US2304470A

US2304470A - Machine for resawing slabs

Info

Publication number: US2304470A
Authority: US
Inventors: Edward E Marshall; Chester B Zumwalt
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-06-06
Filing date: 1939-06-06
Publication date: 1942-12-08
Anticipated expiration: 1959-12-08

Description

Dec. 8, 1942. E. E. MARSHALL. ETAI; 2,304,470

MACHINE Fon RE-awme sLABs Filed June 6, 1959 :s sheeis-shet 1 fon/Airb f. la H-sgr?? h! Zumwnur c/-i-M/ T RN A Dec. 8, 1942. E. E. MARSHALL ETAL 2,304,470

MACHINE FOR RE-sAwmG sLABs 3 sheets-sheet 2 Filed June 6. '19:59

la- [El .Moy u m ER IM Zwmmw f E i ATTORNEY- 5 a" Dec. 8, 1942.

E. E. MARSHALL TAL MACHINE FOR RE-SAWING SLABS s sheets-#sheet s Filed June 6. 1959 0 3 m. aw l ,m 2 .....|..|Ul|| nw. l n l .4-.. o Q 5 .2 1 l5 2. E 4 .1 ...x 70].. a 0...,.9 2 .4 :6 3 .I 5. 3 4 l 5. W Il I4.. n. 5. .3.4 l @b.

`nfvVEA/Toks fiamma f. MM5/1ML .srt-M zum/Mr A TTORN E ag Patented Dec. 8, 1942 MACHINE FOR RESAWING SLABS Edward E. Marshall and Chester B. Zumwalt, Oakland, Calif.

Application June 6, 1939, Serial No. 277,668

9 Claims.

This invention relates to machines for sawing split cedar slabs to provide a type of shake having a split surface on one side and a sawed surface on the other side.

Shakes of this type are commonly called resawed shakes and will be hereinafter so referred to. Re-sawed shakes are in demand for certain uses because they have one split surface which may be turned outwardly to give the desirable appearance and weathering qualities of a shake and one sawed surface which will t smoothly and Iirmly against sheeting or like sawed lumber to which the shake is applied.

Re-sawed shakes are made from split cedar slabs which are usually from 32" to 38" long, Vary from 1%" to 2" thick, are of substantially the same thickness at the two ends and have two split faces. Two re-sawed shakes are made from each of these slabs by sawing the slab longitudinally in a plane slightly inclined relative to the two faces of the slab or relative to the medial plane of the slab to cut each slab into two tapered shakes each shake having a thin tip and a tricker butt and each shape having one split surface and one sawed surface.

An object of this invention is to provide an improved machine of simple and eiiicient construction for re-sawing split cedar slabs rapidly and accurately and inexpensively to form tapered shakes.

Another object of this invention is to provide a machine of this nature having readily adjustable means by which the operator can vary the thickness of the tip of one of the shakes cut from each slab to secure a thin tip and yet avoid feathering the tip by cutting into the face grooves adjacent the tip, the adjustment being made to suit the individual requirements of each slab without stopping the machine and without reducing the speed at which the shakes are fed and sawed.

Another object is to provide a machine of this nature in which the danger of injuring the operator is reduced to a minimum as the machine feeds the slab to the saw without requiring the hands to be used near the saw."

Other and more specific objects of the invention will be apparent from the following description taken in connection with the accompanying drawings.

, In the drawings, Fig. 1 is a plan view of a machine constructed in accordance with this invention, parts being broken away.

Fig. 2 is an end elevation of the same taken substantially on broken line 2-2 of Fig. 1.

Fig. 3 is a sectional view taken substantially on broken line 3-3 of Fig. l, parts being broken away.

Fig. 4 is a fragmentary sectional view similar to Fig. 3, showing certain parts in a different position.

Fig. 5 is a fragmentary sectional view on a larger scale than Fig. 1, taken substantially on broken line 5-5 of Fig. 1.

Fig. 6 is a fragmentary sectional view of a modified form of slab support which may be used in connection with this invention.

Fig. 7 is an edge view of a cedar slab of the type this machine is adapted to re-saw.

Figs. 8 and 9 are fragmentary perspective views of the two end portions respectively of a cedar slab.

Like reference Vnumerals designate like parts throughout the several views. Y

The frame of the machine comprises upright supports or legs I0, horizontal frame bars I I and a top plate or table I 2. Two transverse shafts I3 and I4 are positioned at the respective ends of the frame and journaled in bearings I5 supported by frame bars II. Two spaced apart sprocket wheels I6 are secured to each shaft I3 and I4 and two endless link belts I'I are operatively disposed on the sprocket wheels I6. The upper lap or portion of each link belt rests on the table I2 throughout the greater portion of its length.

Transverse slab supports I8 and I9 extend crosswise between the two link belts like slats and are xedly secured at their ends to the respective link belts. The slab supports I8, see Figs. l, 3 and '7, are L shape in cross section and are adapted to receive the rear end portions of cedar slabs 20. The slab supports I9 are preferably flat or rounded in cross section and are adapted to support the forward end portions of cedar slabs 20. One slab support I8 and one slab support I9 constitute a pair. The two supports of each pair are spaced just far enough apart to receive slabs of predetermined length and several pairs of such supports `are provided on the link belts II. The distance between adjacent pairs of supports I8 and I9 may vary. Different interchangeable pairs of belts may be provided for use with slabs of different length. In practice it is desirable to provide for the handling of slabs of 32", 34"and 36"- length but obviously any desired number of length variations may be taken care of in this manner.

A band saw 2l extends crosswise of the table I2, at substantially right angles to the link belts a'. shaftv 32.

I1 with the lower 4lap thereof positioned a short distance above the path of travel of the uppermost portions of the supports I9 and the teeth of the saw turned so that the slabs will be moved into engagement withsaid teeth by movement of the link belts I1 in the direction indicated by the on the shaft 29 of said band saw wheel. The' shaft I4, that carries one set of.sprocket\wheels I6 on which the link belts I1 are disposed, is

preferably driven from the same motor by means whichsynchronizes the drive of the saw and the drive ofthe link. belts. The. driving means for shaft I4, herein illustrated, comprises a worm wheel.: 30`on shaft I4 engaged by a worm 3Lv on The. shaft 32 is journaled in a bracket 33 and has a sheave 34 connected by a belt.- 35 with. a; sheave 36 on the Asawl wheel shaft 29.

A hold down roll 31 isadapted to restvupon the slabwhich is being re-sawed. This hold down, roll. 31 is-operativelymounted in frame means 38. Theframe means 38-.is connected `by pivots 39-to frame brackets. 40. This allows-the roll 31 tomoveup andv down. freely. The weight ofthe roll.31v rests onlthe slab 26 and tends-to hold.-the'slab down. Astop. member 4I on the frame means 38 is positioned so as to engage withaguide-r-ail42 -tolimit the downward movement of the roll 31... The guide rail 42n extends longitudinally of the frame above the linkbelt `I1shownat theleft in Figs. 1 and 2. Bracketsv 43 support the guide rail 42.

Means arey provided for, adjusting` the elevation-4 of 'the slabsupports IB-that support the-rear ends, of the slabs'y 26. This means comprises twofvertically adjustable track -bars 44and 45 positioned. adjacent the outer sides of the link belts I'I and. operable in slots 46 in the table I2'. Each link belt I1 has aplurality of brackets 41= secured thereto and. extending outwardly therefrom over the track bars 44 and 45. One of, the. brackets 4-1is provided-opposite the end of each: cross bar I8. When the trackI bars 44 and.45= are .intheir lowermost position they will not .elevatethe linkbelts I1 at the location of the. slab supports I8y` and said .link belts will be supportedon. andmove on the table I2. When saidv-tracklbars 44 and 45vare raised, as shown in.Fig,. 4, then, the link belts at the -locations where the slab-supports I8A are secured are elevated by the track: bars 44 and 45. and theV slab supports" Il by which the rear end portions' of theslabs 20" are supportedareheld in an ele'- vate'dV vposition during that portion of their travel throughout whichth'e slab 29' isbeing fed' to the saw 2`II The link belts at the location of'the front slab supports i9 rest on the table during this same time. The two

track bars

44 and 45 maybe connected by a cross bar 48. Also each of said track bars 44 and 45V is provided withv two

inclined surfaces

49 and 59 positioned near the respective ends of the track bar. The inclined surfaces. 49 are slidable on a fixed cross rod 5I and the inclinedsurfaces 59 are slidable on" another xed cross rod 52. A cross shaft 53 positioned near the intake end of the machine has short lever arms 54 xedly secured thereto. These short lever arms 54 are connected by pivots 55 with the ends of links 56. The other ends of links 56 are pivotally connected with the cross shaft 48 which connects the two

track bars

44 and 45. A hand lever 56 is secured to the shaft 53 at one side of the machine to provide means for rotatively moving the shaft 53. A notched quadrant 59 is provided for the hand lever 58 to engage with whereby the hand lever may be held in any desired position.

`An edge view of one of the cedar slabs 20 is shown in Fig. '1, and 'fragmentary perspective views of the end`portions of said slab are shown in Figs. 8 and 9. Cedar slabs of this type are splitV from cedar blocks or bolts. These slabs are of approximately the same thickness at both ends and both faces thereof are split faces. The grain of the wood is substantially perpendicular to the plane of the slab. These slabs are split with a tool having a flat sharp edge, such as a frow. Where the frow enters. the block in split.- ting the slab the face of the slab immediately adjacent the end willusually be fairly flat and smooth and-free from ridges. A .at face portion l60 adjacent the end of a slab is shown in Fig. 9, and is indicated by a tapering out of the dotted line 6I in Fig. '1L At all other locations the face of the slab will be aY true split surface with the usual grooves 63 and ridges produced by the grain. Wood from some trees will split with deeper grooves and'higher ridges than from others. Also woodfrom different parts of the same tree may show substantialv variation in depth of. grooves l63 when split. These slabs are resawed to form two tapered shakes from each slab. The line of the cut in re-sawing is indicated by dot and dash line 62 in Figs. "I and 8. Ihre-sawing these slabs it is desired. to produce shakes that are shin at the tips. However if the saw cut runs into the deeper grooves, such as the grooves 63 inFig. 8,v so as to leave notches inthe thinner end of the shake and produce a feathered tip then-the shake is rejectedl as imperfect. It is.v to avoid having, the saw intersect the bottom portions of the deeper grooves-63 that we provide means byl which the operator can vertically adjust the rear end of theslab toward'or awayfrom thel table to providethe correct cut for each individual slab. This variation. in the depth of grooves in the face vof the slab at the location where the split#- ting tool entered the slab is usually not enough to require adjustment by the operator to the successive individual slabs. However, in Fig.. 6, I have shown a modified. form of adjustable cross bar means. for supporting the forwardV endportion of the slab. This cross. bar. meansv comprises a cross bar 65 extending between the two link belts I1 and xedly secured to said link belts and a shake supporting member mounted on the cross bar 65 by means of screws 61 and spacer members 68. By removing the screws 6I and substituting spacer members 68. of different thicknessthe supporting member 66 may be vertically adjusted and this adjustment will vary the respective thickness. of the shake tip and butt formed at the forward end of the slab.

In the operation of this machine an operator stands. at the forward end of the machine and feeds the machine by placing the slabs 20 one at a time in the machine withv one edge of the slab resting against the guide rail 42', one end ofthe slabl resting in an L shaped slab support I8 and lveyor adjusting devices 'a 4smooth forward end portion 60 of each slab is thus supcorresponding to the is to be made. As the slab is fed forwardly to the rapidly moving saw said slab is cut into two shakes. If the operator introduces a slalb which does not have deep grooves he moves the lever 58 forwardly to lower the slab support I8 which We claim.: 1. A machine for sawing wooden slabs to form from `each Wooden slab two tapered shakes each O having a thicker end portion portion, comprising a horizontal support;

control devices adapted to vary the incline of slab while the slabs are being cut by the saw.

2. A machine for sawing wooden slabs to form from each wooden slab two tapered shakes each having a thicker end portion and a thinner end portion, comprising a horizontal support; a band saw operable horizontally across said support; belt means movable horizontally across said support in a direction substantially at right angles to the length of the band saw; pairs of transverse slab supports carried by said belt means, each pair of slab supports comprising a support for each end of a slab, the two slab supports of each the saw.

3. A machine for sawing wooden slabs longituslightly inclined relative medial plane of the slabs to form from each wooden slab two tapered shakes each having a thicker end portion and a thinner end portion, comprising a driven horizontal conveyor embodying two spaced apart endless link belts connected by transverse slab supports; means normally supporting the upper laps of said link belts; conoperable to verticallx7 3 adjust portions of the upper laps of said link belts that are connected with the rear end portions of said slab supports without adjusting other portions of said upper laps to vary the incline of slabs supported by the slab supports; and a driven band saw positioned with one lap thereof extending across said link belts a short distance above Vthe link belts.

4. A machine for sawing Wooden slabs longitudinally and in plane slightly inclined relative to the medial planes of the slabs to form from each usual longitudinal grooves of varying depth re- 4 sulting fromv the splitting ofthe-slabs and further has ony oneA face adjacent an end of the slab a substantiallyA smooth surface formed by the entrance off ay splitting tool, said machine compris ingfhorizontal endless *flexiblel conveyor means; a driven band saw extending across said conveyor means a short distance above said conveyor means; pairs of transverse slab supports on said conveyor means, the two supports of each pair being spaced apartl far enough to receive the front and rear end portion respectively of the slabs and support the slabs in a position inclined relative toV its` direction of movement, the front support of each pair having aflat surfaceA to receive the smooth surface near the end of the slab and provideY a rm supportfor the forward end of the slab and correctly position the forward end of the slab relative to the saw; and slab support" adjusting devices operable to vertically adjust the rear slabvsupport of each pair whereby the width of the tipof a shake formed from the rear end portion of the slab may be adjusted to conform to the depth of the split grooves in the face of the slab.

8. In a machine having a` horizontal band saw A for sawing wooden slabsV longitudinally of the slabs in aplaneslightly` inclined relative to the medial planes of the slabs to form fromV each slab two tapered shakes each having a thicker end portion anda thinner end portion, a. horizontal conveyor comprising link belt means movable crosswisefof theI band saw infclose proximity thereto; slaby supports carriedby-said linkbelt means; incline control devices connected with the rear end portions of said slab supports; and readily adjustable slab support. adjusting devices positioned in the path of said incline control devices operable to vertically adjust the rearfend portions of said slab supports whereby the in,- cline at which the slabs are fed to the saw will be varied.

9. In a machine having a horizontal band saw for sawing wooden slabs longitudinally of the slabs in a plane slightlyinclined relative to the medial planes of the slabs to form from each slab two tapered shakesV each having al thicker end portion and a thinner end portion, a horizontal conveyor, comprising link .belt means-movable crosswise of the band sawin close proximity thereto; pairs of transverse slab supportsl carried by said link belt means, each pair of slab supports comprising a support for each end` portion of a slab, the two supports of eachpair being positioned to supportv a slab at an incline` relative to its plane of movement; and slab support adjusting devices operable to vertically adjust the supports for the rear'end portions of the slabs, whereby the incline at which the slabs are fed to the saw will be varied.

EDWARDE'. MPdtSEIAIJl'n.` CHESTER B. ZUMWALT.