab hook is simpler to operate than conventional grab hooks with latches to dose the throat.
The disadvantages of the prior art are overcome by the present invention which, in one aspect, is a tie-down strap that includes a web belt having a first end. A hook is coupled to the web belt at the first end. A first magnet is embedded in the hook.
In another aspect, the invention is a hook for use with a tie-down strap that includes a shank portion that terminates in an eye and a bend portion. A bite portion extends from the bend portion. A first magnet is embedded in a selected one of the shank portion and the bite portion.
These and other aspects of the invention will become apparent from the following description of the preferred embodiments taken in conjunction with the following drawings. As would be obvious to one skilled in the art, many variations and modifications of the invention may be effected without departing from the spirit and scope of the novel concepts of the disclosure.
A preferred embodiment of the invention is now described in detail. Referring to the drawings, like numbers indicate like parts throughout the views. Unless otherwise specifically indicated in the disclosure that follows, the drawings are not necessarily drawn to scale. As used in the description herein and throughout the claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise: the meaning of “a,” “an,” and “the” includes plural reference, the meaning of “in” includes “in” and “on.”
As shown in
FIGS. 3 and 5-7 illustrate details of grab hook 10 with an integrated magnet 12, a chain 40 that is compatible with grab hook 10, and a clevis pin 16 used to secure grab hook 10 to distal link 48 in chain 40. Clevis 18 includes bores 19 that are sized to accept clevis pin 16. The space in clevis 18 is sized to accept the end of link 48. Once link 48 is positioned in the opening of clevis 18, clevis pin 16 is inserted through bores 19 and the interior opening of link 48. Cotter pin 17 secures clevis pin 16 in this position so that grab hook 10 is securely fastened to link 48. The distal portion of grab hook 10 is extended distally as compared to conventionally shaped grab hooks to add strength to grab hook 10 despite the presence of bore 14. Magnet 12 is illustrated as a cylindrical magnet that is sized to form an interference fit inside bore 14 in the distal portion of grab hook 10.
As shown in
It will be apparent to those skilled in the art that various modifications and variations can be made in the grab hook of the present invention and in the construction of the grab hook without departing from the scope or spirit of the invention. For example, the grab hook 10 has been described in connection with chain 40. However, any hook with a magnet positioned in the distal portion of the hook combined with any type of long securement such as a cable, rope, or strap with a ferrous portion capable of engaging with the magnet in the hook can exhibit the advantages of the exemplary combinations of hooks and chains described above.
As shown in
One or more magnets (such as rare earth magnets) can be embedded in the hook 110. For example, a first magnet 116 can be embedded in the shank portion 110 and a second magnet 118 can be embedded in the bite portion. Typically, the magnets 114 and 116 are press fit into holes drilled in the hook 110. The magnets 116 and 118 can be used to hold the hook 110 against ferrous surfaces 102 when the tie down strap 100 is being placed prior to its being secured.
The above described embodiments, while including the preferred embodiment and the best mode of the invention known to the inventor at the time of filing, are given as illustrative examples only. It will be readily appreciated that many deviations may be made from the specific embodiments disclosed in this specification without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is to be determined by the claims below rather than being limited to the specifically described embodiments above.
This application is a continuation-in-part of, and claims the benefit of, U.S. patent application Ser. No. 13/571,894, filed Aug. 10, 2012, which is a continuation-in-part of, and claims the benefit of U.S. patent application Ser. No. 13/135,367 filed Jul. 2, 2011, now abandoned, the entirety of each of which is hereby incorporated herein by reference.
Number | Date | Country | |
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Parent | 13571894 | Aug 2012 | US |
Child | 13961331 | US | |
Parent | 13135367 | Jul 2011 | US |
Child | 13571894 | US |