US 2634498 A
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April v 14, 1953 A. ABRAHAMSEN SCRAPER Filed June 16, 1950 Hmnnllllmmr a R. J ad 0 y) WM i "'lllllll//l @www l Patented Apr. 14, 1953 vUNITI-:o STATES PATENT GFFICE 3 Claims. (Cl. Sil-171) This invention relates to a scraper for smoothing and nishing wood surfaces and the like and in particular a scraping tool to which pressure is applied directly over the blade.
In the present invention, I construct a sturdy scraper of light materials with blade, head and handle assembled to reinforce each other so. as to form a rigid structure.
In carrying out my invention I provide a head made of a pair of clamping plates which form reverse angles with a connecting shank so that a' removable blade can be held in place. This blade, in the shape of an elongated Z, has one iiange securely mounted behind the shank of the head while the second iiange is in scraping position. In use. I find that to make the scraper an eiicient smoothing tool it should not be resilient to uneven surfaces. I solve this difficulty by making my handle U-shaped with the upper bar elongated to clamp directly to the blade and head, forward of the shank. When this is done the upper bar to which pressure is applied conveys this pressure forward of the shank so as to make my structure rigid and obviate bending of the head. The lower bar of the handle is also clamped to the head but rearward of the shank. This makes an open loop which protects the knuckles against banging on the work.
By thus locating the handle where it will give the necessary reinforcement to the head, I make my structure so strong and rigid that I may use light materials to construct an inexpensive scraper which has been shown in operation to be sturdy and eiiicient. This construction also enables me to use a very thin Z-shaped blade easily removed and reversed which I strengthen by bowing the two flanges to form shallow cylindrical segments.
This invention can readily be understood by reference to the accompanying drawing in which Fig. 1 is a top view of the scraper; Fig. 2 is a side elevation view; Fig. 3 is a iperspective view of the blade; Fig. 4 is a perspective view of the head and Fig. 5 illustrates this invention in a modied form.
Scraper I0 as illustrated in the drawing has a removable blade I2 with a pair of reversible cutting edges I4 on flanges I6. These flanges form reverse obtuse angles I8 with the body of the blade. In the preferred form of my invention shown, I strengthen flanges I6 by curving or bowing them to form shallow cylindrical segments. With these cylindrical segments I may automatically vary the depth of cut. For instance, by rotating the scraper in a counterclockwise direction, cutting edge contact with the l" shank 26. Clamping plate 22 and shank 26 form, an obtuse angle 28 similar to obtuse angle I8 soy that one flange of the blade ts snugly against the shank and the second ilange is held approximately perpendicular to the Working surface (see Fig. 2). In scraping, I slide cutting edge I4 across the work only in the direction of the handle andl prev-ent twisting-of the blade by tting one flange against shank 26. This also distributes the forcel required to slide the scraper over rough surfaces to substantially the entire flanged area held behind shank 26. Otherwise this force is trans-. mitted solely by a clamping bolt which. might" have a tendency to distort the' blade. Thus, I
may use a very thin blade easily sharpened by al burnisher reducing the necessity for frequent grinding. It is to be noted that the idle blade cannot be damaged in its protected position behind the shank.
Clamping plate 24 extends at an approximate right angle from shank U-shaped handle 30 by lower bar 32. Upper bar 34 is elongated and curved over shank 26 to form extension 36. I iind that by clam-ping extension 36 forward of the shank, the bearing pressure oi scraping is applied directly over the blade to obviate bending of the head, and the scraper is materially strengthened.
The blade and handle may be clamped to head 20 by any desired means but the important thing is that the blade may be easily replaced. For this purpose, I show in Fig. 2 a screw and wing nut indicated at 38 for holding upper bar 34 of the handle and blade I2 to clamping plate 22 by means of corresponding holes 40 and lower bar 30 is mounted on clamping plate 24 by rivets 42 and corresponding holes 44. Any suitable material may be used to form my scraper but I prefer to make the blade out of carbon steel approximately 25-30 thousandths of an inch thick and to construct the head and handle of aluminum.
A modied form of this invention is shown in Fig. 5 with the blade detached and shown immediately below the head. In this modification the angles of the -blade and head members are identical with the primary form of my invention. Scraper 46 has a removable blade 48 with a pair of reversible cutting edges 50 on flanges 26 and mounts a' 52. On either side of the central portion of the blade are notches 54. Head 56 has two clamping plates 58 and B0 with connecting shank 62. Tabs B4 located on either side of clamping plate 58 are adapted to t tightly into notches 51 when a blade flange 52 is in position against shank 62. Normally ange 52 prevents twisting of the blade but when worn off by repeated sharpening it tends tobecomeless effective .andinsuch case tabs B4 and notches 5B cooperate topreveritJ blade twisting. Handle 66, in the general form of a U, has a lower bar -68 and an upper bar l0 elongated and curved over shank 62 to form extension '12. The opposite closed end of the handle is also curved and extended to form guard .'M for knuckle protection. So formed this modiedscraper may be assembled by the samemeansfshownin Figa-2 and described above.
It will be understood .that it is intended "to cover all changes and modifications of the preferr-ed embodiment .of :this invention herein chosen 'if-or the purpose :of illustration which do not constitute :departures from '-the .spirit :rand scope of the invention.
`-What 1I claim is:
Z1. 'adevicebf the ltype described, .a twoedged 'removable Vblade 5in `fthe .general .form bof anelongalted l2, i'comprisingia "central `portion and twoV ianges, said ilanges having .cutting edges, each :ange ziormin'g :an :obtuse :angle with `the central portion .and 'each ;of .said :edge portions being bowed to .form a :shallow :cylindrical segment, fa .head comprising 'a 'loody portion, a clamping yplate `adapted 1o receive the central portion .of said vblade "and Va connecting shank which holds'the bladezclamping pl-ateat an .obture angle with .said .body portion, `a looped handle in tha-general :former-a VU .having a loner and short arm, saidshort :arm being connected withrthe bodyportionof said :headfand said long arm `fbeing connected with Vsaid `blade clamping plate of -thehead to apply bearing pressure over the ventire central Aportion of the blade when scraping, readily detachable means for clamping the blade to said blade clamping yplate of the head, -oneiiange of said blade .being covered by the head and said obtuse angles of the head and blade Vcooperating .-to vhold the second edge 4 perpendicular with the work when the handle is held parallel with said Work.
2. A structure as specified in claim 1 in which the closed end of the U-shaped handle is curved and extended below the horizontal plane of the lower arm to form a guard to protect the knuckles against banging on the work.-
3. In a device of the type described a twoedged ,removable blade in `the Ageneral form of an elongated Z comprising a central portion and two anges, said flanges having cutting edges,
veach ange forming an obtuse angle with the central portion and each of said flanges being ubowed to form a shallow cylindrical segment, the blade having `a notch centrally located on either side of its central portion, a head comprising fa lbody portion, a clamping plate adapted to receive the central portion of said blade and -a connecting shank which holds the blade clamping plate at an obtuse angle with said 'body .,portion, said head having 1a .pair :of V:'tabs,
each tab being `centrally located on .either side of said blade v,clamping plate of the head 'and adapted to t said :blade notches, a looped handle having along ,and short arm, `said short arm being .connected with 'the body portion ,ozf-v said head and said long arm being connected with said blade clamping Vplate iof the `head to apply .bearing pressure over the entire Acentral portion of 'the bladewhen scraping, readily detachable means for clamping the blade to saidblade clamping plate of the head, one .ilange of said blade being covered lby Ithe head and said obtuse angles lof the head and blade co# operating to hold the second flangeperpendicular with the work when the handle ,is held parallel with .said work.
`References Cited in the le of this patent UNITED STATES PATENTS Number Name lDate 1,765,812 White ,et al. June 24, 1930 1,903,877 Potter Apr. 18, A1933 1,910,087 Charlton May v23, 1933 2,259,662 Roberts Oct. 21, 1941