US1822050A - Shears with detachable blades - Google Patents

Description

Sept. 8, 1931. c. E. LLIEDTKE 1,322,050

SHEARS WITH DETACHABLELBLADES Filed March 8, 1928 Patented Sept. 8, 1931 UNITED STATES PATENT OFFICE CHARLES E. LUEDTKE, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR OF ONE-HALF TO U FORREST SKYIIAXVK, OF STEWAB-TVILLE, MINNESOTA SHEARS WITH DETACHABLE BLADES Application filed March a, 1a2s.

, This invention relates to shears and especially to shears having detachable or replaceable blades and is an in'iprovement on my invention illustrated and described in my Patent Number 1,615,882, issued February Heretofore shears employing detachable blades have been used, but for the most part such devices have been unsuccessful either because they were of cumbersome construction and hard to handle or because they were costly to manufacture. r It is the main object of this invention to provide an extremely simple pair of shears of specialutility for. barbers, wherein detachable blades are provided, said structure being adapted for manufacture at low cost and be ing such that the bladeportions of the shears including the detachable blades and the mountings therefor are of substantially the same shape and thickness as shears now in common use.

A further object is to provide in shear structure detachable blades interlitting with the hinged mountings of the shears in such a way that theywill not require the manipulation of clamping parts. i A further object is to provide in a device of the class described detachable blades 'having rabbeted portions interfitting with rabbeted portions of their mountings said portions in bothcases being adapted for manufacture at low cost and fixed retaining means in conjunction with said parts, said retaining means being of such nature that they will not obstruct'or catch on articles, such as fabric and that when the shears are. in normal position or in operation the blades will be securely locked therein.

These and other objects and advantages of the invention will be apparent from the following description made in connection with the accompanying drawings in which like reference characters refer to similar parts throughout the several views and in which:

Fig. 1 is a plan view of embodiment of the invention, the shears being in closed position;

Fig. 2 is a side elevation of the same;

Fig. 3 is a plan view of the shears with Serial No. 260,012.

the pivoted mountings in extreme open position for attachment or removal of the blades;

Fig. 4: is a cross section taken on the line 4- 1 of Fig. 1'

F ig. 5 is a cross section taken on the line 55 of Fig. 1; Fig. 6 1s a perspective view showing th construction of the rabbeted portion of the mountings and the detachable blades and comprise a pair of shanks A and B intermediately pivoted bymeans of a suitable pin or screw 8. The handle portions of the shanks as shown are of circular cross section and terminate in a pair of handles 9 and 10 respectively, handle 9 being adapted for manipulation by the thumb and handle 10 having a projecting finger piece 10a. The opposite arms of shanks A and B constitute the mountings for a pair of detachable blades, and as illustrated comprise substantially flat arms tapering fro-m pivot 8 to their outer extremities. The inward or opposing faces of the blade mounting arms are rabbeted at 11 and 12 respectively, said rabbeted portions extending from points adjacent pivot 8 to the diminished extremities of the mountings and being of substantially half the width of said mountings. The inner ends of rabbets 11 and 12 are covered by the opposing face of the opposite shank when the shears are closed or when they are in operation, but when the shanks A and B are spread apart in the position shown in Fig. 3, the rabbets 11 and 12 will be exposed.

Shanks A and B at the handle side of pivot 8 are provided with shoulders 13 and 14 respectively, which i are adapted to abut to limit the closed position of the shanks. At the inward end of each of rabbets 11 and 12 I provide small inwardly projecting pins 11a and 12a respectively, said pins extending normal to the bottom surface of the rabbets. The ends of the blade mounting portions are blunt to form abutments, as will later be more fully described. At the diminished extremities of the blade mounting portions slots 11?) and 127). are formed having their outer ends'open and? extending; inwardly longitudinally of . rabbets 11 and 12.

My detachable blades comprise elongated members 15' left and right being identical- Blades 15 are provided with unrabbeted' tapered tip portions 15a terminating in points. stantially straight longitudinal cutting edges 15?) and are longitudinally rabbeted at 150*, said rabbets extending from the tip 15a. to the opposite end of the blade and being. of substantially equal dimensions with the rabbets 11 and 12 of shanks A and B.

A small pin or stud 16 is. fixed to each of the blades extending normal. to the bottom of rabbet-150 and adjacent tip 15a, said pin being adapted to be positioned within slot 116 or 12?)- of the mounting arms when. the rabbeted portions of the blade and mounting arm are interfitted. The butt ends of blades 15. are each provided with a. small aperture 17; adapted to receive either the pin lie. or the pin 12a according to the particular mounting arm to which the blade is secured.

To insert the blades 15 it is necessary to first swing shanks A and B towide open position, as shown. in Fig. 3, the inner ends of the rah-bets l1 and 12 being. exposed intliis position. Fig. (lillustrates the mannerin which the blades are attached. The rabetted portions are matched and. the operator slides the blade longitudinally 'and inwardly toward pivot 8', causing slot and. pin engagement between the pointed end of the blade and the extremity of the mounting; arm.. The butt end of the blade is then pressed inwardly against the inner end of the rabbet, apertures l7; accommodating the pin 11a. [issuming both blades attached in. the manner described they may be locked against displacement by merely closing the shanks A and 13.. Unless desired no additional retains ingi means need be applied for. securing the blades.

However, as shown, I. may provide small clip-members 18 which may be fixed to pins 111.2 and 1260 respectively, comprising angle springs-having relatively short inturned. ends 180 adapted to yieldingly engage the inward extremities of the cutting edges 15b of. the blades when the blades are forced inwardly to engage the pins 11a. and 12a.. In the event that blades 15 are shorter than the blades illustrated andconsequently cannot-be held in place by the opposingfacesof the opposite shanks my'retaining clips 18. would hecome-necessary;

It will-be seen that. my shears may be manufactured with the cutting portions of the Blades 15 have the sharpened sub-- reeaoso shanks of similar thickness to shears now in use, since no cumbersome attachments are necessary for securing the blades to the mounting arms. The complementary rabbeting of the blades and mounting arms together with the simple. slot. and pin. locking engagement. and pin retaining means: afloi'd highly efficient structure which may be made similar in weight and thickness to the ordinary type of shears now: used. No: difficult machining. of the parts is'necessary to produce the interfitting rabbeted portion, dovetail grooves and mortise and tenon blades are dispensed with. My device is, therefore, adapted for manufacture at low cost.

Theadvantages of the: device. are probably obviousfrom the-preceding-description. New blades may be inexpensively obtained and can be quickly substituted for the old; ones. The life of the shears is thus greatly pro longed and sharpened edges are always as.- sured. In grinding shears, the longitudinal edge is worn down causing the tips; of. the shears to. cross and in time to impair the efiiciency of the device. B'y discarding old blades and substituting new ones in. my device, this objection is obviated.

It will, of course, be understood that" variouschanges may be made in the form, details, arrangement and; proportions of the partswithout departing from the scope of the invention.

What is claimed is:'

Shears comprisinga pair ofintermedfiately pivoted blade holding members having longitudinally rabbeted portions on their opposing faces, said rabbeted portions extending in length from the outer ends of said members to points adjacent the. pivot of said blade holding members, detachable blades having longitudinal rabbeted' portions extending from the tips thereof to their opposite ends, the rabbeted portions of said blades interfitting with the rabbeted. portions of said b ade holding members to substantially equal the thickness of the unrabbeted portions of each, thev extremities of said blade. holding members abutting and interlocking-with the tips of said blades'and spring clips aflixed to the outer faces of said blade holding members adjacent the; pivot and" having free turned ends-adapted to yieldingly engage the inner extremities of the cutting edges of the blades to retain the blades against lateral displacement.

In testimony whereof I. affix my signature.

CHARLES E. LUEDTKE.

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