US 2918705 A
Description (OCR text may contain errors)
Dec. 29, 1959 a. 1.. PEARCE 99 9 LOG ASSEMBLY Filed June 14, 1954 2 Sheets-Sheet 1 7 f f.4. INVENTORu [rum Pearce I. L. PEARCE LOG ASSEMBLY Dec. 29, 1959 Filed June 14, 1954 2 Sheets-Sheet 2 INVENTOR. Irv/i2 L. Pearce United States Patent LOG ASSEMBLY Irvin L. Pearce, Broadbent, Greg. Application June 14, 1954, Serial No. 436,537
1 Claim. c1. 20-.5)
This invention relates generally to the production of veneer wood by the process of peeling selected logs in a veneer lathe. More particularly this invention provides a method and means for making complete use of logs which have defects which preclude such use under any prior art procedure.
In the production of veneer stock from logs by the peeling method, the log is held in a veneer lathe between centers and rotated against a stationary knife the full length of the log. Just ahead of the knife a pressure bar or a pressure roll, manipulated by a pair of compressed air cylinders, is carefully positioned as required to hold the log surface material in position for the desired peeling action of the knife. In fir log peeling a log length of eight feet with knife and pressure bar contact with the log for its full length is common practice. The total pressure of the pressure bar or roller on the log may be of the order of several thousand pounds. With peeling speeds of several hundred feet per minute the tangential pressure of the knife on the log will not only be large but will vary greatly and sometimes suddenly depending on the log structure. Centrifugal forces acting within the log itself during its rotation seem to be noticeable.
With a clear log without defects the peeling forces are of little concern, but many logs upon arrival at a veneer plant have one or more serious defects known in the art as pitch rings, pitch seams, shell rings, cracks, radial cracks, splits, wind shakes, etc. Any of these defects Weaken the log and in order that the log can be peeled on the lathe the parts of the log separated by the defects must be secured together.
Prior to the discovery and invention of the present method and means it was common practice to reinforce defective logs and even to reinforce green solid logs having a tendence to season check. In the prior art this reinforcement to withstand seasoning, handling, shipment,
and most of all, peeling, was done by driving into the ends of thelogs across the defects therein heavy steel fasteners of the general form of staples. Although necessary, this practice of using steel fasteners is undesirable and wasteful of both time and material because the steel fasteners must be removed prior to the time they would otherwise strike the knife of the veneer lathe. Bad timing in this respect has caused much damage to lathe equipment, and even if the steel fasteners are removed in time it is a difiicult task to remove them. In their removal by cutting out with axes, saws, etc., much lathe time and labor as well as good veneer Wood stock is lost.
The here first disclosed method of and means for preparing and peeling veneer logs is to provide for the purposeabove explained a reinforcing fastener or clip of a material that can be cut by the blade of the veneer lathe without harm to the blade and to provide a hand or power operated driver, then to drive into the ends of the log across its lines of weakness as many of the clips as are required, and finally to place the reinforced log in the veneer lathe and peel it as though it were a structurally, perfect log.
41% attention need be given the clips after insertion into the log for the lathe knife shears a clip of this invention just asit does the. wood surrounding ,the clip w r C leaving the sheared off piece of the clip embedded into the sheet of veneer.
In the practice of this invention it is necessary that the clips used be of a material adapted to the purposes for which it is used. For instance, it must be generally strong enough to withstand the peeling forces above described and yet free of such hardness or hard spots as would damage the lathe knife. In addition the clip must have the toughness to withstand the shock of being driven into the log and the hardness to maintain its driving edge. Less apparently but equally important the clip may not have the kind of resiliency that yields under a driving low to absorb the driving shock and then restore itself to its original shape before the next blow. Again it must have an ignition temperature high enough not to cause a fire later in the veneer drier and it must be of a material that will screen from the slurry from a paper pulp digester since the cores from veneer logs usually go to paper mills for processing into paper.
A principal object of this invention is to provide a veneer log having a defect therein requiring structural reinforcement before said log can be successfully peeled in a veneer lathe, at least one fastener driven into said log across said defect, said fastener being formed of material shearable by the knife of said lathe without damage to said knife.
A second object is to remove from the log peeling practice the hazard to life and property incident to the use of the prior art steel materials for reinforcing defective peeler logs.
A third object is to provide a method and means for achieving maximum recovery from a veneer log that has defects.
How these and other objects are attained is explained in the following description referring to the attached drawings in which Fig. l is a view in perspective of a preferred form of the clip or fastener of this invention.
Fig. 2 is a view in perspective of a bundle of the clips of Fig. 1 ready to be placed in a magazine of a driver therefor.
Fig. 3 is a fragmental sectional elevation of a driver showing the clips of this invention in the magazine thereof.
Fig. 4 is a view in perspective of the driver of Figs. 4 and 5 being used to lace up a defective log.
Fig. 5 is a conventionalized fragmental end view of a veneer lathe operating upon a log having defects laced with the clips of this invention.
Fig. 6 is a fragmentary perspective view of a log having defects laced with the clips of this invention, the log be ng shown in the condition of being processed into veneer.
big. 7 is a fragmentary perspective view of a log reinforced over a defect by a prior art use of a heavy steel staple.
Like numerals of reference refer to like parts in the several figures of the drawings.
Referring now to the drawings there is shown in Fig. 1 a clip or fastener 21 of a molded synthetic plastic material having overall dimensions of approximately 4 /2 inches long, 1 inches wide and V inch thick, tapered to form a relatively sharp edge at 22. The clip is symmetrically formed on each large face with four wide grooves 23 about inch deep thus forming on each face of the clip a relatively strong central panel 24, two symmetrically placed inner ridges 25 and two symmetrically placed end ridges 26. The lateral edges of grooves 23 or panel 24 and ridges 25 and 2-6 are normal to the cutting edge 22.
1 101927 midway between the ends of clip 21 andpgp;
mal to the flat surface thereof is for the purpose of receiving a bundling wire 28. As shown in Fig. 2 wire 28,
of malleable metal wire formed with a finger loop 29 on one end, is laced through the holes-27 of a plurality of clips 21'and the other end 30 of wire 28 is bent over to secure the clips. in a bundle 31 of convenientsize toform a load for the magazine 32 of the driver 33"of this iu-- vention. See Figures 3 and 4.
A preferred form of the driver of this invention shown therethrough from its forward edge 39 to its rear edge 1 40. Slot 41 is sized to receive slidably therethrough a 1 succession of the clips 21 and the clip propelling blade 37 of plunger 47. Clip magazine 32 is sized slidably to receive a bundle of clips 21. The interior of magazine 32 communicates with the fore and aft slot 41in body 34 to feed clips 21 from magazine 32 into driving position in 34 when plunger 47 is retracted and blade 37 clears the lower end of magazine 32. U-shaped channel 42, Fig.
4 is welded to body 34 to form a protective support for coil spring 43 secured at its ends to magazine pusher rod 44 to cause rod 44 to urge clips 21 successively from magazine 32 into driving position in slot 41. Rod 44 extends transversely across magazine 32 guided in a pair of L-shaped slots 45 formed through the lateral walls of magazine 32. To load the magazine, rod 44 is lifted up along the vertical legs of slots 45 to their tops and then rearwardly along the upper horizontal legs of slots 45 until rod 44 clears the vertical interior passage of the magazine.
Then a bundle 31 of fasteners is lifted by loop 29 of wire 28 and lowered into the magazine with' the sharp edges of fasteners 21 facing forwardly of the driver. Pusher rod 44 is then moved forwardly ,and downwardly in slots 45 until it comes to rest on the top of the bundle of fasteners where it is held resiliently by spring 43. While holding the fasteners in the magazine by holding down on rod 44 wire 28 is removed by pulling upwardly on terminal 29.
Body 34 is formed with a pair of spear points 46 ex tending forwardly therefrom for the purpose of engaging the surface of the log to secure driver 33 in place thereon when driving a fastener therein. This is a feature of the present invention and is required to prevent lateral movement of the driver relative to the fastener during the driving operation. Since the fastener is required to be shearable without damage to the lathe knife it necessarily is not strong enough to guide the driver during the driving operation.
Secured at one end to driver body 34 by cap screws as shown are steel straps 52 the other ends of which are welded to a steel collar adapted slidably to receive the cylindrical barrel of pneumatic hammer 49. Adriver steadying handle with a supporting hand knob 56 extends horizontally to the left from the collar to which it'is welded.
Hammer 49 is equipped with a trigger or air valve handle which when pressed forward by the operators thumb releases air under pressure to the hammer which then operatesin the well known manner to drive clip 21.
A carrying or supporting handle or bail 62 for the combined driver and air hammer shown in Figure 4 is formed of a round steel V-shaped rod with its downwardly-extending ends reversely turned inwardly and welded to the straps 52 as shown. Bail 62 is positioned at approximately the fore and aft balance position of the combined driver and hammer and is useful not only forcarrying the apparatus from place to place but also as shown in Figure 4 for counterweighting the apparatus with a balancing weight 63 attached to bail 62 by a cable 65 termimating in a loose hook 64 through which bail 62 can slide as the driver is rotated on its driving axis while being conventionalized end view in partial section of a log 66 supported on a lathe arbor 67 with an arbor end flange 68 equipped with heavy spear points 69 for engaging the log 66. Log 66 is shown to be defective in that it has a radial crack 70 and a wind shake 71 both longitudinal thereof and appearing at theends of the log. As shown the weakened condition of the log has been overcome by having multiples of the fasteners 21 across the defects. The log is shown as being peeled to veneer .wood 72 by rotating the log counter-clockwise against the knife 73 of the lather while the surface of the log ahead'of the knife is firmly controlled by a roller 74 mechanically rotated at a selected speed while being held down by a pressure bar 75 manipulated into the position selected for the best log peeling operation by a pair of air cylinders 77 schematically indicated in Fig. 5 to be con--- nected to bar 75 by piston rods 76. Knife 73 is seen to" be supported in a knife bar 78 and adjustable therein by adjusting screws 79.
Since the lathe itself is no part of this invention, its
construction and operation will not be described further. Literature on this subject is readily available. See the paper entitled Equipments in Rotary Veneer Cutting" by H. O. Fleischer presented at the Third Annual National Meeting of the ForestProducts Research SocietyatiGrand Rapids, Michigan, May 2, 3 and 4, 1949, to-' gether with the bibliography included therewith. But w note that in peeling the log to veneer in Fig. 5, the lathe 1 knife has just cut a slice 21-a from the fastener 21-b.
In Fig. 6 is shown in perspective a fragmental view of a partially peeled log 80 in .a lathe. The log is cracked as shown at '81 and reinforced by fasteners 21, the outermost of which is shown after a section has been sheared L off by the lathe knife.
In Fig.7 is shown in perspective a fragmental view of a log having a defect in the form of a split 82 and showing the prior art method of reinforcing a defective I log by the insertion of one or more large steel staples. With this older method of reinforcing the lathe must be stopped before the lathe knife encounters the staple and the staple must be chopped or sawed out with a resultant. waste of time and material. Failure to remove the staple in time results in serious danger to life and serious damage to the lathe.
In Fig. 4 the driver of this invention is shown processing a defective log with the fasteners of this invention.
From the several figures of the attached drawing and the descriptions thereof, it is seen that this invention includes a new and useful log assembly formed by means and methods shown and described and seen to be the successful embodiment of the aforementioned principal object hereof which I now claim and define as follows:
In a veneer log having a defect therein requiring structural reinforcement before said log can be successfully peeled in a veneer lathe, at least one fastener driven into said. log across said defect, said fastener being formed of material shearable by the knife of said lathe without damage to said knife.
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