US2595683A - Tweezer - Google Patents

Description

May 6, 1952 2,595,683

C. J. LO MONTE TWEEZER Filed NOV. 15, 1948 Wifi i INVENTOR.'

CHA R1. 5S J L o Mo/VTE.

Patented May 6, 1952 UNITED STATES PATENT GFFICE TWEEZER Charles J. Lo Monte, Los Angeles, Calif.

Application November 15, 1948, Serial No. 60,048

2 Claims. l

This invention relates to tweezers and more particularly to a new and improved tweezer normally held in spring-closed tensioned position and preferably provided with adjustable means for regulating the tension to a desired degree.

Tweezers of conventional construction known to the prior art ordinarily are closed by squeezing the arms of the tweezer together for closing the jaws during use. There is no certainty nor accuracy, however, in the manner in which the jaws clamp upon hair or other material due to the uncertainty of the operator as to the amount of force he is exerting especially while moving the instrument. Moreover, various individuals employ more or less force, some sufficiently great to distort the tweezer and throw the jaws out of alignment, thereby rendering the device either permanently useless or ineffectual during the particular operation involved. Manifestly, too great a tension applied too close to the jaws of normal tweezers will cause the jaws to pivot upon their heel portion leaving the operative tip open.

It is desirable that once tweezers are applied to the work. no further force than their withdrawal in a manner to carry out their intended function be necessary. Tweezers of applicants new and improved construction may be adjusted to any desired degree of tension without distorting the clamping edges and thereby retaining their desired alignment. Due to their ability to be pre-tensioned, whether adjustably or permanently. they may be used with equal effectiveness by persons of varying strength and skill.

In addition, the use of a clamping rim of the desired character described permits a maximum of gripping eiect per unit area associated with a minimum force necessary to close them. And by the fact that no force need be applied by the operator to retain tension upon the work once a grip is secured. greater delicacy, accuracy and effectiveness of operation is developed.

It is therefore an object of this invention to provide a new and improved tweezer pre-tensioned for closing.

It is another object of this invention to provide a tweezer having an adjustable means for establishing the closing tension.

It is another object of this invention to provide Vtweezers of the desired character described including means for retaining the operative surfaces in alignment.

It is another further object f this invention to provide a new and improved jaw construc tion.

Yet another object of this invention is the establishment of a desired balance of forces in the relationship between the operative jaw surfaces and the jaw tensioning means.

Another general object of this invention is the provision of a new and improved cross tweezer which is simple in design, effective in construction and use and which embodies a maximum of utility with an economy of cost.

It is among the more specific objects of this invention to provide an improved crossed arm construction by which the lateral alignment of the jaws is assured, to provide a new and improved tip shape, and to provide new and improved, readily accessible and readily adjustable pincer tensioning means.

It is also among the objects of this invention to provide improvement .over prior art devices heretofore intended to accomplish a generally similar purpose. l

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawing, wherein:

Figure l is a perspective view of one preferred form of tweezer selected as illustrative of this invention.

Figure 2 is a sectional view as on a line 2 2 of Figure 1.

Figure '3 is a side view of a second form of tweezer embodying this invention.

Figure 4 is a fragmentary plan view of the clamping jaws as on a line 4 4 of Figure 3.

Figure 5 is a plan view of the embodiment of Figure 3.

Figure 6 is a detail sectional view as on a line 6 6 of Figure 5.

Figure 7 is a sectional view as on a line 1 1 of Figure 6. s

Figure 8 is a plan view of a further modified form of this invention.

Preferred ,form

Referring more particularly to the drawing, there is, in Figure 1 showna pair of tweezers comprising arms generally"lh 'designated by the numerals I0 and II.

Each suchv arm comprises, in counterpart, a tip or clamping jaw portion I 4 included in a head generally designated at I5, a shank I6, a handle I1, a flexible portion I8 and a butt portion I9.

The entire tweezer may be made of any suitsecured together as by rivets 35.

able material such as metal, plastic, or the like, but it is preferably of spring steel. The tip I4 may be of any desired shape but as shown comprises an essentially rounded point 2I having eitner smooth or serrated opposing faces, the heel of which is designated by a dotted line 22. The jaw or tip I4 may be integral with the head I5 which may be of any desired length proportioned with the length of the handle I1 in a manner to permit easy use in difficult places. The main body of the head I5 is preferably not in abutting relationship with its counterpart in the opposite arm I or II in order to bring maximum pressure to bear upon the confronting pinching surfaces extending in the illustrated embodiment in question from the point 2I to the heel 22 in order to bring maximum pressure to bear upon such operative surfaces, as stated.

The shank portion I6 of each of the arms may include a body portion 24 and a slotted or cut-out portion 25, each of which preferably occupies approximately one-half of the Atotal width from the side 26 to the side 21 of the tweezer. By this construction the lateral surfaces 29 of the shank 24 of the respective arms I0 and II may be positioned in contiguous and preferably slidable relationship to one another in order to preserve a desired alignment of the jaws I4 and to guide the opening and closing movement thereof.

As illustrated, the shanks 24 cross one another in an imaginary plane equally dividing the tweezer between the tips I4 and extending longitudinally of the tweezer. By this 'construction the cut-out portions 25 permit the uniform movement of the shanks 24 and maximum open movement of the jaws I4 is occasioned by the appropriate shape and positioning of the marginal edges 3| and 32. Optionally, if desired, one of the arms II may be formed straight so that the shank 24 is in alignment with the handle I1 as is also then the head I although such a construction except for special purposes is not preferred.

The head I5, the shank I6 and the handle I1 are preferably of the same thickness so that this portion of the body of the tweezer may be distinct from the flexing portion I8 which latter, because of its resilient quality and the mode of its assembly in the nished article, n-ormally .1:

urges the jaws I4 into yieldable closedV relationship so that they are opened only by squeezing the handle I1.

At the butt I9 of the embodiment under discussion the side or arms I9 and I I may be firmly For such purpose the butt I9 of each arm may be provided with a shoulder 36 similar to the shoulder 31 dividing the handle I1 from the flexing portion I8 but disposed upon an opposite side of the corresponding arm I0 or II so that in the finished product the thickness of the butt portion of each arm is approximately the same as the thickness of the handle portion, 'for example, of the tweezer.

In the form above discussed it is generally intended to produce the nished product with a pre-determined amount of tension for closing the jaws which, unless the arms be sprung apart laterally and spread and then-realigned, will not be subject to ready alteration.

Modified form The modified form of the invention disclosed in Figures 3, 4, 5, 6 an'd 'l is substantially similar in the shape of the head I5, shank I6, handle I1 and flexing portion I8 of the embodiment of Figures l and 2 and are therefore designated by like reference numerals. In the modified form, however, one arm, generally designated by the numeral 49, is formed with a tapered butt 4I and the other arm 42 is formed with a similarly tapered butt 43. A space 44 of wedge shape is formed between the butts 4I and 42 by their confronting flat faces 45 and 46, respectively. A pintle-like abutment 48 is thereby formed at the forward end of the butt along a line of contact between the two faces 45 and 46.

If desired, said faces may also be formed with one or more transverse tongues and grooves as illustrated in dotted outline in Figure 6 and designated by the numeral 49 (see also Figure 4).

` The transverse tongue and groove construction restrains the arms 4e and 42 from relative longitudinal sliding motion which might displace; the jaws 5I and 52. A transverse tongue and 'groove construction 53 or other appropriate mutually intertting surface irregularities on the faces and 45, or the like, may further serve to prevent lateral or .other sliding movement of the arms 40 and 42 relative to one another.

rIhe surface of the butt 43 may be formed with a rounded socket 56 into which the balllike head 51-or the like-of a bolt 5S including a threaded shank 59 may be accurately fitted. A knurled nut or disc 60 optionally formed with a boss 5I may be accurately tted to the corresponding face of the butt 4I. If thus formed with 'a boss 6I, the butt 4I may be formed with a corresponding cylindrical recess G5 in which the bolt SI may rotate.

The shank 59 of the bolt 58 may be similarly accommodated in a slot communicating inwardly with the socket 56 and having a longer axis longitudinally of the tweezer than transversely. In this manner the shank 59 may move slightly longitudinally 'of the tweezer with the ball 51-as a fulcrum when the nut 60 is turned for squeezing together the slanting faces 45 and 46 when tensioning the jaws 5I and 52 or, 'conversely. when relieving pressure on said butt 4I and 43 by unthreading said nutr60 from its normal threaded engagement upon 'the shank 59. The lthreaded recess within the boss II may, but need not, extend entirely through the nut 60. It is preferable that the shank 51 be accommodated only in theboss or ina portion of the nut 60 so as to give the nut 60 an exterior finished, undrilled appearance. y

The diameter of the nuti! preferably conforms to, or even exceeds, the diameter of the rounded ends of the butts 4I and 43 in order that it may be readily grasped and turned for altering the tension of the tweezer.

Another tensioning device used either in conjunction with or separately from the'nut mechanism 6I) heretofore described may consist in the provision of a threaded pin 19 projecting inwardly from the handle portion `I1 upon which a knurled disc 1I, also optionally provided with a boss 12, may be threaded. A spring, such'as coil spring 13, may normally encircle the pin 10 and also the boss 12 and may extend between the undersurface 15 of the disc'1I and the inner surface 1-6 of the lower handle I1 where 'it may be held against relative lateral slidable movement by Vmeans of a second pin or stop 11.

The diameter of the disc 1I is, like the nut 60, preferably sufcient to carry it to or beyond the edges 26 and 21 of the tweezer, thereby likewise facilitating its manipulation.

Obviously, the turning of the nut 60 onto the shank 59 of the bolt 58 and/or the rotation of the disc 1| in a direction away from the handle |1 next to which it is illustrated, will result in tensioning the jaws 5| and 52 in their abutting relationship with one another, in the rst instance by compression of the butt portions 4| and 43 towards one another thereby rocking the right hand side of the tweezer as illustrated on the abutment 48 to force the handle |1 apart or the jaws 5| and 52 together, or, in the second instance by directly forcing the handles apart. As stated, the construction associated with the nut 60 or the disc 1| may be used in any individual tweezer either separately as the sole tensioning means, and in conjunction, and likewise in addition to, or even in the absence of, the springy tensioning portions I8. Each adjusting means may also be calibrated or preset, either separately, or together.

The jaws 5| and 52 may each be formed with a peripheral rim 80 in the manner of lips which on their adjacent surfaces may either be smooth or toothed. It will be apparent that the degree of pressure exerted between the rims 80, the total force on the tweezers being equal, will be greater per unit of area as the rims are narrowed to approach a cutting edge. In view of this fact, it is obviously desirable to give them an extent of pinching surface sufciently great to avoid their cutting the materials upon which they are intended to operate.

For additionally insuring a proper alignment of the respective arms of the tweezer, particularly where tensioning adjustment is desired, an upstanding ange or rim member 85 may be formed at the edge or heel 81 of one of them while the other may be shaped with a rounded edge 86 of lesser diameter than that of said heel 81 of the tweezer, thus insuring a close fitting joint of the two butt portions whereby they are immobilized one within the other against lateral movement in one direction.

Further modified form The embodiment of Figure 8 comprises arms and |0|. The arm |00 may be formed with a pair of shank members |02 and |03 while the f shank |04 of the arm |0| may be centrally disposed between the shanks |02 and |03. The three shank members thus constructed will have an intertting relationship having their adjacent edges indicated at and |06 in proximate preferably slidable relationship with one another to insure proper alignment of the tip |08.

The shanks |02, |03 and |04 preferably bear a crossed relationship to one another in a similar manner to the shanks of the former embodiments. Thus, the shanks |02 and |03 may be turned upwardly at an angle of approximately 45 degrees while the shank |04 may be turned downwardly at a similar angle so that the mode of operation of all of the embodiments, so far as any single opening and closing operation is concerned, is substantially similar.

Suitable knurling ||0 may be provided upon the handle portion and the butt portion ||2 may be made adjustable for tensioning the tweezers to any desired extent as set forth in the embodiment preceding or it may be formed with rivets as in the first embodiment, or in any other manner known to those skilled in the art of tweezer construction.

The tip |08 ares 'out from the tapered neck l5 and may be substantially flat between the front slanting edge H6, the heel ||1 and the sides i8 and ||9 thereof or formed with clamping lips as heretofore described. The points |20 and |2| may be rounded in order that the tip |08 will have a maximum utility by providing round edges |20 and |2| as desired, whose side forms an obtuse angle, as at |20, or an acute angle, as at |2|. The sides ||8 and ||9 may be used with equal effect as the edge ||6 although the latter has proven to have more general utility. Essentially, therefore, the tip as shown possesses a plurality of possible operative edges and thereby a multiple utility.

This invention features the provision of a tweezer construction of great efhciency and precision and which is normally held in a closed position of either pre-tension or adjustable tension by virtue of one or more new and improved tensioning and aligning devices. It likewise features a new and improved tip construction correctly calculated to cooperate with a selected tension to achieve the best possible clamping action with the least amount of operative resistance of the instrument.

It will be apparent that the invention lends itself to modification in the shank construction, any or all of the features of adjustability, and in butt structure intended to insure, either singly or in plurality, proper alignment and operation of the parts as well as an over-all construction and design.

Although the invention has been herein shown and described in which is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described my invention herein, what I claim as new and desire to secure by Letters Patent is: Y

l. In a pair of tweezers comprising a pair of generally flat elongate opposed arms crossed between their ends and including respective notched portions to accommodate the opposite arms, said arms each having a springy portion adjacent a first end and a gripping tip at its other end, tension adjusting means common to said arms at said flrst ends, said first ends being rigid; a ridge on the inner surface of one of said arms and a groove in the inner surface of the other arm, said ridge and groove forming a pivotal connection between said arms along a line spaced inwardly from the outermost extremities of said first ends, said first ends between said tongue and groove connections and said outer extremities including matching bores extending therethrough from side to side thereof, said first ends having respective outwardly diverging confronting faces, said tension adjusting means including a threaded bolt extending through said bores and a complementary finger piece having threaded engagement with said bolt, said finger piece comprising a disc having knurled edges projecting outwardly to the corresponding outer edges of the tweezer arms, said tweezers being held in adjustable clamped relationship by means of said bolt and finger piece, rotation of said finger piece serving to vary the degree of divergence of said confronting faces of said rst ends relative to one another and adjusting the tension of said gripping ends connection.

2. A pair of tweezers as defined in claim 1,

said adjusting means further comprising a coil spring positioned between the arms of the tweezers land having its outermostl edges spaced inwardly from the corresponding outer edges of said arms, centering means extending inwardly from the innervsurface of each said 'arm for restraining spring against radial displacement, -said Vcoil spring normally urging said arms apart, one of -said centering means comprising a threaded studand a knurled disc, including -a central shoulder positioned within the corresponding end of the coil-spring, said last. named knurled disc being threaded on said stud and normally lying ush against the inner surface of lthe corresponding tweezer arm, said disc providing an adjustable abutment for the corresponding 'end of `said coil spring, and the knurled edge of said disc extending outwardly beyond the corresponding edge of said tweezer arm, whereby rotation of said knurled disc serves to adjust the effective tension of said coil spring between and against said arms.

CHARLES J. LO MONTE.

REFERENCES CITED The following references are of recordin'thefile of this patent:

UNITED STATES PATENTS Number Name Date A 274,695 Badger Mar. 27,'.1883 389,925 Griscom Sept. 25, 1888 450,266 Truax Apr. 14, 1891 721,379 Martin Feb.v 24, 1903 896,338 Tohnan Aug.18, 1908 964,181 Phesay July 12, 1910 1,004,871 Gundorph ,Oct, 3, 1911 1,133,334 Strycker f Mar. 30,- 1915 1,456,844 De Bie May 29,1923 1,679,196 Zieburtz July 31, 1928 1,785,919 Stickel et al Dec. 23, 1930 1,889,475 Henkel Nov. 29, 1932 2,082,062 Johnson June 1. 1937 FOREIGN PATENTS Number Country -Date 234,350 vGermany May 11, 1911 684,925 France Mar. Y25,v 1930 231,930 Switzerland July 17,1944

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