US2471764A

US2471764A - Magnetic hand pickup tool

Info

Publication number: US2471764A
Application number: US644510A
Authority: US
Inventors: Carl H Miller; Wilbur S Wilks
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-01-31
Filing date: 1946-01-31
Publication date: 1949-05-31
Anticipated expiration: 1966-05-31

Description

y 1949- c. H. MILLER ET AL 6 MAGNETIC HAND PICKUP TOOL Filed Jan. 31, 19,46

FIG. 1

FIG. 2

.FIG. 3

CARL H. MILLER wl s WILKSINVENTORS Patented May 31, 1949 MAGNETIC .HAN D PICKUP .TOOLL '1 can H. Miller, Arlington, Va., and ,Wilbur. .S.--.-

Wilks, Trenton, N. J

Application; J anuary 31, 1946-, SeriabNoi 644510: {2

4 Claims. (or. 294-655) 1 t This invention relates to improvements in hand tools for picking up small objects and- .particularly to .a comparatively smallhand tool including .a permanent magnet for; picking 1 up small objects; of magnetic materiaLsuch as steel screws,

pins ,and, other small. objects, or. mechanical. parts ofl magnetic material.

While devices. for the same general purpose.

havebeen previously propos ed,;they have involved V certain material defects and disadvantages and have, not, sofar as 'we are aware;.met with any appreciable degree of commercial-success.

Among such defects and disadvantages are the complicated and. expensivenatureof some of the previously proposed :devices, .the failure of the design of such devices to. fully-take into consideration the various factors ofl-manual skill involved in: handling. very small objects" by such a device and the failureof such devices toprpvide any means to neutralize the effect of the. permanent magnet .when the, deviceis not. inv use to avoid magnetizing watches -.and. similar. mechanisms which may happen to. be located at times near the pick up tool.

b therefore an objectof .the presentinvem. tion to provide a magnetic hand pick up tool. of

An additional object resides in the provision;

of an improved magnetichand pick up tool which may be conveniently and efficiently operated by one hand, leaving the other hand of the user free and by means of which small objects or machine parts may be handled with the highest degree of skill and dexterity.

Other objects and advantages will become apparent as the description proceeds in connection with the accompanying drawing in which like reference numerals are used to designate similar parts throughout.

In the drawing:

Fig. 1 is a longitudinal sectional view on an enlarged scale of the improved magnetic hand to Fig; 2, a longitudinal:sect-ionalrview of. a fragmentary portion. of the tool shownirr Figal showy, ing; the magnet; in a'different 4 position -from-,thats L illustrated in Figz.;1;;and

Fig, 3, .a longitudinal; elevational :viewof Lathe improved. hand, toolat. .approxi'matelyvthe--fulllii size of .a convenient form of-the tool.;

With; continued,;reference -.to-j the: drawing theniv improveclmagnetic hanpLtool comprisesa tubulamr rod-:or;;handle portions! formed of. a lion-mags:-

neticmaterial and preferably formed; of, a suit-n; able plastic or syntheticyresinnmaterial-tfor ap,-.-- pear;anc e,-- and economyand convenience ofumane llf-EtCtLlIEu: At oneendthereofrthe rodmembertlfl l is tapered, as indicated at [2, andwithirr the .ta-n pered portion is pmyidedwith' an internal radial shoulderM-between which and the adjacent Gilda; of,.the tube-"there is provided a cylindricalape ture l6 of -a diameter somewhatflessthanthatmfiir the ab ore ofthe remainder: ,of the, tube.-

A tubular sleeve 18,. act-magnetic; materialwisn; fitted intojtheborfi. of the tube-:lO-and, bears at one.end= againstthe: shoulden l4 and a :mag-netri; generally indi-oatedat fill-is -slidably. 1 mountedinn; thesleeve. 18.1 Thisama let is :ofthe form comr: monly; referred etc inathe artvas ua .dumbbejll'h typeima net and? "has-enlar ed. end portions 2 22; and 24 joined by a coaxial cylindrical-.intermediiate portion 26 smaller in diameteri-than. the-lend portions, The magnet 20 sis a permanent .type magnetand is preferably-formed of a special allow;- which provides a magnetrofsextremely high at:

tractive force-forthe. weight thereof and of a high degree-ofpermanence.

same length. 1

The magnethas; twoglimiting-positions, name-@ 1- ly the retracted positionshown in Fig.1 1 andtthe -.extended .or .proj egtedapqsition shown :inr-F g 2 When: themagnet is-in itsyretracted positioninm which it lies wholly within the sleeve I8,.as shown. :2

in Fig. 1, its magnetic effect is completely neutralized by the sleeve since the magnetic field between the two end portions of the magnet is then concentrated in the sleeve and does not extend therebeyond. When the magnet is in its projected position as illustrated in Fig. 2, one end pole is disposed beyond the adjacent end of the sleeve and the magnetic field thus no longer flows through the sleeve but must pass through the air in the space between the projected end of the magnet and the adjacent end of the sleeve. Thus when the magnet is in the projected position, as shown in Fig. 2, the tool is operative to The sleeved-l8.oft-magnetic material and-the magnet 20 are. preferably of substantially thew 3 pick up objects of magnetic material of a weight within the capacity of the magnet. When it is desired to release such objects the magnet is retracted and when its magnetic effect becomes neutralized the object will be released.

The magnet is projected by suitable means such as the cylindrical rod 28 which extends through the tubular member l0. At its end adjacent the magnet 26 this rod may be provided with a reduced portion in the end of which is a well 3| surrounded by a thin Wall 32. On the adjacent end of the magnet there is a ball end extension 34 the ball 38 of which is received in the well 3|. The edge of wall 32 is swedged in to lock the ball in the end well of rod 28.

At its end opposite the magnet the rod 28 is provided with an additional reduced portion 38 which extends through an apertured cap 48 screw threaded into the end of tubular member ID. This extension 38 provides an external plunger on the tool which when depressed by a finger of the user projects the magnet beyond the sleeve l8 and the corresponding end of the tubular member I to the position illustrated in Fig. 2.

The magnet is returned to its retracted position by suitable means such as the coiled compression spring 42 interposed between the end of sleeve I 8 opposite the shoulder M and radial shoulder 44 provided on rod 28 surrounding reduced portion 32. When the rod 28 is moved by pressure on the plunger portion 38, the spring 42 is compressed to the condition shown in Fig. 2, and when the pressure on the plunger is released the spring expands to retract the magnet to the position shown in Fig. 1.

As stated above, the entire tool is of approximately the size of a lead pencil, as is shown in the full-size drawing of Fig. 3 and is preferably provided with a clip 46 by means of which it may be retained in the pocket of the user in the same manner as a pencil or fountain pen.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is shown in the drawing and described in the specification but only as indicated in the appended claims.

What is claimed is:

1. In a magnetic hand tool for picking up small objects of magnetic material, a tubular handle member at least a portion of which is composed of non-magnetic material; a sleeve of magnetic material fixed in one end portion of said tubular member; a generally cylindrically shaped magnet slidable in said sleeve between a retracted position in which it is disposed wholly within said sleeve and its magnetic action is neutralized by said sleeve and an extended position in which one end of said magnet is projected beyond said sleeve to an extent such that the neutralizing eifect of said sleeve is discontinued; manually 4 operable means extending through said tubular member for projecting said magnet; and resilient means within said tubular member operative to retract said magnet.

2. In a magnetic hand tool a handle portion; a magnet carried by said handle portion; a sleeve of magnetic material carried by said handle portion surrounding said magnet to neutralize said magnet; and manually operable means carried by said handle portion to project said magnet beyond said sleeve to discontinue the neutralizing eifect of said sleeve on said magnet.

3. In a magnetic hand tool, a tubular member; a magnet carried by said tubular member; a sleeve of magnetic material fixed in said tubular member surrounding said magnet; and means operative to project and retract said magnet and operatively connect it with said tubular member comprising a rod extending through said tubular member to provide a push button for projecting said magnet; and a spring acting on said rod to retract said magnet.

4. In a magnetic hand tool for picking up small objects of magnetic material, a tubular handle member of non-magnetic material, a sleeve of magnetic material fixed in said tubular member adjacent one end thereof, a generally cylindrically shaped magnet having enlarged ends and a reduced intermediate connecting portion slidably received within said sleeve, the inner diameter of said sleeve and the outer diameter of said enlarged ends being such that there is substantially no air gap therebetween, said magnet being movable axially between a retracted position in which it is disposed wholly Within said sleeve whereby the external magnetic flux path is entirely through said sleeve and the magnetic attraction externally of said tool is neutralized and an extended position in which one end of said magnet is projected beyond said sleeve to an extent such that the neutralizing eifect of said sleeve is discontinued, manually operable means extending through said tubular member for projecting said magnet, and resilient means within said tubular member operative to retract said magnet.

CARL H. MILLER.

W. S. WILKS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 432,896 Porter July 22, 1890 512,381 Keyes Jan. 9, 1894 FOREIGN PATENTS Number Country Date 11,952 Great Britain May 13, 1897