CA2275449A1 - A log chipping head - Google Patents

Abstract

A log facing chipper head used to process logs into cants. The chipper head is outfitted with a knife and knife holders, the knives consist of a rounded cutting profile on each corner of the knife. These profiles Ramp the knife into the log with no fiber tear out. A short knife follows behind the long conical knife cutting on a post-cutting plane to impart a final finish on the cant.

Description

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Patent Application of Michael Lindsay Capp For A log-chipping head Background -- Field of Invention This invention relates to large Log Chipping heads with attached knives and knife holders, used to process tree logs into a rectangular shape referred to as (cants).
Background -- Description of Prior Art Brief description A chipping head is used to process wood in the form of chips from the sides of a log and in the process leave a flat smooth finish, this is accomplished by attaching several large knife holders, which use a sharp knife. To a large hub driven by a power source.
The chipping heads (usually 2 a left and a right) are generally set up on slides or shafts this enable them to be positioned in or out to accommodate different diameters of logs. As the log moves towards these heads in a horizontal position The conical chipper heads move to a predetermined position calculated by scanners, which have calculated the optimum position of the heads for the best board finish and chip recovery. Heretofore many chipper heads have been devised for holding the arrangement of the long knifes and short knifes.
The long knife is situated on a conical plane sweeping in a forward angle, This long knife process's most of the log surface face into a marketable chip, the small knife which is situated directly below but with the knife edge positioned on a vertical plane is used cut off a chip and to provide a decent finish, The surface of this cant face account for one of the board faces after the cant has finished all primary-manufacturing processes.
In the conical head chippers as of present U.S. Pat. No 5,623,977 U.S. Pat.
No. 5,271,442, The short knife is installed in a vertical fashion with the edge of The blade in a position facing forward then the long knife Which cuts in a conical plane is mounted and slid down the holder to abut onto the top to the Short knife. With both leading edges contacting each other As a result of this configuration the surfaces finish has suffered because of the next to impossible task of getting the two Knife-edges to come together in a precise manner, Even if the components could be made extremely precise and the maintenance perfect, as the chipper head is processing logs small wood fiber get in-between the two knives and starts to push against each other. This results in the long knife creeping up the holder exposing the edge of the long knife, which proceeds to scour the cant surface.
The object of the invention is to provide a pair of knife holding structures, which hold a double-edged knife with profiled cutting edges on all Four Corners. These improved structures stand independent from each other and are there fore easily adjusted.

Objects and Advantages Accordingly, several objects and advantages of my invention are to provide a superior knife holder that can be used in chipping a surface finish on cants.
(Tree logs which are squared up on two or all four sides) with very little maintenance and provide a high quality of finish with consistent results.
This is accomplished by a new design, which uses a new knife profile and locating configuration with the knife holders to accomplish this.
The idea consists of a pair of knife holders with the large knife holder in front of the small knife holder, with the small knife holder located in a post-cutting plane on the main hub This totally eliminates the torn fiber problems associated with present chipping heads. The long knife now consists of two opposing cutting faces with a twin V notch for locating the knife on the holder this ensures that the knife will be kept fixed to the holder with absolutely no chance of movement.
The profile of the long and short knife both now have a cutting profile on each corner of the knife, this cutting profile extends from the face and around to the back of the blade.
This feature on the knife allows the long knife to cut chips and impart a finishing cut on to the surface of the cant with very little maintenance needed for a critical fit up between the short and long knife.
Still further objects and advantages will become apparent from a consideration of the ensuing description and accompanying drawings.
Brief Description of the Drawings Fig. 1 is a Primary long knife holder Fig. 2 shows Secondary small knife holders Fig. 3 shows profile of the knife used Fig. 4 is a perspective view of the over all chipper head with all of the knife holders in place Fig. 5 is a large hub with milled flats?
Fig. 6 shows a view of the log being processed.
Fig. 7 is a large round disk attached to the chipper hub Reference: Numerals primary long knife holder 11 drilled and taped hub 12 long knife 13 small knife 14 knife clamp six fasteners 16 milled recess 18 counter knife secondary (small) knife holder 22 square base 24 knife holder 26 keyway 28 small knife clamp knife profile 32 two cutting edges 34 milled V grooves 36 profiled cutting corners 38 main circular hub with flats anvil 42 hub with fasteners 44 tree log 46 four fasteners Preferred Embodiment -- Description Fig 1 is a primary long knife holder 10 used on conical head style wood chippers the parts consist of a primary knife holder to hold the long knife 12 and a knife clamp 14.
With four fasteners 46, A milled recess 16 in the upper flat portion is used to hold the counter knife 18 and provide Adjustability.
Fig 2 shows the secondary (small) knife holder 20 used to put the final finish on the cant this holder comprises of a square base 22 with a knife holder 24 which can be adjusted forward and back to set up a common finishing plane.
The small holder utilizes a keyway 26 or dovetailed recess to keep the holder in a rigid position on the cutting plane, a small knife 13 clamp 28 is used to hold the small knife in place.
Fig 3 shows a close up view of the knife 30 edge profile this consists of a knife with two cutting edges 32 and milled V grooves 34 on the under side to mate with the counter knife. The knives are ground with profiled cutting corners 36 in the form of a radius.
This extends from the front of the knife and curves around meeting with the back of the blade, this profile Is unique to the design in that it ramps the knife into the wood leaving no Knife edges to scour the surface of the cant.
Fig 4 is a perspective view of the entire knife holders and knives in place and on their cutting plane. These components comprise of a main circular hub with flats 38 milled on it to fasten both of the knife holders with six fasteners 15. On the very front of the hub a anvil 40 as it is sometime called is fixed to the hub with fasteners 42, it is used to control the tree log 44 a$ it I$ ~gin~
~~p~~~sed by the conical side heads.
Fig 5 is a large hub drilled and taped 11 to attach the large and small knife holder bases and the round disk called the anvil. 40 Fig 6 the view of a log cant as its being processed from a Arial view. Only one side head is shown for visual clarity.
Fig 7 is a round disk used to control the log cants while they are traveling through the chipper heads.

Preferred Embodiment -- Operation Please refer to the drawings, In (fig 4) the two conical side heads are mounted in a fashion such as they both oppose each other and are easily adjusted in and out to accommodate different log diameters. Only one side is shown in the view. The large hubs 38 have flats milled on them to accept the primary long knife holders 10 they are drilled and taped 11 (fig 5) so that these components can be changed out when in need of repairing. In (fig 4) the long knife 12 can be referred as the primary cutting blade and the small knife 13 as the secondary cutting blade. Both knives have the same rounded cutting profile 36 (fig 3) on all four corners this enables the knife to be rotated and used in four knife changes before sharpening this will cut down on maintenance and knife cost. These large knife holders 10 are bolted to the hub with fasteners 15 using the counter bored holes in the bases.
The milled recesses 16 (fig1) on the top surface structure of the large holders are used to accept the counter knives18. These counter knives are mounted to the large holder with three small fasteners, which mount through the slotted holes 17 on the counter knife 18 and thread into the large knife base 10. This allows the counter knife to be moved in and out to adjust the cutting depth of the knife 12 this is important so as that all knives cut on the same plane. Mount the long knife 12 in place using the milled V notch 34 on the counter knife 18 which corresponds with the double V recess in the knife 34b {fig 3) This double V notch holds the knife from moving forward or backwards due to the wedge shape of the double V shape. In (fig 1) the knife is clamped in place with the large knife clamp 14 and four fasteners 46. As the large knife clamp is tightened down the knife becomes very secure due to the wedging action between the knife clamp 14 and the counter knife 18.
Referring to (fig 4) the small secondary knife holder 20 is setup behind the large knife holder 10. The cutting face on the short knife is situated on a vertical plane, this short knife must be designed to cut on a smaller circle than the long knife. This is what is called a post cutting action, Meaning that the long knife 12 is doing most of the cutting before the small knife 13 does.
This is regulated by the manufactured height of the holder bases.
Refer to the drawing (fig 6) for a more detailed view of this operating principal.
As the tree log enters the chipper head the long knifes 12 starts to profile the round Surface of the log 44 into a flat face; this is accomplished with no scouring on the surtace, as there are no sharp corners. This is because the new profile which has a curved cutting profile 36, which extends around from the surface of the knife blade and meets the knife base, this ramps the knife into the wood exposing no Sharp knife edges to the wood. As the log proceeds further through the chipper head the secondary knife 13 (small Knife) takes of a finishing cut which is also a marketable chip. This small knife is also vamped into the wood with a profiled cutting corner 36 (Fig 3) In the preferred embodiment these knives are both independent of each other this makes this chipping head design almost maintenance free with very little work to set up. The operating principal is quite simple use a dial indicator to dial all installed long knives 12 to -. 025 behind rotating disk called anvil 40 (fig 7)(Fig 4) Install all short knives in holders and torque up to spec and then dial these knives to .025 over disk faces 40 using the adjustable knife hold~~~ 2~ to accomplish this.

Conclusions, Ramifications, and Scope Accordingly, it can be seen that the knife with the cutting profile on each edge and situated as they are on the main hub makes for a low Maintenance and user friendly design. The cutting profile of the knife enters the wood with little or no resistance and then as the knife passes along the face of the log imparts a near perfect finish with no fiber tear out. This is inherent of the curved cutting edge of the knife.
Although the description above contains much specificity, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention.
Various other embodiments and ramifications are possible within it's scope.
For example, any number of configurations exist with the placement of the short knives in relation of the long knife there are different angles of attack on the log with this knife style that can be tried the angle of the short one in relation to the long knife.
There is just a plethora of options to try.
Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.

Claims (3)

1. Claim 1 A multitude of chipping head knifes and holders fixed to a large hub comprising of a primary knife holder a secondary knife holder a knife support called a counter knife which has a profiled end to mate with the knife this counter knife sits in a milled recess to allow for adjustment with out side to side movement.
   a secondary knife holder which houses a small finishing knife, this holder is adjustable in a milled key way or dovetail on the milled base to allow for precise adjustment.
   This secondary holder is independent from the primary knife holder and is adjusted independently from the primary knife holder with no interference from each other.
2. Claim 2 a chipping knives which consist of a rounded cutting profile on each comer of the chipping knife this profile Starting on the face of the knife and proceeding around and meets the base of the knife each and all Four Corners of the knife are profiled in this manner.
   a knife profile which ramps the cutting edge of the knife into a log.
   a knife which can be rotated so that all four cutting profiles can be utilized.
3. Claim 3 A chipping head outfitted with a large primary cutting knife and holder with the long knife located on a conical plane this is preceded by a secondary knife holder with the short knife situated in a vertical cutting plane in relation to the log.