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Publication numberUS2678578 A
Publication typeGrant
Publication dateMay 18, 1954
Filing dateAug 30, 1951
Priority dateAug 30, 1951
Publication numberUS 2678578 A, US 2678578A, US-A-2678578, US2678578 A, US2678578A
InventorsJoseph L Bonanno
Original AssigneeJoseph L Bonanno
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Magnetizable hand tool
US 2678578 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

May 18, 4 J. L.-BONANNO MAGNETIZABLE HAND TOOL Filed Aug. 30, l95l All llllllllllllll lillli IIIII ll. lllll .IIIII lll ll Ililllllllu I N V EN TOR. f/ZSEPH L. 25am NA/O. BY

llll IIIIIIIU; Illllllliillll'llilllllliilllllI Patented May 18, 1954 UNITED STATES PATENT OFFICE 2,678,578

MAGNETIZABLE HAND TOOL Joseph L. Bonanno, Madison, N. J. Application August 30, 1951, Serial No. 244,349

6 Claims.

The present invention relates to magnetizable hand tools and more particularly to hand tools suitable for use either magnetized or nonmagnetized.

The present invention contemplates hand tools such as wrenches and screwdrivers having work engaging tips or ends adapted to cooperate with the magnetizable work piece, such as a screw, a nut or a bolt head, and provided with a permanent magnet which can be brought into position to magnetize the tip so that it then acts as a keeper, or shifted to another position, where upon the magnetized tip loses its magnetism, and the permanent magnet is retained there.

It is thus possible to use the screwdriver, wrench or similar article as an ordinary nonmagnetized tool or as a magnetized tool, as desired.

According to the present invention the shank of the tool is made of non-magnetizable tubular material, such as stainless steel, and is connected at its end or ends to a suitable tip for the work intended. At the end of the non-magne tizable tube remote from the magnetizable tip there is a second magnetizable keeper adapted to retain the permanent magnet against it. Where the tool has two working ends each may be magnetizable.

Other and further objectswill appear as the description proceeds.

The accompanying drawings show, for purposes of illustrating the present invention, several embodiments in which the invention may take form, it being understood that the drawings are illustrative of the invention rather than limiting the same.

In these drawings:

Figure 1 is an exploded perspective view illustrating a screwdriver in which the present invention is embodied;

Figure 2 is a sectional View of the screwdriver assembled and showing the magnet in position to magnetize the screwdriver bit;

Figure 3 is a view similar to Figure 2 showing the magnet in position to demagnetize the tip;

Figure 4 is an elevational view illustrating the manipulation employed when the permanent magnet is to be shifted toward the work engaging tip;

Figure 5 is a similar view illustrating the shifting of the magnet away from the same;

Figure 6 is a fragmentary sectional view illustrating the use of a magnetizable tip in the form of a wrench socket;

Figure 7 is a fragmentary view illustrating the magnetizable tip in the form of a box wrench; and

Figure 8 is an elevational view on a small scale illustrating the tool adapted for use as both a wrench and screwdriver.

As shown in Figs. 1 to 5, the screwdriver is of conventional appearance. It has a hard steel magnetizable tip or bit 50, reduced at the end as indicated at H to fit the slot of a screw S, and received in the lower end of a nonmagnetizable metal tube l2, preferably stainless steel. The parts It and it are brased together. The upper end of the tube i2 receives a soft iron insert I 3 which is held in place in any suitable manner. The tube 62 also receives a magnet l4 permanently magnetized lengthwise, as indicated. The upper end of the handle as shown in Figs. 1 and 3 receives a handle [5 which may be secured to it in any suitable manner, as for example, by knurling on the tube H2. The length of the tube I2 is such that some free space is provided between the permanent magnet l4 and the magnetizable members II and [3 so that when the magnet is in contact with one of the magnetizable members there is an air gap between it and the other magnetizable member.

The permanent magnet M has suflicient mass relative to the attractive force it exerts on the keepers It] or it so that it can be dislodged from whichever keeper it is in contact with and shifted to the other keeper. If one wishes to have the tip 10 magnetized, such a condition may be assured by grasping the screwdriver as illustrated in Fig. 4 and bringing the tip down against some relatively fixed stop so that the movement of the entire screwdriver is suddenly interrupted. This will have imparted sumcient inertia to the magnet so that it will break away from the upper keeper [3 and slide down the tube to the lower keeper or tip and will then adhere to and magnetize it.

If, on the other hand, one desires to be sure that the tool does not have a magnetized tip, the screwdriver is grasped as indicated in Fig. 5 and the handle of the screwdriver brought against an object with sufiicient force to cause the magnet to separate from the magnetized tip I 0.. It then passes down the tube and adheres to the keeper I3 in the handle end of the screwdriver. The operation of shifting the magnet the entire length of a long tube is facilitated by gravity when the tube is brought down against the abutment or stop. When the tube is short, suflicient inertia can be imparted to the magnet to separate it from one keeper and bring it against the other.

Figure 6 illustrates a modification in which the protruding keeper 20 has a downwardly opening socket 2| adapted to fit nut N. When a magon one end has a screwdriver bit it! and the other a wrench head such as 20. Here the permanent magnet l4 travels from one end of the tube 30 to the other and each of the keepers is shaped to cooperate with the work piece, screw or nut.

Since it is obvious that the invention may be embodied in other forms and constructions within...

the scope of the claims, I wish it to be.understood that the particular form shown is but one of these forms, and various modifications .andchangesbe-a ing possible, I do not otherwise limit myself in any way with respect thereto.

What is claimed is:

1. .A handtoolusable as a magnetized tool or, as

a nonma'gnetized tool; comprising a nonmagnetic W shank including a hollow tube, two tube-carried,v

magnetizable .keeperswhich with the. tube .forrn closed: at the..ends,-. one. keeper :protrudingand shaped '.to cooperate with a work-piece, and a permanent .magnetinthe space between thekeeperszand shorter than .said

space, the ;magnet'. being gcontactable with one keeper onlyat a-time toamagnetize it and having sufiicient mass to acquire, in response toa sudden. jolt inadirection opposite .theiorce of. magnetic. attraction, an inertia sufficienttodislodge it from. the magnetized keeper. so that the keeper loses.

its..magnetismandthe magnet may move freely in the-,tube-andwhen brought. adj acent. the other.

keeper magnetize the.. same andbe held in position thereby.

2'. A screwdriver usable as a magnetized screwdriver or as a nonmagnetizedscrewdriver, comprising a. nomnagnetic shank: including .ahollow tube, two tube-carried, magnetizable. keepers: which with the-tube forman. elongated chamber.

closed-at the. ends; one keeperi.;protruding and shaped toform a screwdriverbitto cooperate with .a .work :piece, a permanent. magnet. in the. space between'the; keepers andshorter than said space, the magnet, being; contactable'. with one keeper-only at a time tomagnetize; it ;and.having suiiicient mass .to acquire, in responsetoia sudden. jolt in a direction opposite the force"of.'magnetic.;- attraction, an inertia sufiicient to'dislodge it from the.-magnetized keeper so thatcthe keeper. loses its magnetism and themagnetmayamove freely in the tube andwhen-broughtadjacenttheother.

keepenmagnetize the. sameqand' be held in posi:- tion thereby, and a handle securedto the shank;

3. A wrench usable as .amagnetized wrench. or as a nonmagnetized wrench, comprising :a nonmagnetic shank including a hollow tube, two

tube-carried,- magnetizable keepers ...which; with the tube form an elongated. chamberzolosed at the ends, one keeper protruding .andishapedato .form'...

a wrench head to cooperate with a work piecaa permanent magnet 1 in the space betweerr; the;

keepers and shorter than said space, the magnet being oontactable with one keeper only at a time to magnetize it and having sufiicient mass to acquire, in response to a sudden jolt in a direction opposite the force of magnetic attraction, an inertia sufficient to dislodge it from the magnetized keeper so that the keeper loses its magnetism and the magnet may move freely in the tube and when brought adjacent the other keeper magnetize the samerand be held in position thereby, and a handle secured to the shank.

4:. A hand tool usable as a magnetized tool or asa nonmagnetized tool and comprising, a stainless:-.steel,itubular, manually rotatable shank, a magnetizable tool head fixedly secured at one endof the'shank and closing ofi that end of the shank-,..aamagnetizable keeper spaced from the tool head and closing off the shank to form an elongated space, a handle carried by the shank, and a permanent magnetirin the space between the.magnetizableeelements iand.shorter: than said space; thetmagnet :being; contactable. with: one-a1 suchuelement;onlylat a .time .to: magnetize it -.:and:; having sufficient mass to acquire, in; a -.sudden':jolt.;in-. a..dir.ection...opposite ..the .force oilmagnetic:attractionpan inertia sufficient toe; dislodge it rfrom: the .magnetizedelement soithat; it ..loses .-,-its: magnetism-1' and"; the; magnet may; move.:freely :inzthe; tube.. and:.;when. broughtzad-zr jacent= the. other: magnetizable- .elementr. mag-y netize;held:in; position: therebyz'.

5...A .screwdriverihaving a magnetizablescrewsdriver 1-bit; a, tube of. nonmagnetizable 1111613311. into: the end of .whichthe bitzis nonrotatablysecured;., a magnetizable plug: carriedin: theizother end of the tube; handles securedato';the1-tubev and: a2: permanent::magnet1shorter: zptl'ianuzthev spacingof the..magnetizab1eLparts ;and;movable in the-tube between themagnetizable .parts, theimagnetvhava ing; insufficient adherence to the .2 magnetizablepart'with WhlClI'it lSziIl contactztorholditltherea when the screwdriverv "is :subjected .to ads-sudden; joltxtending; to': dislodge the: magnet;

6. *A 1..wrench zhaving. a magnetizable z-WI'BDLOhIT head, a. .tubersof nonmagnetizableametal 111110713118 end. of whichctheiwrench head.- is nonrotatably'." secured, a magnetizable plug carriedJinLthe:other; end; of 2. the .':-tube, L a': handle secured .to s the: tube and a permanent magnet shorter; than ....the:..: spacing of: theimagnetizable partsrandwxmovable in the tubebetween "the magnetizableiparts; the

magnet having .insufiicientadherencetether-mag: netizable apartzwith which it'is iILCOIItaCtLtOIhOIdXJ it there c-when;..the.: wrench .is subjected. to a sudden jolt tending to dislodge: the-magnet: f'

References -.=Cited-"ini.thez fil;.-of this: patents. UNITED STATES PATENTS-

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US512381 *Apr 12, 1893Jan 9, 1894 James t
US2260055 *Sep 19, 1939Oct 21, 1941Gen ElectricMagnetic tool
US2417762 *Apr 14, 1944Mar 18, 1947Koller StevenTool for magnetic lifting
US2550775 *Jul 13, 1949May 1, 1951Wade StevensonMagnetic screw driver
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2714829 *Oct 6, 1954Aug 9, 1955Wade StevensonMagnetic wrench having its magnet inwardly spaced from its nutengaging socket by a hollow magnetic sleeve
US2806396 *May 6, 1954Sep 17, 1957George M MillerPermanent magnet for use with socket wrenches, conveyor belts, extension tubes, and the like
US2813511 *Jul 5, 1955Nov 19, 1957Parker Pen CoWriting instrument
US2870741 *Jul 5, 1955Jan 27, 1959Parker Pen CoWriting instrument
US3327516 *Jul 22, 1964Jun 27, 1967Carroll W HoshourPercussion tool holder
US4238163 *Sep 14, 1978Dec 9, 1980Hung Kuo HuaMagnetic writing implement
US4878406 *Sep 28, 1988Nov 7, 1989Sk Hand Tool Corp.Screwdriver blade
US5090276 *May 17, 1991Feb 25, 1992Groskey Richard EWrench for installing strainer base in sink
US5461944 *Jun 17, 1994Oct 31, 1995Ciumaga; MassimoMethod of making a screwdriver
US6026717 *Jul 23, 1998Feb 22, 2000Anderson; WayneDriver tool with high energy magnetizer/demagnetizer on tool handle
US6026718 *Sep 28, 1998Feb 22, 2000Anderson; WayneHigh energy magnetizer and selective demagnetizer integral with driver tool or the like
US6032557 *Sep 1, 1998Mar 7, 2000Anderson; WayneDriver tool kit with high energy magnetizer/demagnetizer on tool handle(s)
US6060801 *Sep 28, 1998May 9, 2000Anderson; WayneHigh energy magnetizer/demagnetizer for drill housing
US7247780 *Apr 1, 2005Jul 24, 2007Sanders Peter JWrench tremolo bar for a guitar
US7618435 *Nov 17, 2009Nmt Medical, Inc.Magnetic attachment systems
US7981116 *Jul 19, 2011Custom Spine, Inc.Radiolucent screwdriver for orthopedic surgery
US20040176797 *Mar 4, 2003Sep 9, 2004Nmt Medical, Inc.Magnetic attachment systems
US20060219086 *Apr 1, 2005Oct 5, 2006Sanders Peter JWrench tremolo bar for a guitar
US20080294173 *May 25, 2007Nov 27, 2008Reeder Jr Ralph FRadiolucent screwdriver for orthopedic surgery
US20090041554 *Aug 8, 2007Feb 12, 2009Hsu Hsiu-Kwei LiuChamfer drill
US20110191979 *Aug 11, 2011Boren Dane AMethods of Using Cutting Devices for Printing, Devices for Performing the Same, and Systems including such Devices
USRE36797 *Jul 2, 1998Aug 1, 2000Snap-On Technologies, Inc.Magnetic bit holder and hand tool incorporating same
USRE38778Jul 2, 1998Aug 23, 2005Snap-On IncorporatedMagnetic bit holder and hand tool incorporating same
U.S. Classification81/436, 7/901, 81/125, 401/100, 401/115
International ClassificationB25B23/12
Cooperative ClassificationB25B23/12, Y10S7/901
European ClassificationB25B23/12