US26627A - sttjr - Google Patents

Description

UNITED STATES iziiinivrOFFICE. i; f

LATHE ATTAcHMENrFoR CUTTING vENnERsLf if i, i i Specification of Letters Patent No. 26,627, dated December `2'?, i

a slot c in the knife. `'Ihis knife is adjusted i `1 y in heightby set screwstcl, and is beveled,las y f shown in Fig.-2. "I i 11 t A flatpresser bar C" issecuredto the top 60 of the block A, by means of a clamp D and screws e passing throughmslots fjinthefban l, which allows the position of this bargtofbe` adjusted. Its z front edge `g i isz `beveledas` i shown `in Fig.` 2, thebevel onthe lower side a5 *Y corresponding orinearlyso with the bevel on the back of theknife B. i The upper `iside: y at its front edge `is turned up,";fo`rming*a lip l or rabbet 5 alongthisedge which lis notched f1 as shown in Figi lgfThe chisels or icutters70"` E, El, E2 reston the "presser "bar C and""are held firmly in position byi the `clamp D, their l n y To all whom it may concern: Y i 1V ,i Be it known that I, B. F. STURTEVANT, of 1 i Boston, in the county of Suffolk and State of Massachusetts, have invented certain Im- 5 provements in Tools for Cutting Sheets or Strips from the Surface of Cylinders or Blocks of Wood, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, making part of thisspecification, `in which- Figure 1 is a view of the cutting tools and the block or rest to which they are attached.v Fig. 2 a transverse vertical section through the same.

Veneers have been cut, both from the surface of a cylinder of wood revolved against a knife, and also from a block of wood which was carried back and forth by reciprocating machinery over the knife. Sheetsof wood could be thus cut, when they were quite thin,

front or cutting :ends resting in the notches 5 which preventsffany undue` vibration.: "l These cutters are only used when the widtl'i y of the sheet cutbylgthewknifeBiis lesstthalfil the length of the cylinderor block; orlwhenj 1 the sheet is to bedivided intonarrowpribbons. i i i i ff Operation: The following is the operation of the above described tools, `and thema; chinery connected therewith when cuttingf` sheets froma cylindermofwood. `The logto be operated upon, having been previously turned to a cyllnder, isgrevolved slowly in a 85` v lathe; the block isattached to the slidef `I rest, orV occupiesV a similar position at Ithe` front of the lathe, uso that it can be moved` j lengthwise of the lathe forthe knifeB to y i operate on different parts of the lengthofy?? the lo This knife is placed with itslcut-i f ting e ge in or near a horizontal plane pass# l H ing through the axis of the log. The block i A is fed horizontally by suitable :rnechanismp` i y toward the log, for this purpose I use screws 9,55 and gears, which may be varied to give the" block A the proper feed relative tothe speed f at which the logis revolvedpto cause the t knife B to cut into the log to a` depth suiii` t cient to produce the sheet of wood of `there-` `100 quired thickness. The sheet of `wood "thus 1" produced passes down throughthethroata 3 and is removed by the attendant; i The A screws and gears regulate the thickness of), the sheet to becut, but I set the presser `bar I; C, so that the space between its edge g and y the cutting edge of the knife: B `shall beless than the distance `which lthe knife is fed for a singlerevolution of the log, or less than the (as for veneers) but when a thicker sheet or strip was to be cut from the wood, either around the log, or across the grain of the block, and where a thicker knife was required; the wood was liable to be split partially or entirely through the thickness of the sheet, which `did not then retain suiiicient strength for the uses to which it. was to be applied (for example, stuff for picture frame backs, bottoms of drawers, Y and when cut narrow for blanks of shoe i pegs). To remedy this is the object of my ,1" y present invention which consists in applying a considerable amount of pressure to the surface of the wood, in the immediate vicinity of the cutting edge of the knife; by which means the splittin `or crippling of the wood is prevented; and t is pressure I apply by means of a presser bar, the position of which is so adjusted with respect to the edge of the knife, that the space between the bar and knife shall be less than the distance which the knife is fed up at each revolution of the log, or each vibration of the block. t

That others skilled in the art may understand and use my invention I will proceed to describe the manner in which I have carried out the same.

In the said drawings A is a block of metal which is attached to or occupies the place of the ordinary slide rest in a lathe. This block is cut away at a to form a throat for the passage of the sheet of wood, the length of this recess corresponding with the length of the knife B, which is secured to the front of the block A by a screw b passing through thickness of sheet due to the feed, so as t0l l, cause the edge g to `be pressed with a con#` siderable degree of force againsttheeXte-I rior surface of the Wood, opposite to or immediately in advance of the edge of the knife. The position of the edge g With respect to the edge of the knife being governed by the thickness of the sheet being cut and the quality of the Wood; the thicker the sheet and the tougher the Wood, the higher it may be raised above the plane in which the knife is fed toward the aXis of the log.

I have found in practice that when the pressure is not applied to the Wood in t-he vicinity of the edge of the knife B when cutting around the log, as above described that the sheet taken ofi' is so crippled by the thickness of the knife,-that it breaks easily.

Instead of securing the presser bar C rigidly to the block A a strong spring may be employed to press it up Wit-h sufficient force against the Wood being cut.

The cutters E, E, E2 are used to separate the edge of the sheet from the log, and to divide it into ribbons of the required Width, the cutter E is placed opposite to the inner end of the knife B and cuts in a little in advance of the knife separating the sheet at its edge from the body of the log, leaving the end of the log Where it has cut, square ready for the neXt cut of the knife B. (This cutter as Well as the end of the knife B is set iush With the end of the block A.) The cutter E2 squares the end of the log When making the first cut around it With the knife B, leaving the outer edge of the sheet straight; or if the end of the log has been squared previously, this cutter may be dispensed with, The cutter E divides the sheet in the middle of its Width. Any suitable number of these cutters may be em ployed.

These tools may be applied in a similar manner to cut sheets or ribbons from a block of Wood, the feed in this case being intermittent.

lVhat I claim as my invention and desire to secure by Letters Patent isl. Compressing the Wood in the immediate vicinity of the edge of the knife by means of thepresser bar C or its equivalent, arranged and operating substantially as set forth.

2. I claim the cutters E, E, E2 or their sulstantial equivalents for the purpose speci- B. F. STURTEVANT.

Witnesses:

THos. R. ROACH, P. E. TESGHEMACHER.

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