Not Applicable
Not Applicable
1. Field of Invention
This invention relates in general to bolt cutters but may also apply to other devices for cutting or punching.
2. Prior Art
A commonly used conventional device for cutting bolts, locks, and reinforcement bar is referred to as a bolt cutter. The standard bolt cutter is generally made up of two long handles connected to a pair of opposing jaws that can be manually separated or brought together by movement of the handles. The long handles enable the user to produce force at the jaws for cutting, usually smaller sized bolts. This embodiment relates to a bolt cutter, type cutting tool, specifically with an improved closing mechanism.
Originally bolt cutters were manufactured with relatively long handles to help the user generate the desired cutting force, as with U.S. Pat. No. 3,949,473 to Blanc (1976). However, many consumers are still unable to generate enough force to produce the desired cut. Thereafter, several other cutting tools have been proposed U.S. Pat. No. 5,862,597 to Juros (1999) discloses a cutter with an increased handle arc range that only slightly increased the mechanical advantage upon closing. U.S. Pat. No. 5,014,432 to Putsch (1991) discloses a handle arrangement that crosses over without joint increasing the cutting output, but still requiring the user to generate a substantial amount of force.
U.S. Pat. No. 5,898,998 to Deville (1999) discloses a cutting tool with emphasis on decreasing the thickness of the support members, producing a lighter tool but with still the cutting difficulties of previous cutters.
One of the disadvantages to the existing devices is that the handles have to be made extremely long and it is still difficult for the user to be able to produce sufficient cutting force. It is an object of the present invention to increase by simple means the cutting power produced while closing the more compact handles.
Also, existing devices are limited in their use to the force that can be applied directly by the user of the device. And so the amount of force generated for cutting is limited by the physical strength of the user. Further, the state of the art bolt cutters are heavy and cumbersome to use.
Accordingly, it is an object of the present invention to provide an improved bolt cutter with greater cutting force utilizing a substantially enhanced mechanical advantage thereto. So that cutting of relatively large hard work-pieces, such as bolts or reinforcing bars of steel can be effected with relative ease.
Still another object of the present invention is to provide a bolt cutter, that can be manufactured with a lighter, smaller more compact construction.
The foregoing and other objects, features and advantages of the present invention can be realized by providing a cutting or punching apparatus having at one end a set of jaws and at the other end a relatively shorter length handles that are connected by a means for providing a mechanical advantage. In the disclosed embodiment herein this means includes a threaded rod that can be turned to close the handles and similarly close the jaws.
Numerous other objects, features and advantages of the present invention should now become apparent upon a reading of the following detailed description taken in conjunction with the accompanying drawings, in which:
Reference is now made to the drawings illustrating one possible embodiment of the cutting tool of the present invention. As indicated previously, this tool can be used for cutting such as the cutting of bolts or can be used for cutting cables, locks, reinforcement bar or can even be used for a punching operation. The device is basically comprised of a set of jaws 10 including separate jaws 10A and 10B. Each of these jaws has a cutting blade and is supported for pivotal operation from the handles 12A and 12B. The basic cutting blades and handles 12A and 12B are like that found in existing instruments except that handles 12A and 12B are quite short in comparison to the conventional bolt cutter. When handles 12A and 12B are in a more open position such as shown in
At the base of handles 12A and 12B there is provided a tightening, lead or threaded rod 14 that functions similar to a jack for drawing handles 12A and 12B together such as illustrated by the arrows 15 in
Rotatable handle 16 is secured at the yoke 18 such as by means of pin 20 which may be a cotter pin. The combination of handle 16 and threaded rod 14 associated with handles 12A and 12B provides a substantial mechanical advantage in closing jaws 10 such as from the position shown in
The drawings also show a holder 25 that may be screwed into one of the handles such as into illustrated handle 12A. Holder 25 is preferably engageable on either side of handle 12A or may be engageable with handle 12B depending upon whether the instrument is being held by a left or right handed person. Holder 25 assists in holding and stabilizing the instrument during operation.
As indicated previously, rotation handle 16 may be removed by removing cotter pin 20. This enables one to operate threaded rod 14 in other manners. For example, there may be provided a hex head 28 and if yoke 18 is removed then hex head 28 can be used with a socket, wrench or ratchet to rotate threaded rod 14A. Also, at either end of threaded rod 14 or 14A there may be provided a means for receiving a drive drill or other motorized drive apparatus for driving threaded rod 14 under operator control.
The means provided which includes either threaded rod 14 or 14A for closing handles 12A and 12B of the instrument provides a substantial mechanical advantage over an operator manually operating handles 12A and 12B. This can provide at least one order of magnitude of force greater than is able to be applied by merely manually closing the handles directly. This arrangement, by shortening the length of handles 12A and 12B, also provides a far more compact and easily operable bolt cutting arrangement.
As indicated previously, the distal end of the instrument may also be constructed in different manners. Refer to
Having now described a limited number of embodiments of the present invention, it should be apparent that numerous other embodiments and modifications thereof are contemplated as falling within the scope of the present invention. For example, mention has been made of the use of a motorized drive for threaded rod 14 or 14A. This motorized drive may be provided at either end of threaded rod 14 or the center of threaded rod 14A. Also, other forms of drive members may be engaged with threaded rod 14 or 14A in addition to the use of hex head 28.
The bolt cutter comprises left and right cutting jaws 10 that are closed by handles 12A and 12B. As handles 12A and 12B are separated, the jaws open to allow the material to be cut to enter. As handles 12A and 12B are closed utilizing threaded rod 14 or 14A to draw them closed, the cutting edges of jaws 10 close and cut the inserted material. The improved mechanical advantage provided by threaded rod 14 or 14A allows any user to generate the needed cutting force. Thus, the tool is not limited by the physical strength of the user. The substantially enhanced mechanical advantage allows for the cutting or punching of relatively large hard workpieces, such as bolts or reinforcing bars of steel with relative ease.
Another advantage of the embodiment is a bolt cutter that is less cumbersome and can be manufactured with a much more compact construction than the traditional bolt cutters.
Additional embodiments are shown in
From the description above, a number of advantages of some embodiments of my compact bolt cutter become evident:
Accordingly, the reader will see that the bolt cutter of the various embodiments is much less cumbersome and easier to use than any of the traditional bolt cutters. The cutting force generated by the enhanced mechanical advantage makes it more widely usable, as it is not limited by the physical strength of the user. The relative ease and speed in which it cuts makes it a valuable tool to commercial institutions, fire and rescue teams. Its simplistic design can be easily manufactured and adds a new dimension to the bolt cutting market.
Although the description above contains many specificities, these should not be construed as limiting the scope of the embodiment but as merely providing illustrations of some of the presently preferred embodiments.
Thus the scope of the embodiment should be determined by the appended claims and their legal equivalents, rather than by the examples given.
This application claims the benefit of provisional application Ser. No. 60/879,485, filed 2007 Jan. 9 by the present inventor.
Number | Name | Date | Kind |
---|---|---|---|
492931 | Baird | Mar 1893 | A |
500184 | Beers | Jun 1893 | A |
1592017 | Campen | Jul 1926 | A |
1882218 | Harvey | Oct 1932 | A |
2398209 | Clemens | Apr 1946 | A |
2939211 | Daniels | Jun 1960 | A |
2956340 | Levenson | Oct 1960 | A |
3138869 | Parhaniemi | Jun 1964 | A |
3949473 | Blanc | Apr 1976 | A |
4069582 | Kearns | Jan 1978 | A |
4868986 | Olson et al. | Sep 1989 | A |
5014432 | Putsch | May 1991 | A |
5862597 | Juros | Jan 1999 | A |
5898998 | Deville | May 1999 | A |
6971179 | Erbrick | Dec 2005 | B2 |
7621052 | Kerr | Nov 2009 | B1 |
7690119 | Weber | Apr 2010 | B1 |
Number | Date | Country | |
---|---|---|---|
20080163494 A1 | Jul 2008 | US |
Number | Date | Country | |
---|---|---|---|
60879485 | Jan 2007 | US |