US2694422A

US2694422A - Log turner for sawmills

Info

Publication number: US2694422A
Application number: US261982A
Authority: US
Inventors: Doty Lester Earl
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-12-17
Filing date: 1951-12-17
Publication date: 1954-11-16
Anticipated expiration: 1971-11-16

Description

Nov. 36, 1954 L. E. DOTY 2,694,422

LOG TURNER FOR SAWMILLS Filed Dec. 17, 1951 3 Sheets-Sheet l Nav. 16, 1954 L. E. DOTY LOG TURNER FOR SAWMILLS 5 Sheets-Sleet 2 Filed Dec. 17, 1951 LESTER E. DOTY A Trurevvav Nov. 16, 1954 1.. E. DOTY 2,694,422

LOG TURNER FOR SAWMILLS Filed Dec. 17, 1951 5 Sheets-Sheet 5 United States Patent Q LOG TER FOR SAWMILLS Lester Earl Doty, Portland, Oreg.

Application December 17, 1951, Serial No. 261,982

Claims. (Cl. 143-97) This invention relates generally to wood working machinery and particularly to a log turner for sawmills.

The main object of this invention is to construct a log turner which will use the travel and inertia of the saw carriage to turn a log preparatory to taking another cut.

The second object is to reduce the number of man hours required in the sawing operation.

The third object is to produce a log turner which will be simple and inexpensive to construct, smooth in operation and not easily rendered inoperative from reasonable use.

I accomplish these and other objects in the manner set forth in the following specification as illustrated in the accompanying drawings, in which Fig. l is a diagrammatic plan view of the device showing in full lines the log carriage position at the time of sawing and showing in dotted lines the position of the log carriage at the end of the return travel. The position of the log at the loading point is also indicated in dotted lines.

Fig. 2 is a vertical section taken along the line 22 in Fig. 1.

Fig. 3 is a diagrammatic plan view showing the bell crank levers and their relation to the carriage and actuating pin.

Fig. 4 is a section taken along the line 44 in Fig. 1, and illustrates the manner of raising the actuating pin.

Fig. 5 is a section through the valve for controlling the loading arms located on the loading bunk.

Fig. 6 is a fragmentary perspective of the loading bunk.

Fig. 7 is a fragmentary transverse section through the carriage way illustrating the transfer of the log from the carriage to the loading bunk.

Fig. 8 is similar to Fig. 7 but shows the first step in sliding the log from the loading deck or bunk onto the saw carriage.

Fig. 9 is similar to Fig. 8 but the log is now entirely on the carriage and the pusher arms ready to return to rest.

Fig. 10 is an end view of a log showing the purpose of turning its cant.

Like numbers of reference refer to the same or similar parts throughout the several views.

Referring in detail to the drawing, in order to more quickly understand the purpose of this invention, there is shown a saw log from which it is desired to cut a timber 21 by removing the slabs 22 by sawing the various cuts 23. See Fig. 10.

The invention involved herein lies in the means for turning the cant so as to present the desired side to the saw.

There is shown a log carriage 24 whose wheels 25 roll on the tracks 26 mounted on the sub-floor 27 disposed below the level of the saw deck 28. Under the deck of the log carriage 24 are mounted a plurality of bellcrank levers 29 and 30, one end of all of which is joined by a pullrod 31 whose action is resisted by a tension spring 32 attached to the carriage 24.

The bellcrank 29 has one longer arm 33 which projects beyond the side of the log carriage 24 and contacts the actuating pin 34 at the near end of the walk way 35, the purpose of which will be explained later.

Along the saw side 36 of the log carriage 24 is mounted a rock shaft 37 on which are mounted the segment arms 38 from which project the log turning arms 39 whose ends 40 rest on the U-beam 41 which also supports the pivot pins 42 of the bellcrank levers 29 and 30.

Patented Nov. 16, 1954 A chain connects each segment arm 38 to each bellcrank 29 and 30. On the log carriage 24 are the knees 43, which are in common use and are manually positioned to back up the cant or log 20 on the carriage 24.

In Fig. 6 is shown the bunks 44 of the log deck 45, which is hinged on one side to the shaft 46 and supported on the opposite side by the cams 47, which are mounted on the rock shaft 48. Loading arms 49 are also mounted on the shaft 48 and both the earns 47 and arms 49 are secured to the shaft 48. A lever 50 is secured to the shaft 48 and is operated by the pressure cylinder 51 which is connected by the pipes 52 and 53 to the control valve 54, shown in Fig. 5, having a pressure inlet pipe 55 and a return pipe communicating with the supply tank (not shown).

On the saw deck is disposed a foot operated plunger 56, which is connected to a lever 57 supported between its ends by a fulcrum 58 attached to the saw deck 28. See Fig. 4. The end 59 of the lever 57 is connected to the actuating pin 34, which is slidable in a vertical direction and it stands in the path of the lever 33.

The operation of the log turner is as follows: Assuming that a log has been placed on the log loading deck 45, the operator moves the control lever 60 of the valve 54 which, by admitting pressure to the cylinder 51, causes the loading arms 49 to move upwardly, as shown in Fig. 8, and finally to the position shown in full lines in Fig. 9, in which the log or cant 20 has been slid across the bunks 44 onto the carriage 24 against the knees 43. The purpose of the earns 47 is to raise the bunks 44 above the deck of the carriage 24 when loading and to lower the bunks 44 below the top of the deck 24 when unloading. The sawyer then moves the entire log carriage 24 past the saw 61 by means of the cables 62 and 63 through a cable winding mechanism (not shown). When the cut is made and the slab 22 or cut-off board or plank falls away from the cant 20, the log carriage 24 is returned to the point of loading. Before it reaches the end of the return travel, the operator depresses the plunger 56, which causes the actuating pin to rise and engage the arm 33, after which a further movement of the carriage 24 will move the lever 33 to the position shown in dotted lines in Fig. 3, causing the arms 39 to rise to the position shown in Fig. 7; that is, to turn the cant through onto the bunks 44. Thus, it can be seen that the cant is turned as it is unloaded and slid when it is moved onto the log carriage 24 unless the log is still round, in which event it might roll when loading.

No attempt has been made to show those features common to all sawmills, such as holding dogs and other details, the use of which is well understood by those familiar with sawmill construction.

I claim:

1. A log turner for sawmills having in combination a log carriage, log turning arms mounted on said carriage, an actuating pin vertically movable in the path of said carriage and a bellcrank lever mounted on said carriage having one end operatively connected to said turning arms and the other end intersecting said actuating pin when said pin is in a raised position whereby the inertia of said carriage will actuate said turning arms.

2. A log turner for sawmills having in combination a log carriage, log turning arms hinged to said carriage along the saw side thereof, means for raising said arms from horizontal to vertical positions, a retractible stop in the path of said carriage and a bellcrank lever mounted on said log carriage, one end of which is engageable with said stop and the other end of which is operatively connected to said arm raising means whereby the movement of said carriage against said stop will raise said log turning arms.

3. A log turner for sawmills having in combination a log carriage, log turning arms hinged to said carria e adapted to swing in planes normal to the travel of said carriage, bellcrank levers mounted under said carriage, each of which levers has one end attached to one of said log turning arms, the other end of each bellcrank lever being joined to the corresponding end of the other bellcrank levers, a spring for urging said joined ends in one direction and a vertical movable stop along the path of said carriage adapted to engage one of said bellcranks and operate all of them when said log carriage is moved toward a loading position while said stop is in a raised position.

4. A log turner for sawmills having in combination a track, a log carriage on said track, a saw mounted alongside one end of said track, loading bunks disposed at the opposite end of said track, cams for raising the ends of said loading bunks above the level of the log carriage when loading, loading arms associated with said loading bunk, an actuating shaft secured to said arms and bunk raising cams, means for operating said shaft, log turning arms pivoted on said carriage, each turning arm having a curved chain arm concentric with the pivot of the turning arm, a bellcrank lever mounted on said carriage transversely opposite each chain arm, a chain connecting one end of each bellcrank to its corresponding chain arm, a spring urged pull rod connecting the opposite ends of all of said bellcrank levers, one of said bell crank levers having one of its arms projecting beyond the other bellcrank levers and a manually operable, vertically movable stop in the path of said projecting arm end, whereby the raising of said stop will cause it to engage said projecting arm and actuate said turning arms when said carriage is moved to a loading position in a manner to move said turning arms to an upright position or to allow said turning arms to remain in horizontal positions if said stop is not raised.

5. In a sawmill comprised of conventional track mounted carriage with a log loading means at one end of the track and a saw at the other end of the track in combination with a plurality of log turning arms mounted on said carriage, each log turning arm having a bellcrank lever mounted transversely therefrom on said carriage, said bellcrank levers having a joining spring urged connecting rod, one of said bellcrank levers having its rod end projecting from said carriage, a movable stop on the deck of said mill alongside of the loading end of said track with means for moving said stop in the path of said projecting arm whereby the inertia of said carriage actuates the log turning arms when said stop is moved into the path of said projecting arm.

References Cited in the file of this patent UNITED STATES PATENTS 1 Number Name Date 362,826 Ferris et al. May 10, 1887 448,593 Simonson Mar. 17, 1891 640,501 Thomas Ian. 2, 1900 832,578 Huntington Oct. 2, 1906 1,248,432 Krebs Nov. 27, 1917 1,623,854 Rooney Apr. 5, 1927 2,484,362 Weber Oct. 11, 1949