Claims:
I claim
1. A portable timber milling jig comprising stand means positioned relatively adjacent the ends of said jig for receiving therebetween in spaced relation a log to be sawn, said stand means including means for clamping the log at the ends thereof to hold it rigid during the sawing operation, rail means extending between and connected to said stand means, jig carriage means movably supported on said rail means for longitudinal sliding movement therealong, said carriage means being provided with means for mounting a saw at a desired angle to the vertical, whereby said jig carriage means as it travels longitudinally along said rail means makes a longitudinal cut at the desired angle in the log.
2. The portable timber milling jig of claim 1 wherein said means for clamping the log comprises a number of parallel prongs at the end of an adjustable arm supported by said stand means.
3. The portable timber milling jig of claim 2 wherein said adjustable arm has brackets thereon to receive two angled legs which act to stabilize the stand means.
4. The portable timber milling jig of claim 1 further including means associated with said stand means for vertically adjusting the height thereof.
5. The portable timber milling jig of claim 1 wherein said rail means comprises a beam having a hollow square cross-section, the diagonals of the square being approximately horizontal and vertical.
6. The portable timber milling jig of claim 5 wherein said jig carriage means comprises upper and lower right-angled sections, each of the four inner faces supporting bearing means which contact a corresponding face on the beam for smooth rolling movement of the carriage means along said beam.
7. The portable timber milling jig of claim 6 further including a pair of brackets being mounted on the outer faces of said lower section of said carriage means, and an extension arm slidably mounted in said brackets for supporting said saw.
8. The portable timber milling jig of claim 7 wherein said extension arm has at its outer end a saw receiving clamp screwed thereon, said clamp being provided with jaws for clamping the handle of said saw.
9. The portable timber milling jig of claim 8 wherein said extension arm has a series of holes therein for receiving a dimensioning gauge for ease of repositioning the extension arm and thus said saw relative to the jig carriage means.
10. The portable timber milling jig of claim 8 further including damper means mounted on said extension arm to prevent grabbing of the saw in the log.
11. The portable timber milling jig of claim 1 wherein said means for mounting said saw comprises an extension arm supported on said jig carriage means having at its outer end a saw receiving clamp.
12. The portable timber milling jig of claim 11 wherein said extension arm has a series of holes therein for receiving a dimensioning gauge for repositioning said extension arm and thus said saw relative to the jig carriage means.
13. The portable timber milling jig of claim 12 further including damper means mounted on said extension arm to prevent grabbing of the saw in the log.
Description:
This invention relates to improvements in sawing timber, and in particular to a portable timber milling jig facilitating the sawing of logs into sawn timber at the location where the tree has been felled thereby eliminating the necessity to haul the logs to a conventional saw mill for processing.
The advantages of sawing the logs where the tree has been felled include the speed of total operation due to the elimination of handling and hauling of logs, the reduction in capital cost of equipment required to process the timber and the ease with which the man-on-the-land may quickly acquire the timber he requires for building purposes and the like.
SUMMARY OF THE INVENTION
The object of the present invention is to provide jig means which assists in the reduction of felled logs to sawn timber.
It is a further object of the present invention to provide means whereby a chain saw or the like may be used to make two series of parallel cuts in a felled log, the series being at right angles to each other, whereby sawn timber is obtained.
Accordingly, the present invention provides a portable timber milling jig comprising stand means to be placed at either end of a log to be sawn, said stand means including means for clamping the log at either end to hold it rigid during the sawing operation, rail means connected between the stand means at either end and jig carriage means supported by and adapted to move along said rail means, said jig carriage means having means whereby a chain saw, a circular saw or a reciprocating saw may be mounted thereon at any desired angle to the vertical, so that, as said jig carriage means travels along the rail means from one end of the log to the other, said chain or circular saw may cut a longitudinal cut at a given angle in the log.
Adjustment means may be provided on the jig carriage means, the means mounting the chain or other saw, and on the stand means whereby the height of the rail means, the angle of the chain or other saw and the depth and height of the chain or other saw cut may be adjusted as desired. Thus, by appropriate adjustment, it is possible to cut a series of parallel cuts at a given angle in the log, the height of the saw being adjusted between each traverse of the saw along the rail means. Then, by turning the saw through 90°, it is possible to cut another series of parallel cuts so that the log is then sawn into a number of rectangular sectioned lengths of sawn timber.
In order to avoid having to adjust the clamping means between traverses, the depth of the saw cut may be adjusted so that it does not cut completely to the end of the log, the end portion of the log acting to hold the log together during further sawing of the log.
In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings wherein :
FIG. 1 is a perspective view of the portable timber milling jig of the present invention;
FIG. 2 is a front elevation of the portable timber milling jig of the present invention;
FIG. 3 is a plan view, along the sectioning plane II -- II of FIG. 2;
FIG. 4 is a cross-sectional view along the plane III -- III of FIG. 2;
FIG. 5 is an end elevation of FIG. 2; and
FIG. 6 is an end elevation of damper means.
A hollow square-cross-sectioned beam 11, set so that its diagonals are approximately horizontal and vertical, acts as the rail means along which runs carriage 12, with its adjustable arm 13, supporting the chain saw 14. Either end of the log 15 to be cut, is held by clamping points 16 at the end of arm 17 supported by vertical stands 18 which, by means of beam support clamps 19, also support beam 11.
The vertical stands 18 which are about 18" from the end of the log to allow clearance for the saw, are adjustable in height, having spring loaded adjustable leg 20 for quick setting of the height. Stop screws 21 and 22 prevent the leg 20 either from dropping out of stand bracket 23 or from fouling against beam support clamps 19 respectively. Stabilizing legs 24 which slide through brackets 25 on arm 17 extend at an angle on either side of the stand 18 to provide anti-roll extra rigidity.
A beam support clamp 19 has a fixed jaw 26 welded to the top of the stand. Both the fixed jaw 26 and hinged jaw 27 are formed with two faces at 45° to the horizontal to include a right-angle so that when they close about the square-sectioned beam 11, they grip it therebetween. A quick release catch, incorporating a handle 28, holds the two jaws together around the beam 11.
The carriage 12 consists of upper and lower right-angled sections 29 and 30 respectively which are bolted together by bolts 31.
At either end of the carriage 12, are located four ball bearings 32, providing running contact between each of the four faces of the beam 11 and of the carriage 12. By turning handle 33, which drives a friction wheel via a gear reduction box (not shown), the carriage 12 may be moved along the beam 11.
Bolted to both the lower faces of the carriage 12 are brackets 34 through one of which the adjustable arm 13 may slide to the desired setting and then be locked in said setting. The adjustable arm 13 consists of a beam having a series of holes 35 drilled therein at regular intervals, said holes being adapted to receive dimensioning gauge 36 which acts as a stop to give the desired width of cut.
To the lower end of the arm 13 is screwed the saw receiving clamp 37 which has jaws 38 to receive the rod handle of the chain saw 14. As the adjustable arm 13 is supported parallel to a face of the carriage 12 and so to a face of the beam 11, it is supported at an approximate angle of 45° to the vertical. Thus the blade of the chain saw 14 is also supported at an angle of 45° to the vertical, and so a cut made thereby is also at 45° to the vertical.
Damper means as shown in FIG. 6 may be attached to the lower end portion of arm 13 adjacent the saw receiving clamp 37 at the end thereof, to prevent the saw from vibrating in the log. The damper means consists of a square section 38 held on three faces by screws 39 to arm 13, screws 39 also holding inner and outer rings, 40 and 41 respectively, together. A spring loaded pawl 42 is located between the inner ring 40 and section 38. Tubular section 43 is welded to outer ring 41 so that adjustment arm 44 is free to slide therein. Adjustment arm 44 has a pointed end 45 of soft metal, the arm 44 being adjusted in length so that end 45 touches the log 15. Should the saw tend to pull into or "jazz" the log, thus also pulling the pointed end 45 into the log, the ratchet on pawl 42 grabs preventing such movement, the coil spring 46 on outer ring 41, after a predetermined tension, coming into operation to return the outer ring and pawl to their original positions, this return thus dampening the movement of arm 13 and so of the saw itself.
In use, the tree to be sawn, is felled, an appropriate length of the trunk selected and a set of clamping points 16 driven into the center of the larger end of the log. The vertical stand 18 is then placed so that it is slightly out of vertical. The second set of clamping points 16 is then driven into the smaller end of the log and again the vertical stand erected, also slightly out of vertical with its upper end away from the upper end of the stand at the other end of the log. Each vertical stand is approximately 14 inches from an end of the log to allow clearance for the saw. The beam 11 is then mounted approximately horizontal, in support clamps 19 with the carriage 12 adjacent one support clamp. As support clamps 19 fasten around beam 11 they draw stands 18 into the vertical position, at which point, the adjustable leg 20 and stabilizing legs 24 are placed in position. The adjustable arm 13 is then raised, by sliding through one of brackets 34, until the chain saw blade 39 is at a height sufficient to cut a top slice from the side of the log. The damper means are adjusted so that pointed end 45 touches the log. The adjustable arm 13 is then locked in position, the chain saw 14 set in motion and the carriage 12 guided, by handle 33 along the beam 11, so that the top slice is cut from the log.
The dimensioning gauge is then set so that it corresponds to the desired width of the timber to be cut, the arm 13 released to slide down the distance corresponding thereto and then again locked in position and another traverse of the carriage 12 along the beam 11 produces a second cut in the log parallel to the first. Dependent on the size of the log and on the desired width of timber to be obtained, a number of similar cuts may be made.
The arm 13 is then released from the first bracket 34 and slid into the second bracket 34 at right angles to the first so that the saw arm may be reversed thereon in order to make another series of parallel cuts, this time at right angles to the first series.
When sufficient cuts or traverses have been made, the jig may be easily dismantled by releasing the clamps at the top of stands 18 and lifting the beam 11 free.
The jig ends are then removed from the log ends which are either cut off or the cuts extended therethrough to release the sawn timber. The jig may then be transported to another location.
Although, as described above, the sawn timber is of rectangular cross-section, other sections may be sawn by adjusting the angle of the saw cut -- preferably by the use of a wedge to alter the angle of the arm 13.
If desired, the length of the beam 11 may be extended by fixing thereto further lengths of the same cross-section so that any length of log may be sawn. Other beam cross-sections may also be used, the carriage wheels being adjusted appropriately so that the carriage and saw are adapted to be moved steadily along the beam.
The advantages and ease with which timber can be sawn will be seen from the above description, especially for the farmer or like who requires only a limited amount of sawn timber. In addition the timber is not liable to be infested with borers or the like as it is removed shortly after felling and not left for any length of time.