US3732765A

US3732765A - Sweep table for wood-processing mill

Info

Publication number: US3732765A
Application number: US00201730A
Authority: US
Inventors: R Fritz
Original assignee: Albany International Corp
Current assignee: Albany International Corp
Priority date: 1971-11-24
Filing date: 1971-11-24
Publication date: 1973-05-15
Anticipated expiration: 1990-05-15
Also published as: CA961739A; AU475645B2; AU4549672A

Abstract

An outfeed conveyor table has two sets of sweep fingers positioned behind four ganged saws of a wood-processing mill. The saws are laterally adjustable to vary their spacing. Each set of sweep fingers can be aligned independently of the other set in a home position behind any one of the four saws and maintained in its selected home position by an independent setworks which coordinates the movement of the set of fingers with any movement of its corresponding saw. Each finger set can also be positioned at either side of the conveyor path and swept to the opposite side to sweep all cut material laterally in either direction from the table. From any of their home positions, one finger set is adapted to sweep in one direction across the table while the other set is adapted to sweep in the opposite direction. Either or both sets of fingers can also be maintained in retracted positions to permit some or all cut pieces to pass downstream from the end of the conveyor table.

Description

United States Patent Fritz et al.

3,732,765 May 15, 1973 5 SWEEP TABLE FOR W001). Primary Examiner-Donald R. Schran PROCESSING MILL Attorney-Stephen W. Blore, Kenneth S. Klarquist [75] Inventors: Rene Fritz; Rene E. Fritz, both of -andjoseph Sparkman Albany Oreg- 57 ABSTRACT [73] Assign: Albany International Industries An outfeed conveyor table has two sets of sweep fin- -a Albany, Oreggers positioned behind four ganged saws of a wood [22] Filed: 24 1971 processing mill. The saws are laterally adjustable to vary' their spacing. Each set of sweep fingers can be PP ,730 aligned independently of the other set in a home position behind any one of the four saws and maintained in its selected home position by an independent set- [52] US. Cl ..83/102 works which coordinates the movement of the set of [51] Int. Cl ..B27b 15/08, 1327b 31/08 58 Id is h 143/37 R 37 B 37 A fingers with any movement of its corresponding saw. 1 g g R 15 22 R Each finger set can also be positioned at either side of 14 H 7 157 7 the conveyor path and swept to the opposite side to 5 5 83/160 102 sweep all cut material laterally in either direction from the table. From any of their home positions, one finger [56] References C'ted set is adapted to sweep in one direction across the UNITED STATES PATENTS table while the other set is adapted to sweep in the opposite direction. Either or both sets of fingers can also 3,017,909 1/1962 Bowling et a]. ..143/157 D be maintained in retracted positions to permit some or 3,101,755 8/1963 stupfel 6t 81 D all cut pieces to pass downstream from the end of the 3,148,715 9/1964 Alter ..143/157 D conveyor table 18 Claims, 12 Drawing Figures 12a 30 L32. i, L l ----I:=T---== l 3: I2 b I2c ll if I l PATENTEU W1 5' RENE FRITZ RENE E. FRITZ INVENTORS.

FIG. 3

I) RENE FRITZ RENE E. FRITZ INVENTORS.

BUCKHORN, BLORE, KLARQUIST & SPARKMAN ATTORNEYS SWEEP TABLE FOR WOOD-PROCESSING MILL BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wood-processing mill and more particularly to a sweep-type outfeed conveyor table positioned downstream of a saw for conveying the multiple pieces cut by the saw selectively in various directions.

2. Description of the Prior Art In the past, outfeed tables downstream of agang of saws have utilized side-sweeping fingers or blades selectively to sweep some or all pieces cut by the saw from the side of the table.

In one prior device of this type, known as an edgerpicker, one or two long blades are aligned behind edger saws to sweep sideways and remove one or both edge trimmings from the downstream conveyor table as the edged piece is conveyed downstream from the table. However, these edger-picker remain aligned behind a predetermined edging saw and are designed, therefore, only for a single function, to remove edge trimmings.

In another prior outfeed conveyor table of the sweepblade or finger type, a set of sweep fingers is positioned at one side ofthe table or the other and sweeps across the full width of the table to push all cut pieces from one side of the table or the other. However, it is not capable of sweeping only some of the pieces from the side of the table. Therefore this table provides only three options.

In another prior type of sweep table, a single set of sweep fingers can be aligned behind a laterally movable saw and swept in one direction across the table therefrom to remove some pieces cut by the saw' sideways from the table while the remaining pieces move downstream from the table. Alternatively, these same sweep fingers can be positioned initially at one side of the table and then swept the full width of the table to remove all pieces sideways from the table. Alternatively, the same fingers canbe retracted below the level of the conveyor table, thereby permittingall pieces to be removed downstream from the table. However, the fingers of this table can be aligned behind only one saw, and cannot sweep .in both directions from its home position behind this saw. Therefore it provides a total of only three options.

Despite the several options provided by the prior sweep tables, none in the past has had the capability of selectively sweeping one or more pieces sideways in one direction from the table, while one or more other pieces are swept sideways in the opposite direction from the table, and while still other pieces pass downstream from the table. Also, no prior sweep table has combined the foregoing capability with the options of either sweeping all pieces in either direction sideways from the tables or conveying all pieces downstream from the table. Furthermore, no prior sweep table has had the capability with the foregoing options of selectively varying the number of pieces that can be conveyed in any one of the three mentioned directions.

In present multiple-saw wood-processing mills, the need for an outfeed table having the foregoing versatile capabilities has developed. As a large piece of lumber passes through a mill, which may include four or more ganged saws, reducing the large piece to five or more smaller pieces, it is often desirable to direct some of the pieces in one direction downstream of the saw, for example, to an edging or trimming station, while at the same time letting other, finished pieces pass downstream from the table, and while simultaneously directing still other pieces sideways in the opposite direction to be recirculated through the same gang saws for further cutting. Until now, no sweep table system has had the capability and versatility necessary to carry out all of the foregoing functions.

SUMMARY OF THE INVENTION In accordance with the present invention, a fingertype sweep table is capable, in its illustrated preferred form in conjunction with four ganged saws, of providing twenty-one conveying options on the five pieces produced by such saws. First, it can sweep all pieces sideways in either direction from the table, or permit all pieces to pass downstream from the table. Second, it can sweep, selectively, any number of pieces less than all from one side of the table while sweeping the remaining pieces from the opposite side of the table. Third, it can sweep any number less than all of the pieces from the opposite side of the table while sweeping ant of the remaining pieces from one side of the table. Fourth, it can simultaneously sweep a variable number of pieces from one side of the table while sweeping another variable number from the opposite side of the table and permitting still another variable number of pieces to pass downstream from the table.

In the preferred form of the invention, the foregoing is accomplished by providing two sets of sweep fingers, each set of which can be aligned selectively behind any one of the four saws, including any of the laterally movable saws. Furthermore, each set of fingers has a capability of maintaining its selected alignment behind any saw. Each set also, when desired, can be positioned at one edge of the table and swept to the opposite edge. The variations in sweep functions that can be accomplished by each set is accomplished by providing each set of fingers with its own independent setworks which can be operated independently of the setworks for the saws and other set of fingers. Furthermore, each finger of a set is provided with its own integral lumber carrier shoulder for accomplishing the partial sweep functions. Full sweep functions are accomplished by an independent full width skid bar selectively movable toa level above the downstream conveyors of the table when full width sweep is desired. I

A primary object of the invention is to provide a sweep table with a set of retractable sweep fingers selectively movable in either of laterally opposite directions from a home position behind a selected saw for providing a partial sweep in either lateral direction and also capable of sweeping the full width of the table for providing a full sweep in either direction.

A second primary object of the invention is to provide a sweep table having a set of sweep fingers selectively alignable in a home position behind any of two or more saws of a multiple saw mill, with means to maintain such selected alignment, and with means for sweeping laterally from any of its home positions.

A third primary object is to provide a sweep table with a set of sweep fingers selectively alignable in a home position behind any of two or more movable saws, with means to maintain any selected alignment, and with the set being capable of sweeping across the table from any of its home positions, and further being capable of sweeping in either direction the full width of the sweep table.

A fourth primary object is to provide a sweep table having two sets of sweep fingers operable independently of one another.

A fifth important object is to provide a sweep table having two sets of sweep fingers, each of which can be selectively aligned behind any one of two or more saws of a multiple saw mill, selectively maintained in such alignment, and selectively swept in opposite directions from any of their home positions, and with at least one set being capable of sweeping across the full width of the table.

A sixth important object is to provide a single outfeed conveyor table of the sweep finger type that can replace the edger-picker table and sweep tables commonly used in tandem in the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description which proceeds with reference to the accompanying drawings wherein:

FIG. 1 is a schematic plan view of an edger-resaw apparatus including an outfeed conveyor table in accordance with the invention;

FIG. 2 is a plan view of the outfeed table of FIG. 1 on an enlarged scale:

FIG. 3 is a longitudinal sectional view taken along the line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along the line 4 4 of FIG. 3-,

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 3;

FIG. 6 is a partial side view on an enlarged scale of one of the sweep fingers of FIG. 3 and the mechanism for operating the same;

FIG. 7 is a sectional view taken along the line 7-7 of FIG. 6;

FIG. 8 is a schematic diagram of a control system for operating the apparatus; and i FIGS. 9, 10, 11 and 12 are perspective views illustrating the operation of the apparatus.

DETAILED DESCRIPTION With reference to the drawings, FIG. 1 shows a wood-processing mill known as an edger-resaw apparatus and including an infeed section 10, a saw section 12, an outfeed section 14 and a control station (not shown). The saw section includes four

band saws

12a, 12b, 12c, 12d positioned so that their blades are laterally spaced apart across the path of wood pieces traveling from the infeed section through the saw section and onto the outfeed section. The saw section also includes a line bar 18 and two side press rolls 20, 21 used to press a log, cant or board against the line bar while feeding the same through the saws.

In the illustrated edger-resaw system, three of the

saws

12a, 12b, 12c are laterally movable by their

own setworks

24a, 24b, 240, respectively, to vary the lateral spacing between blades. The line bar 18 also has a setworks 26 for the same purpose. Alternatively, all four saws could be provided with setworks, with the line bar being fixed. Various other combinations of fixed and movable saws and line bar are possible, depending on the needs of the user. The saw section as thus described is conventional.

Infeed section 10 may also be of a well-known type such as, for example, the infeed section shown in copending application Ser. No. 885,389, filed Dec. 15, 1969, now US. Pat. No. 3,687,269. Such infeed section typically includes a series of driven conveyor rolls or chains, mechanism for positioning a log, cant or piece of lumber on the conveyor section and mechanism for turning the piece about its axis to a desired orientation. Pieces to be cut can be fed to infeed section v 10, either in the direction indicated by the arrow 28 from a head rig or in the opposite direction indicated by arrow 29 from a recirculation conveyor or so-called rrrerry-go-round leading from the outfeed section. Pieces are recirculated when it is desired to rerun a piece through the saw section to further reduce its size or remove an edge.

Referring now to outfeed section 14, in the edgerresaw apparatus shown, it is desired to convey pieces cut in the saw 12 in any one of three possible directions from the outfeed section. First, finish-cut pieces are conveyed downstream from the end of the outfeed section in the direction indicated by arrow 30. Second, pieces to be further broken down are conveyed off the left side of the outfeed section of FIG. 1 in the direction indicated by arrow 31 for recirculation to infeed section 10 for further cutting. Third, pieces to be edged are conveyed off the right side of outfeed section 14 in the direction of arrow 32 to a separate edger apparatus.

It will be appreciated that the so-called quad-saw I section 12 of the apparatus will deliver up to five cut pieces to outfeed section 14. In some instances it may be desired to convey all such pieces from the end of the outfeed section. In other instances it may be desired to rerun all pieces, and therefore sweep them all from the left side of the outfeed table. In still other instances, it may be desired toedge all pieces and therefore sweep them all from the right side of the outfeed table. In still other instances, some of the pieces may need to be rerun while others need to be edged and still others are finished and can be conveyed from the end of the outfeed table. With the outfeed sweep table about to be described, 21 options are provided for handling up to five pieces delivered to the outfeed table by the quad saws. Using the same sweep table with a twin saw section 12 producing up to three pieces of lumber, 1O optional ways of handling such pieces are provided by the illustrated sweep system.

Referring to FIGS. 2 through 5, the outfeed conveyor table or sweep table 14 includes

opposite frame members

34, 35 interconnected along their lengths by suitable cross frame members (not shown) and supported above ground level on legs 36. The table includes a series of live conveyor rolls 38 extending at intervals across the width of the conveyor table. These rolls are continuously driven through a sprocket 39 and chain 40 drive arrangement from a common source of power (not shown). The rolls 38 are driven in ,a direction for conveying pieces downstream from the saw section and from the downstream end of the conveyor table.

The outfeed table also includes two sets of sweep fingers including a first set indicated generally at 42, and a second set indicated generally at 44. The first set includes three

sweep fingers

42a, 42b, 420. The second set includes three

other sweep fingers

44a, 44b, 44c.

Each

fingers

42, 44, as shown in FIG. 6, includes a blade portion 46 having a forward edge 48 beveled to a point as shown in FIG. 7 so as to readily enter the small spacing between pieces as they arrive from the saw section, which spacing is approximately only the width of the saw kerf. The finger tapers from its relatively narrow outer tip to a widened base portion which has a curved slot 49 therethrough. This slot receives a chain connector 50 which connects the base of the sweep finger to endless chain 52 as shown best in FIG. 4 and 5. Chain 52 is trained about

sprockets

54, 55 at opposite sides of the conveyor table. The sprocket 54 is keyed to a longitudinal shaft 56. Sprocket 55, however, is rotatably mounted on a second longitudinal shaft 58. There is a corresponding sprocket 54 keyed to shaft 56 for each of the three

sweep fingers

42a, 42b, 42c. Similarly, there are three sprockets 55 rotatably mounted on shaft 58, one for each of the same three sweep fingers.

Near the downstream end of shaft 56 another sprocket 60 is keyed to the shaft. Similarly a sprocket 61 is rotatably mounted to shaft 58 near its downstream end. These two sprockets receive an endless chain 62. This chain is connected to a slide member 64 slidable along a cross shaft 66 below the lower run chain 62. Slide 64 is connected by a connector member 68 to the outer end of the piston rod 70 of a sweep cylinder 72 supported on a platform 74 extending from one side of the conveyor table.

Sweep finger 42c has a hub portion 76 mounted for sliding movement along a cross shaft 78 of square cross section which extends across the width of the conveyor table. Thus when the sweep cylinder 72 is retracted as shown in solid lines in FIG. 4, skid finger 42c and every

other sweep finger

42a and 42b of the same set, because of similar mountings, are positioned at the lefthand side of the sweep table. Upon extension of sweep cylinder 72, slide member 64 is moved to its dashedline position shown in FIG. 4 which in turn moves chain 62 thus through sprocket 60, shaft 56 and sprocket 54, chain 52 and sweep finger 42c on shaft 78, across the width of the conveyor table to the dashed-line positions of FIG. 4. Retraction of the sweep cylinder 72 again will, of course, sweep fingers 42 to the left in FIG. 4, to the opposite side of the table, whereby anything on the conveyor table off the left side of such table.

Each

sweep fingers

42a, 42b, 42c includes a lumber carrier shoulder 80 projecting from the left side of the finger as viewed in FIG. 4 at a level just above the conveyor rolls 38 when such fingers are in their upright positions. These shoulders raise lumber pieces from rolls 38 when their fingers swing from a retracted position below the rolls to an extended position above the rolls while in alignment with one of the saws. The shoulders thcn carry such raised pieces from the conveyor table as the fingers are swept to the left in FIG. 4 from their home positions. Thus sweep fingers 42, with their left projecting carrier shoulders, are designed for sweeping material from the left side of the table. Conversely, the sweep fingers 44 which, as evident from FIGS. 2 and 5, have their carrier shoulders 82 projecting toward the right side of the table, are design for sweeping material from the right side of the table.

It has been mentioned that

sweep fingers

42, 44 are capable of pivoting movement between a retracted position below the level of the conveyor rolls 38 and an extended operable position above the level of such rolls. This capability is illustrated in FIG. 6 with reference to a finger 42a but applicable to all

fingers

42 and 44. One end of the square shaft 78 on which the finger is slidably mounted is connected by a crank arm 84 to a longitudinally extending actuating rod 86 at a pivotal connection 87. The rod in turn is connnected at one end to a fluid-powered actuating cylinder 88. Extension of cylinder 88 imparts rotary motion to shaft 78 through crank arm 84 and thereby swings the finger 42a and all other fingers 42 connected to the same rod from their retracted positioned to their extended positions as shown respectively in dashed and solid lines in FIG. 6. Retraction of the cylinder 88, of course, reverses the movement of the fingers and returns them to their retracted positions. In their retracted positions all portions of each finger lie below the topmost level of the conveyor rolls, including the shoulder portions of such fingers. During swinging movement of the fingers, the sweep chains to which they are connected are unaffected because the chain connections ride in the arcuate slots 49.

A similar arrangement at the opposite side of the conveyor table utilizing an actuating rod (not shown) and actuating cylinder 92 (see FIG. 2) operates independently of the rod 86 and cylinder 88 to swing fingers 44 between retracted and extended positions.

The mechanism for sweeping the left-hand sweep fingers 42 has been described. The mechanism for sweeping the right sweep fingers 44 together across the sweep table is similar as will be apparent from FIG. 5. That is, finger 44c and each of the other fingers of the set is connected to a second set of endless chains 94 trained about a second set of

sprockets

96, 97 on the previously mentioned

shafts

56, 58. However, in contrast to the arrangement for fingers 42, the sprockets 97 for fingers 44 are keyed to shaft 58 while the sprockets 96 rotate freely on shaft 56, just the opposite of the arrangement for fingers 42. The downstream end of shaft 58 carries a sprocket 98 keyed to shaft 58. The downstream end of shaft 56 carries a second sprocket 99 freely rotatable thereon. An endless chain 100 trained about these sprockets is connected to a slide member 102 slidable on a cross shaft 104 extending below chain 100. Slide 102 in turn is connected to the outer end of a piston rod 105 of a second sweep cylinder 106 responsible for the right-hand sweep function of the sweep table.

Thus, referring to FIG. 5, with the sweep cylinder 106 fully retracted, the fingers 44 are in the left-hand dashed-line position shown. Upon extension of cylinder 106, fingers 44 sweep across the table toward the right, sweeping any material on the table from its right edge.

From FIGS. 4 and 5, it will be evident that the right and left edges of the sweep table are provided with means for removing pieces from the tables after they have been swept to the right or left edge by the sweep fingers. This means includes an inclined rollway extending at an inclination downwardly from the side edges of the table. Such rollway comprises a set of skate rolls 110 which convey the material under the influence of gravity and momentum induced by the sweep fingers themselves to an appropriate powered conveyor (not shown) or other appropriate means for conveying the pieces to a desired destination.

It has been mentioned that each set of sweep fingers has a partial sweep function and a full sweep function. That is, each set can sweep either the full width of the table to remove all pieces in one direction therefrom, or alternatively, the fingers of a set can be aligned behind one of the saws and swept from such home position to one edge of the table to remove only some of the pieces cut by the saws sideways from the table while permitting others to pass downstream from the table or in the opposite direction from the table. The carrier shoulders 80, 82 integral with the fingers of the two sets are designed to operate in carrying out only the partial sweep functions. They are not appropriate for performing a full sweep function since they are neither long enough to lift and carry all pieces coming from the saw section nor could the fingers conveniently be aligned in the proper position for accomplishing this full sweep function using the carrier shoulder. Therefore the sweep table is provided with a series of full width lift skids 112, as shown in FIGS. 2 and 3 for use in carrying out the full sweep function of either set of fingers. Normally the lift skids 112 are maintained in a retracted position below the level of the conveyor rolls 38 by the fluid-powered cylinders 114 to which they are connected. However, when a full sweep is desired in either lateral direction, the skid cylinders 1 14 are extended to raise skids l 12 above the level of the conveyor rolls and thereby lift all material from such rolls to stop its downstream movement. Thereafter, one or the other set of

fingers

42, 44, positioned at one side of the table or the other, pivot to their extended positions and sweep across the full width of the table, thereby sliding the lumber pieces along the skids 112 sideways from the table.

CONTROL SYSTEM Referring to FIG. 8, a control system is shown for positioning the two sets of sweep fingers as desired either behind one of the saws or at one side of the table and then moving them in desired directions to accomplish their partial or full sweep functions.

The overall control system actually includes three separate control systems which optionally operate independently of one another, or at least can be operated independently of one another. First there is a control system for the saws and line bar including their various setworks shown in FIG. 1. Then there is a second control system for the left-sweeping set of sweep fingers of FIG. 4 shown generally at 116 in FIG. 8, and a third control system for the right-sweeping set of sweep fingers of FIG. 5 shown generally at 118. The saw control comprises a setworks 24a, 23b24c for each

movable saw

12a, 12b, 12c and a fourth setworks 26 for the movable line bar 18. g l

The control systems of FIG. 8 are essentially means for controlling the stroke of each of the two

sweep cylinders

72 and 106. These are hydraulic control systems which control the metering of fluid into and out of the sweep cylinders for accomplishing one of the following objectives, including (1) positioning the set of sweep fingers in an initial home position, either at the righthand side of the table, the left-hand side of the table, or behind one of the four saws; (2) maintaining alignment of the set of fingers upon movement of one of the movable saws if the set is aligned behind such movable saw; (3) changing the home position of a set of fingers from behind one saw to a position behind any other saw or at one side of the table; (4) accomplishing a partial sweep function by sweeping the set from a selected home position behind any one of the four saws to one foregoing five objective with respect to each of the two sets of sweep fingers.

Control systems

116 and 118 are supplied with pressure fluid from a common hydraulic passage 120 leading from a variable output pump 122 and driven by an electric or other motor 123 through a suitable coupling 124. The two

control systems

116 and 118 are supplied with pressure fluid from common hydraulic passage 120 by parallel branch lines 125, 126, each provided with a variable flow control 127. Branch passages 125, 126 lead to

directional control valves

128, 129, each controlling, independently of the other, the sweep direction of their

respective sweep cylinders

72, 106 and corresponding sweep finger sets. Each such directional control valve is shown as a three-position spool valve spring-centered to a neutral position and either manually or automatically operated as desired.

Passages

130, 131 lead from each spool to the opposite ends of each

sweep cylinder

72, 106.

The circuit of each of the two systems shown also includes a line 132 bypassing each directional control valve and leading through a check valve 133 into one end of a setworks control box 134. Each setworks control box includes a system of valves, magnetic switch and servo valves operating an air cylinder. Such cylinder is operably connected as at 136 to its

corresponding sweep cylinder

72, 106 to move the piston rod of the appropriate sweep cylinder through a distance as dictated either by one of the saw setworks or by an operator at a remote control panel. In this way the fingers are either aligned with a desired saw or maintained in such alignment as the case may be.

Assuming first that the left-hand sweep fingers, controlled by sweep cylinder 72, are to be aligned behind one of the movable saws, the operator presses an appropriate button on the control panel to activate the air system of the setworks control box 134 in a manner so as to move the piston rod of cylinder 72 through a sufficient distance to align the connected sweep fingers with the desired saw. At the same time, the setworks control box 134 is operatively connected to the setworks of the selected saw in a manner so that operation of the saw setworks to change the positioning of the selected saw would also automatically adjust the position of the sweep cylinder 72 to maintain alignment of the fingers with the selected saw. The foregoing positioning of the sweep cylinder 72 through setworks control box 134 is permitted by the hydraulic control system of FIG. 8 when directional control valve 128 is in its neutral position. With the valve 128 in such neutral position, pump 122 pumps fluid from reservoir 138 through line and line into line 132, bypassing directional control valve 128 and directing fluid into both ends of cylinder 72, thereby tending to maintain the piston rod of said cylinder is a preselected position, with excess flow being returned to reservoir at 140. However, this hydraulic arrangement permits the setworks control 134 to change the position of the piston rod of cylinder 72 when desired since any movement of the piston rod under such condition will simply cause an exchange of fluid between the opposite ends of cylinder 72.

However, when it is desired to sweep the fingers controlled by sweep cylinder 72 to the right or left, valve spool 128 is moved to one of its two operating positions. For example, if spool 128 is moved to the right in FIG. 8, hydraulic fluid passes from line 125 through valve passage 128a and line 131 into the left end of sweep cylinder 72, moving the piston rod of such cylinder toward the right, thereby effectively overriding or bypassing any influence of the setworks control box 134. When this occurs, return fluid flow from the opposite side of cylinder 72 through line 130 and valve 12811 to reservoir at 142.

It is important to note that movement of the cylinder will occur so long as the directional control valve 128 is in one of its two operating positions. However, movement of the cylinder and thus its fingers will stop as soon as the valve is returned to its neutral position. The hydraulic circuitry disclosed holds the piston rod of such cylinder in a preselected position until changed under the influence of either setworks control box 134 or alternatively the sweep valve 128.

Although the operation of the left sweep positioner of FIG. 8 has been described, it should be understood that operation of the right-hand sweep positioner is similar, but entirely independent of the left sweep positioner.

The hydraulic control circuitry of FIG. 8 is completed with the usual pressure gauge 146, shut-off valve 147, high pressure relief valve 148, strainer 149 at reservoir 138, and float switch 150 at the reservoir.

Various other types of control systems could be used to accomplish the same results as described. For example, a system of setworks cylinders could be used to control the positioning of the sweep fingers rather than the single sweep cylinder shown. The finger setworks in such case would be similar in design to the saw setworks cylinders, which are well known in the art.

OPERATION FIG. 9 through 12 illustrate four of the 21 possible options in handling up to five pieces of lumber arriving at the outfeed section from the saw section.

Specifically, FIG. illustrates the full, right-hand sweep function wherein all five pieces P-1, P-2, P-3, P-4, P-5 of lumber cut at the saw section are swept by fingers 44 from the right-hand side of the sweep table. To perform this function, the operator at the operator station would press an appropriate button indicating full sweep right which would automatically program the control system to position fingers 44 initially at the left-hand side of the table in a retracted position with the other set of fingers 42 being retracted in any other previously selected position. When the five pieces P-l through P-5 arrive via the conveyor rolls 38 on the sweeptable, lift skids 112 are programmed to extend above the level of the conveyor rolls, thereby lifting all five pieces from the rolls. Thereafter sweep fingers 44 sweep from the left side of the table across to the right side of the table, removing all five pieces therefrom through extension of sweep cylinder 106. As this occurs, sweep fingers 46 remain in their retracted positions so as not to obstruct the sweeping action of fingers 44. After the full sweep function, fingers 44 retract and return to a previously selected home position behind one of the saws.

A similar sequence of operations occurs, but with sweep fingers 42 when it is desired to weep all five pieces from the left side of the sweep table.

F Ig. 9 illustrates the operation of the apparatus when it is desired to convey all pieces cut by the saws from the downstream end of the sweep table. When this is desired, the operator presses a button designated Full Straight or something similar, which programs the control system to maintain both sets of sweep fingers in their retracted positions as well as the skid rails 112 to permit the conveyor rolls 38 to convey all pieces from the downstream end of the table.

FIG. 11 shows the operation of the apparatus in sweeping one piece P-5 from the right side of the table, two pieces P-l, P-2 from the left side of the table, while permitting two other pieces P-3, P4, to pass straight from the downstream end of the table. To accomplish this the operator presses an appropriate button that programs the control system to align the set of fingers 42 behind the No. 3 saw 120 and the set of fingers 44 behind the No. 1 saw 12a. During this mode of operation, the lift skids are programmed tor remain retracted throughout the cycle.

Fingers

42 and 44 are initially retracted, but extend as soon as the pieces P-l through P-S arrive on the outfeed section to assume the positions shown in FIG. 11. Immediately thereafter, fingers 44 sweep to the right from their home position behind the No. 1 saw, carrying piece P-S on their shoulders 82. At the same time, fingers 42 sweep left to carry pieces P-1 and P-2 from the left side of the table on their shoulders 80. Pieces P-3 and P4, not having been lifted form the conveyor rolls 38 by the lift skids or the shoulder of the fingers, continue downstream under the influence of conveyor rolls 38 and are conveyed from the end of the table. Thereafter

fingers

42 and 44 retract and automatically return to their previous home positions.

It will also be apparent from FIG. 11 that fingers 42 could be aligned behind the No. 2 saw 12d to sweep three pieces from the left and permit only one piece to 7 pass downstream from the table. Alternatively, fingers 42 could be aligned behind the No. 4 saw 12b and sweep only one piece P-l to the left, permitting three pieces P-2, P-3, P-4 to proceed from the end of the table. Still other options are available to vary the number of pieces conveyed from the right side of the table by changing the home position of fingers 44 from behind the No. 1 saw to positions behind the No. 2, No. 3 or No. 4 saws.

FIG. 12 illustrates still other options available using the sweep table of the present invention. Under this series of options the control system can be programmed by the operator to align both sets of

fingers

42 and 44 behind the same saw. Thus fingers 42 sweep some pieces from the left side of the table while fingers 44 sweep the remaining pieces from the right side of the table, with no pieces passing downstream from the end of the table. In FIG. 12 both sets of

fingers

42 and 44 are aligned behind the NO. 2 saw 12d. When these fingers extend as shown, fingers 42 lift pieces P-1 P-2 and P-3 from conveyor rolls 38 onto their shoulders and then carry them to the left edge of the table. Simultaneously, fingers 44 lift pieces P-4, P-5 onto their shoulders and then carry them to the right side edge of the table.

In the illustrated embodiment, both finger set 42 and 44 can be aligned behind any of the other three saws so as to sweep from one to four pieces to the left side of the table while sweeping the remainder to the right side of the table.

In all there are 21 options provided by the illustrated fmger-and-control arrangement in conjunction with a guad saw mill as follows:

(1) Full sweep left; (2) full sweep right; (3) full straight out; (4) one left, four right; (5) two left, three right; (6) three left, two right; (7) four left, one right; (8 one left, four straight: (9) two left, three straight; 10) three left, two straight; (I l four left, one straight; 12) one right, four straight; (13) two right, three straight: (14) three right, two straight; (15) four right, one straight: (16) one left, one right, three straight; (17) two left, two right, one straight: (18) three left, one right, one straight; (19) one left, two right, two straight; (20) one left, three right, one straight; and (21) two left, one right, two straight.

With a sweep table having the same basic capabilities behind a twin or two-saw mill, a similar analysis will show that the three resulting pieces can be handled in ten different ways.

Essentially the same basic sweep tale system can be used advantageously behind a one-saw mill, a three-saw mill or a more-than-four saw mill.

Also, when the two sets of fingers are aligned behind the two outside saws of a two-, threeor four-or-more saw mill, the sweep table can function as an edgerpicker by sweeping the edge trimmings from opposite sides of the table while the remaining center cant or pieces pass downstream from the table. This feature eliminates the need for a conventional edger-picker table in addition to sweep table to fulfill this function.

A simplified version of the sweep table could comprise a single set of the illustrated sweep fingers, but equipped with an independent setworks or control system as described which enables the single set of fingers to be aligned in any one ofseveral home positions hehind two or more saws'of a multiple saw mill. Such sweep fingers can then be programmed to sweep either full right or full left in conjunction with a full width lift skid or can be programmed for a partial sweep right or left from any one of several home positions. For the partial sweep functions described, the table might also include partial width lift skids corresponding to each bf the partial sweep functions provided, as shown, for example, in prior co-pending application Ser. No. 885,389,-filed'Dec. 15, 1969.

Having illustrated what is presently a preferred embodiment of our present invention and several suggested modifications, it should be apparent to those means for selectively shifting said set together between inactive position below said conveyor path and active positions projecting above said conveyor path,

and means for selectively moving said set of finger means together 1) to a home position in alignment behind across said conveyor path, and (3) across the full width of said conveyor path in both directions, whereby lumber pieces cut by said saw can be selectively conveyed (a) all downstream from said table, (b) all in one lateral direction from said table, (c) all in the opposite lateral direction from said table, or part in either lateral direction and part downstream from said table.

2. Apparatus according to claim 1 wherein said saw is movable transversely of said conveyor path, and means for maintaining home position alignment of said set of finger means behind said movable saw.

3. Apparatus according to claim 1 wherein there is a second set of said finger means having a home position in alignment behind said saw and movable from its home position in at least one direction across said conveyor path and back to its home position.

4. Apparatus according to claim 2 wherein there is a second set of said finger means having a home position behind at least one said movable saw and movable from its home position in at lest one direction across said conveyor path and back to its home position, and

skilled in the art that the same permits of modification in arrangement and detail. We claim as our invention all such modifications as come within the true spirit and scope of the following claims.

We claim:

1. An outfeed table for a wood-processing mill having at least one saw defining a saw line, said outfeed table comprising:

conveyor means for conveying material downstream from said saw in a straight conveyor path generally parallel to said saw line,

a setof sweep finger means supported in longitudinal alignment with one another in the direction of said conveyor path,

means mounting said set of finger means for sweeping movement across said conveyor path,

means for maintaining home position alignment of said second set of finger means behind said movable saw.

5. Apparatus according to claim 1 including at least one saw movable transversely of said conveyor path, said finger set being movable across said path to maintain home position alignment of said set with said movable saw.

6. Apparatus according to claim 1 including at least two ganged laterally spaced saws defining parallel saw lines, said means for selectively moving said set of finger means behind each said saw.

7. Apparatus according to claim 6 wherein at leas one of said two saws is movable laterally of said conveyor path to vary the spacing between said saw lines, and means for selectively maintaining the alignment of said set of finger means behind said movable saw.

8. Apparatus according to claim 7 including a second set of said finger means movable independently of said first-mentioned set across said conveyor path from either one of two home positions, one in alignment with each said sawline, and means for maintaining said second set of finger means in home position alignment behind said movable saw.

9. Apparatus according to claim 1 wherein said wood-processing mill includes at least two laterally movable saws, said set of finger means being selectively alignable in a home position behind either one of said movable saws, and means operable to maintain the alignment of said set behind any one of said movable saws.

10. Apparatus according to claim 1 wherein said wood-processing mill includes at least two laterally movable saws, said outfeed table including two sets of said finger means, both said sets being independently selectively alignable in a home position behind all of said movable saws, both said sets including means for maintaining their home positions behind any selected one of said movable saws, one said set being movable from any of its home positions in at least one direction across said conveyor path and back to its selected home position, the other said set being movable from any of its home positions in at least the opposite direction across said conveyor path and back to its selected home position, and at least one or the other of said sets being movable across substantially the full width of said conveyor path for sweeping all material in one direction or the other from said table.

11. Apparatus according to claim 1 wherein said wood-process mill includes at least one fixed-position saw and at least one saw movable laterally to multiple positions, said outfeed table including at least two sets of said fingers means, each set being alignable selectively and independently of the other in a home position alternatively behind both said fixed saw and said movable saw, each set including means for maintaining alignment when selected behind said movable saw, one said set being movable from a selected home position behind either said saw across said conveyor path in at least one direction and back to said selected home position, the other said set being movable from a selected home position behind either said saw across said conveyor path in at least the opposite direction and back to its selected home position, at least one or the other of said sets being movable across the full width of said conveyor path in both directions to sweep all material in said path from said table in either lateral direction.

12. Apparatus according to claim 1 wherein said wood-processing mill includes at least three saws movable laterally to multiple positions, said outfeed table including at least two seats of said sweep finger means, each said set being alignable in a home position selectively and independently of the other said set alternatively behind all of said saws, each set including means for maintaining a selected home position alignment behind any said movable saw, one said set being movable from a selected home position behind any said saw across said conveyor path in at least one direction and back to its selected home position, the other said set being movable from a selected home position behind any said saw across said conveyor path in at least an opposite direction and back to its selected home position, at least one of said sets being selectively movable across the full width of said conveyor path in either lateral direction forsweeping all material in said path laterally from said table.

13. Apparatus according to claim 1 including lift skid means extending crosswise to said conveyor path and selectively movable between an inactive position below said conveyor path and an active position above said path for elevating material from said conveyor means.

14. Apparatus according to claim 1 wherein each finger means of said set includes a shoulder portion operable to elevate material form said conveyor means in the active position of said finger means and to carry material sideways from said table during sweeping movement of said finger means, said shoulder portion being below the level of said conveyor means in the inactive position of said set.

15. in a wood-process mill including a saw station with at least two gang saws spaced apart laterally to define parallel saw lines and means for moving at least one of saws laterally into multiple positions,

an outfeed table comprising:

conveyor means supported on said base means for moving material from said saw station downstream in a straight conveyor path generally parallel to said saw lines,

at least two sweep finger means extending longitudinally of said conveyor path,

means mounting each sweep finger means for movement across said conveyor path independently of the other sweep finger means,

means for shifting each said sweep finger means independently of the other between an inactive position below said conveyor path and an active position projecting above said conveyor path,

and means for moving at least one said finger means (l)into a home position alignment behind said movable saw, (2) from said home position in at least one direction across said conveyor path and back to said home position, and (3) so as to maintain said home position alignment upon movement of said movable saw,

said other finger means being movable from a predetermined home position in at least an opposite direction across said conveyor path and back to its home position.

16. Apparatus according to claim 15 wherein said other finger means has a home position alignable behind said movable saw and means for maintaining said alignment upon movement of said movable saw, and means for moving said other finger means from its home position across said conveyor path in a direction opposite the direction of movement of said one finger means from its home position, and means for moving at least one or the other said finger means across the full width of said conveyor path.

17. Apparatus according to claim 15 wherein at least one of said sweep finger means is movable into and maintainable in a home position behind both said saws and movable from either home position laterally in either direction across said conveyor path and further movable in both lateral directions across the full width of said conveyor path.

18. Apparatus according to claim 17 including lift skid means extending continuously across substantially the full width of said conveyor path and movable between an inactive position below said path to an active position above said path for lifting material above said conveyor means and enabling said one finger means to sweep material across the full width of said path from said table, each said finger means including lift shoulder means extending laterally therefrom at a level above said conveyor means in the active position of said finger means and at a level below said conveyor means in the inactive position thereof, the shoulder means on one said finger means extending in the opposite lateral direction to the shoulder means on said other finger means.

g 1 Of 4 CERTIFICATE OF CORRECTION Patent No. 3 732 a 765 Inventor(s) Dated May 15, 197-3 Rene Fritz et al.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line Column 1, 'line Column 2, line Column line Column line Column line Column line Column line Column line Column 5, line 20, after "edger-picker" insert blades 56, "tables" should read table Z3, "ant" should be any 30, the colon (z) should be a semicolon 21, between "saw" and "12" insert section 1, "fingers" should read finger 10, "FIG. should read FIGS.

25, after "run" insert of 40, after "62" insert and 45 "whereby anything on" should read thereby sweeping anytl-iing on Column 5,, line Column 6, line Column 6, line Column 7, line Column .7, line 47, "fingers" should read viiinger 11, "positioned" should read positions 56, "tables" should read table l5, "shoulder" should read shoulders 4.9, "-23b24c" should read 24b, 24c

2 of 4 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 8 Pa No, 5,732,765 Dated May 15, 1973 Inventor s Rene Fritz et a1 It is certified that error appears in the above-identified patent a and that said Letters Patent are hereby corrected as shown below:

Column 8, line 6, "objective" should read objectives Column 9 line 10 "flow" should read flows Column 9, line 11, after "valve" insert passage Column 9 line 41 "FIG should read FIGS.

Column 10 line 2 "weep" should read sweep 1 Column 10, line 4 "FIg. should read FIG Column 10, line 22, "tor" should read to Column 10 line 32 "form" should read from Column 10, lines 33 and 34 "shoulder" should read shoulders Column 10, line 59, "NO.2" should read No. 2

Column 10, line 60, "P-1 P-2" should read P-l, P-Z

Column 10, line 67, "set" should read sets Column 11, line 6, "guad" should read quad Column 11, line 23, "tale" should read table Column ll line 33, "to sweep" should read to the sweep Column 12, line 7, between "behind" and across" insert said Page 3 of 4 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 3,732,765 May 15, 1973 Patent No. Dated Rene Fritz et al. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

saw, (2) from said home position in both directions Column 12, line 27, "lest" should read least Column 12, line 39, between "means" and "behind" insert including means for aligning said set of finer means selectively Column 13, line 10, "process" should read processing Column 13, line 31, "seats" should read sets Column 13, line 54, "form" should read from Column 14, line 18, after "position" insert in

Claims

19, 20 and 21 is renumbered to read

Claims

1, 3, and 6 In the heading, under the Abstract, "18 Claims" should read 17 Claims Claim 15 should read as follows:

15. In a wood-processing mill including a saw station with at least two gang saws spaced apart laterally to define parallel saw lines and means for moving at least one of said saws laterally into multiple positions,

an outfeed table comprising:

conveyor means for movingmaterial from said saw station downstream in a straight conveyor path generally parallel to said saw lines,

at least two sweep finger means extending longitudinally of said conveyor path,

Pa 6 4 of 4 UNITED STATES PATENT OF FICE CERTIFICATE OF CORRECTION Q Patent No. ,765 Dated May 15, 1973 Inventor(s) Rene Fritz et al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

a and means for moving at least one said finger means (1) into a home position in alignment behind said movable saw, and (2) from said home position in at least one direction across said conveyor path and back to said home position, and

means for maintaining said home position alignment upon movement of said movable saw, said other finger means being movable from a predetermined home position in at least an opposite direction across said conveyor path and back to its home position.--

In the heading, under the Abstract, "18 Claims" will be changed to 17 Claims Signed and Sealed this ninth a O [SEAL] D y I f March 1976 Arrest:

RUTH' C. M AHSON C. MARSHALL DANN o Arresting Officer Commissioner nj'Patents and Trademarks

Claims

1. An outfeed table for a wood-processing mill having at least one saw defining a saw-line, said outfeed table comprising: conveyor means for conveying material downstream from said saw in a straight conveyor path generally parallel to said saw line, a set of sweep finger means supported in longitudinal alignment with one another in the direction of said conveyor path, means mounting said set of finger means for sweeping movement across said conveyor path, means for selectively shifting said set together between inactive position below said conveyor path and active positions projecting above said conveyor path, and means for selectively moving said set of finger means together (1) to a home position in alignment behind across said conveyor path, and (3) Across the full width of said conveyor path in both directions, whereby lumber pieces cut by said saw can be selectively conveyed (a) all downstream from said table, (b) all in one lateral direction from said table, (c) all in the opposite lateral direction from said table, or part in either lateral direction and part downstream from said table.

4. Apparatus according to claim 2 wherein there is a second set of said finger means having a home position behind at least one said movable saw and movable from its home position in at lest one direction across said conveyor path and back to its home position, and means for maintaining home position alignment of said second set of finger means behind said movable saw.

7. Apparatus according to claim 6 wherein at least one of said two saws is movable laterally of said conveyor path to vary the spacing between said saw lines, and means for selectively maintaining the alignment of said set of finger means behind said movable saw.

12. Apparatus according to claim 1 wherein said wood-processing mill includes at least three saws movable laterally to multiple positions, said outfeed table including at least two seats of said sweep finger means, each said set being alignable in a home position selectively and independently of the other said set alternatively behind all of said saws, each set including means for maintaining a selected home position alignment behind any said movable saw, one said set being movable from a selected home position behind any said saw across said conveyor path in at least one direction and back to its selected home position, the other said set being movable from a selected home position behind any said saw across said conveyor path in at least an opposite direction and back to its selected home position, at least one of said sets being selectively movable across the full width of said conveyor path in either lateral direction for sweeping all material in said path laterally from said table.

15. In a wood-process mill including a saw station with at least two gang saws spaced apart laterally to define parallel saw lines and means for moving at least one of saws laterally into multiple positions, an outfeed table comprising: conveyor means supported on said base means for moving material from said saw station downstream in a straight conveyor path generally parallel to said saw lines, at least two sweep finger means extending longitudinally of said conveyor path, means mounting each sweep finger means for movement across said conveyor path independently of the other sweep finger means, means for shifting each said sweep finger means independently of the other between an inactive position below said conveyor path and an active position projecting above said conveyor path, and means for moving at least one said finger means (1)into a home position alignment behind said movable saw, (2) from said home position in at least one direction across said conveyor path and back to said home position, and (3) so as to maintain said home position alignment upon movement of said movable saw, said other finger means being movable from a predetermined home position in at least an opposite direction across said conveyor path and back to its home position.