US2588484A

US2588484A - Mechanical off-bearing means

Info

Publication number: US2588484A
Application number: US172132A
Authority: US
Inventors: George W Charters; Bernard H Michels
Original assignee: Crown Zellerbach Corp
Current assignee: James River Corp of Nevada
Priority date: 1950-07-05
Filing date: 1950-07-05
Publication date: 1952-03-11
Anticipated expiration: 1969-03-11

Description

March 11, 1952 G. w. CHARTERS EI'AL 2,583,484

MECHANICAL OFF-BEARING MEANS 2 SHEETSSHEET 2 Filed July 5, 1950 'ENTORS GEORGE w. CLIIXVRTEEESS BERNARD H. M ICH ATTOR N EY Patented Mar. 11, 1952 NEECHANICAL OFF-BEARING MEANS George W. Charters and Bernard H. Michels, Camas, Wash, assignors to Crown Zellcrbach Corporation, San Francisco, Calif., a corporation of Nevada Application July 5, 1950, Serial No. 172,132

3 Claims. 1

This invention relates to the sawing of slabs from the sides of logs and an object of the invention is to provide mechanical off-bearing means by which the slab, as it is being sawed from the log, will first be partly supported to reduce the tendency to split off from the log before the sawing is completed, and then, when it is entirely separated from the log, can be controlled and directed and moved rapidly and easily into a desired position with the flat side down.

A further object of the invention is to provide additional and supplemental off-bearing means to be used in conjunction with slab-positioning rolls, and, specifically, with the particular type of positioning rolls described in U. S. Patent No. 2,468,036, issued April 26, 1949.

The construction and mode of operation of our improved mechanical off-bearing means will be readily understood from the following brief description. In the description reference is made to the accompanying drawings in which:

Fig. 1 is an elevation of the device comprising the off-bearing means and showing also the forward end of the log carriage with a log mounted thereon and a slab in the act of being cut from the log, a portion of the mechanism for the offbearing means being broken away and shown partly in section for the sake of clarity; and

Fig. 2 is a corresponding plan view.

The log L from which the slab S is being out by means of the usual band saw (portion of the band saw being indicated by It] in Fig. 1), is supported on a moving carriage l l of well-known type, and the log is held in position by the customary adjustable knees l2 and dogs (not shown), as the carriage moves the log longitudinally in the direction indicated by the arrow in Fig. 2.

A plurality of slab-positioning rolls [3, having conically-shaped and enlarged ends adjacent the side of the carriage, are driven in unison from a shaft I4 with which they areconnected by suitable pairs of gears and [6. Such slab-positioning rolls are described in detail in U. S. Letters Patent No. 2,468,036, previously mentioned and need not here be further described.

been sawed. One of the purposes of our device is to provide some support for the slab at this period to reduce the tendency to split off from the log. When the slab is entirely separated from the log it drops onto the rolls l 3 at first in some such position as that indicated by the broken line poof the housing 3|.

sition S in Fig. 1. The purpose of our mechanical off-bearing means then is to facilitate the sliding of the slab into the desired final position on the rolls l3, that is with the sawed face of the slab down.

A swinging frame, including a horizontal platform 1! which is rigidly attached at one end to a vertical member I8, is hinged to an upright post l9 by suitable hinges 20, as shown in Fig. 1, so as to swing in a horizontal plane. A pair of parallel vertical uprights 2| are rigidly mounted on the free end of the platform I], and tie rods 22 connect the upper ends of these uprights 21 with the top of the member [8, thus forming a more rigid structure. This structure or swinging frame is also reinforced by a pair of triangularshaped braces 23 extending from the platform IT to the upright member l8. A pair of wheels 2d,

carried in suitable mountings attached to the underside of platform I1, act as an additional support for the free end of the swinging frame. These wheels 24 are arranged so as to roll on a curved horizontal track 25 which in turn rests on a stationary base block 26.

While the swinging frame is free to swing in one direction its swing in the opposite direction is limited by a stop block 21. A rope or cable 28, attached to the swinging frame passes over a pulley 29 and a weight W is attached to the other end of the cable 28 and acts to bring the swinging frame back into position against the stop block 21. Suitable cushioning means (not shown), may be provided on the stop 21, or on the adjacent side of the swinging frame, if desired, to cushion the jar when the swinging frame is brought back into position against the stop 21 by the action of the weight W and cable 28.

A vertical pivoting bracket 30 is pivotally supported near the top between the pair of uprights 2|. is formed into a tubular housing 3| in which the end of a rod 32 is slidably mounted. A pin 33 extends diametrically through the tubular housing 3| and through a longitudinal slot 34 provided in the rod 32, and thus limits the extent of the telescoping or sliding movement of the rod 32 in the housing 3|. A coil spring 35 is located between the inner end of the rod 32 and an adjustable disk 36 located in the corresponding end This spring tends to keep the rod 32 in its maximum extended position. An adjusting screw 31, connected with the disk 36, and extending through a cap attached to the end of the housing 3| enables the tension of the spring 35 to be adjusted slightly when desired.

The top of this vertical pivoting bracket 30 A pair of small parallel vertical plates 38, attached to opposite sides of the end of the rod 32, provide a mounting for a stub shaft 39. The inner end of stub shaft 39 is pivotally supported on a bolt extending through the plates 38. A pin 4| extending through holes provided in the plates 38 and through a hole in the stub shaft 39 holds the stub shaft 39 in a desired predetermined position. A row of holes in the two plates 38, through which the pin may extend, enable the position of the stub shaft 39 to be adjusted, as apparent from Fig. l.

A rotatable head 42, preferably shaped as shown in Figs. 1 and 2, is mounted on the stub shaft 39, suitable means being providedto hold the head on the stub shaft while allowing the head to rotate freely. The outside surface of the head 42 may be covered with small spikes (not shown), or may be roughened or covered with any surfacing which will cause the head to engage the bark surface of the slats when the head 42 is brought into contact with the :slab in the position indicated in Figs. 1 and 2.' Thus the pivoting bracket 33, rod 32, and stub shaft 39 constitute in effect a composite adjustable arm, carrying an engaging element, for contacting and engaging the slab which is being sawed from the log.

A rack bar 43 'is pivotally connected to the bottom of the pivoting bracket 30. The rack bar is slidably supported for horizontal sliding motion and is engaged by a pinion 44 which is driven, through the intermediary of suitable gearing, by a reversible motor 45.

The operation of the device briefly is as follows:

The operator stands near the controls (not shown) of the reversible motor 45. Before starting the operation the bar 32, and with it the head 42, is raised slightly above the level of the top of the log L. 'The'pl'atform I! of the swinging frame will be in the starting position shown in Fig. 2, that is, will be resting against the stop 21, having been brought to that position by the pull of the cable 29 with the attached weight. The operator lowers the bar 32 until the head 42 contacts the slab which is being sawed. Since the slab i movin at fairly rapid speed there will momentarily be a tendency for the end of the bar to swing in the same direction in spite of the fact that the head is rotatably mounted. The

swing frame will permit such side swing to take place and thus takes up the shock which would otherwise be delivered to the arm at the first impact of the head with the slab. The lowering of the bar 32 is done, as previously explained, by the operation of the motor 45 and the moving of the rack bar 43 to the right as viewed in Fig. 1. The operator momentarily stops further operation of the motor and watches the slab. The engagement of the head 42 with the surface of the slab, due to the shape of the head and the engaging elements on the surface of the head, will help to hold up the forward portion of the slab while the saw is completing the cut. When the sawing of the slab i approximately completed the motor is again operated to lower the ba 32 to enable the head 42 to follow the slab as it drops downwardly. Continued operation of the motor in the same direction causes the head 42 not only to continue in contact with the slab, but, when the slab is in some such position as indicated by the dotted lines in Fig. 1, to push downwardly on the slab so as to bring it down quickly into the desired final position on the rolls l3 with the sawed fiat face on the bottom of the slab resting on the rolls. As soon as the slab is in the final desired position, the motor 45 is reversed by the operator. This lifts the head 42 from the slab and raises the rod 32 and head 42 in readiness for being brought down into contact with the slab to be cut from the next log.

We claim:

1. In a mechanical off-bearer assembly for facilitating the handling of a slab as it is being cut from a log, a frame located a spaced distance from the log and on the slab side of the log, said frame mounted for limited swing in a horizontal plane, an arm mounted on said frame and extending towards said log and slab from said frame, means for moving said arm up and down, a member rotatably mounted on the end of said arm and so positioned as to be contacted by and to bear against the slab when said arm is in starting position, said member rotated substantially in the direction of the log travel by contact with the slab, and slab-conveying means located below the slab and said member for receiving the slab when the severing of the slab from the log is completed, whereby said member when first contacted by the slab, by exerting an outer side thrust against the slab, will prevent the slab momentarily from tipping outwardly from the log, and whereby said member and said arm can be moved downwardly with the slab when the slab is severed from the log to facilitate the sliding of the slab into desired position on said slab-conveying means.

2. In a mechanical off-bearer assembly of the character described, a frame located a spaced distance from the log and on the slab side of the log, said frame mounted for limited swing in a horizontal plane, an arm mounted on said frame and extending towards said log and slab from said frame, means on said frame for moving said arm up and down in a vertical plane, the plane of said up and down movement of said arm being perpendicular to the axis of the log when said frame is in normal position, a member rotatably mounted on the end of said arm and so positioned as to be contacted by and to bear against the slab when said arm is in starting position, said member rotated substantially in the direction of the log travel by contact with the slab, said member having a surfacing for frictionally engaging the outer surface of the slab, and slab-positioning rolls located below the slab and said member for receiving the slab when the severing of the slab from the log is completed, whereby said member when first contacted by the slab, by exerting an outer side thrust against the slab, will prevent the slab momentarily from tipping outwardly from the log, and whereby said member and said arm can be moved downwardly with the slab when the slab is severed from the log to facilitate the sliding of the slab into desired position on said rolls.

3. A mechanical off-bearer assembly of the character described for facilitating the handling of a slab as it is being cut from a log, said assem-- bly including a frame located a spaced distance from the log and on the slab side of the log, said frame mounted for limited swing in a horizontal plane, a composite arm mounted on said frame and extending towards said log and slab from said frame, means on said frame for moving said arm up and down in a vertical plane, the plane of said up and down movement of said arm being perpendicular to the axis of the log when said frame is in normal starting position, means for bringing said frame to said normal starting position, a head rotatably and adjustably mounted on the end of said arm and so positioned as to be contacted by and to bear against the slab when said arm and said frame are in starting position, said head rotated substantially in the direction of the log travel by contact with the slab, said head having engaging elements on its surface for engaging the outer surface of the slab, and ofi-bearing rolls located below the slab and said head for receiving the slab when the severing of the slab from the log is completed, whereby said head when first contacted by the slab, by exerting an outer side thrust against the slab, will prevent the slab momentarily from tipping outwardly from the log, and whereby said head and said arm can be moved downwardly with the slab when the slab is severed from the log to facilitate the sliding of the slab into desired position on said rolls.

GEORGE W. CHARTERS.

BERNARD H. MICHELS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 550,825 Gray Dec. 3, 1895 707,806 Thomas Aug. 26, 1902 752,440 Davies Feb. 16, 1904 1,177,705 Johnson Apr. 4, 1916 1,180,918 Hamilton Apr. 25, 1916 1,252,894 Fitzgerald Jan. 8, 1918 1,531,367 Ahrens Mar. 31, 1925 2,468,036 Charters Apr. 26, 1949