US3534786A - Sawmill carriage setworks mechanisms - Google Patents

Description

United States Patent m1 EhSZMJ/Wi Primary Examiner--Donald R. Schran Attorney Morsell and Morsell ABSTRACT: A sawmill carriage setworks mechanism having means for moving the headblock' knees forwardly and including a revoluble stop arm selectively engageable with a laterally adjustable stepped plate assembly to automatically stop the forward travel of said headblock knees at a predetermined position, thereby presenting the log for a cut of desired thickness, and said mechanism including means for rapidly moving said knees either forwardly or rearwardly when desired. Said setworks mechanism is entirely hydraulically actuated and controlled to minimize manufacturing costs, as well as to permit the use of the sawmill in remote areas where electric power is unavailable.

Patented Oct. 20, 1970 Sheet INVENTOR THOMAS P- MEIS Mv M ATTORNEYS Sheet 2 of 2 INVENTOR THOMAS F. MEIS MQLM ATTORNEYS fiAWlt/llllLlL CARRIAGE @lE'liWtZllilllh-i li/ilEtCllWlllSl /lS BACKGROUND OF THE ZNVENTEON 1. Field of the lnvention The present invention relates to lumber sawmills of the type used for sawing logs into boards or planks. More particularly the invention relates to a novel and improved carriage setworks mechanism for portable sawmills.

2. Description of the Prior Art in many conventional lumber sawmills the carriage setworks and drive mechanisms are electrically operated and controlled. Such electrically operated sawmills require multi ple solenoids, microswitches, limit switches, and other components which are not only relatively expensive, but which require frequent repair or replacement due to the rugged use to which a sawmill is necessarily subjected. Moreover, in many instances it is desirable to use portable sawmills in remote areas where electric power is not available. Examples of such conventional electrically operated sawmills are disclosed in US. Pat. No. 2,613,703 to Calvert, and No. 3,086,568 to liaitzell.

To remedy the drawbacks of conventional electrically operated sawmills attempts have been made in the past to design hydraulically operated sawmill setworlts mechanisms, but said prior units have been relatively complex and expensive, as well as being devoid of the fine adjustability and precision that is desirable in a sawmill. Typical of such prior hydraulic setworks mechanisms are those disclosed in the following US. Pats: Roberts, No. 2,548,067; Pelton, No. l,786,26l; and Langill, No. 1,832,908.

SUMMARY OF THE lllVENTlON The present invention provides a sctworks mechanism for sawmill carriages which is entirely hydraulically powered and controlled. The result is that with the present invention it is unnecessary to employ relatively expensive and fragile electri cal equipment; moreover, the sawmill can be utilized even in remote backwoods areas where electric power is unavailable.

A further important object of the present invention is to provide a novel hydraulically controlled sawmill setworks mechanism which permits the positioning of a log relative to the saw with great precision, to produce boards of accurate predetermined dimensions.

A further object of the present invention is to provide a sawmill setworlrs mechanism that can be operated and controlled remotely by the operator.

further object is to provide a totally hydraulic sawmill set- WOIliS mechanism which can be rapidly moved either forwardly or rearwardly by the operator, as he chooses, as well as including a plurality of independently adjustable forward movement stop selections that may be chosen at will by the operator.

It further object of the invention is to provide a hydraulically operated setworks mechanism which can be incorporated as standard equipment on new sawmills, or which mechanism can be readily installed on existing sawmills of conventional design.

Still further objects of the present invention are to provide a new and improved sawmill setworlcs mechanism that is simple and efficient in operation, which is rugged and durable in construction, which is relatively inexpensive to manufacture, and which is otherwise particularly well adapted for its intended purposes.

BRIEF DESCRIPTION OF THE DRA NlNG in the accompanying drawings, wherein the same reference numerals designate the same parts in all of the views:

Fl G. l. is a fragmentary side elevational view of a sawmill carriage of the type for which the improved setworks mechanism comprising the present invention is designed;

FIG. 2 is a rear elevational view of the setworks mechanism; and.

FlG. 3 is an end view of the setworlcs mechanism taken along the line Ii-3 of FIG. 2.

l lel""'.ng now more particularly to fli -S. l of the drawings. lllustr ed therein is a sawmill carriage l il oi the general type for which the novel setworks mesh dish: comprising the present invention is intended, said carriage being movably mounted on tracks lit. Carried on and extending transversely across said carriage iii? are a plurality of channelshaped headbloclcs l3 upon which the iog M to be sawed is rested, said log being positioned against two or more upright knee members l? which are movably carried in said headbloclts. The number of headblocks and knees mounted on the carriage can be varied, depending upon the size and style of the sawmill. Suitable power driven means are provided for shitting the carriage along the tracks it to move the log M into engagement with a high-speed rotary saw (not shown} positioned to traverse the length of said log to cut a board or plank therefrom After a board has been cut from the log the carriage ltl is returned to its initial position. The knee members are then shifted forwardly a predetermined distance within the headbloclrs to position the log for the next out To accomplish the adjustment of said movable knee members $7 a rack l8 projecting rearwardly from each of said knees is engaged by a pinion gear carried by a rotatable shaft t5, hereinafter referred to as the main set shaft. The means [or rotating said main set shaft and rack-engaging pinions to adjust the position of the knees i7 is commonly referred to as the sctworks mechanism. The purpose of the pre ent invention is to provide an improved sctworlts mocha n which is totally hydraulically operated, as will now be described.

With respect to the hydraulic circuitry. pumps and valve elements, etc. employed in the preferred form of the present invention, incidentally, it is to be understood that all of said components and circuitry are standard conventional hydraulic equipment such as is well known in the art. Under the circumstances, in order to simplify and clarity disc .xsure and to facilitate a clear understanding of the novel mechanical apparatus comprising the present inventio: dr riled descriptions of said conventional hydraulic co oi'icnts and circuitry will not be included herein.

Referring now to FIGS. 2 and the drawings, the setworlts mechanism featured in the present invention is suitably mounted adjacent and in association with the main set shaft i5 hercinabove described, said setworlcs mechanism including a supporting frame having a base El, upright end elements 22, 213, and a longitudinal top frame member 24. Associated with said main set shaft l5 are three major components: a sleeve 26 which surrounds a portion of said set shaft and is rotatable relative thereto; an enlarged set gear 1 which is mounted fast on said set shaft; and an enlarged sprocket Llil which is also mounted fast on said set shaft.

Attached to the rotatable, shaft-surrounding sleeve as is a hydraulic piston-attaching bar 29, the function of which will be hereinafter seen, and also operatively associated with said sleeve as are a so-called Bendix bracket arm 33. and a stop engaging bar 3?. (P16. 2). The set gear 27 is of a diameter and tooth sized to accommodate a small carried by an upper Bendix assembly 354 pivotally mounted on the bracket arm Both the Bendix assembly 3d and set gear 27 rotate about the main set shaft T5, with the result that said Bendix" assembly is adapted to partially traverse the periphery of said set gear during the operation or" the present invention, as will be described.

The lElendix"assembly is so designed as to provide rotation of the small gear 33 thereon in only one direction (coun terclocltwise in H0. 3 of the drawings). Theretore, when a double-acting hydraulic set cylinder 38 is actuated by the operator to extend the reciprocable piston All thereon in a downward direction the Bendix bracket arm 31, which is linked thereto by the bar 29, is caused to move in an upward direction. Because the small gear 33 on the Bendix' assembly will not rotate in said direction it causes the set gear 2'7 to rotate with said upwardly traveling bracket arm thus causing the main set shaft to also rotate therewith. The

rotation of said main set shaft turns the aforementioned pinion gear 19 to drive the rack 18 (FIG. 1) in a forward direction, thereby advancing the headblock knee 17.

With respect to said pinion l9 and rack 18, incidentally, it is to be understood that while a single pinion and rack assembly is shown in FIG. 1 of the drawing, in actual practice each headblock 17 on the sawmill carriage is provided with a similar rack and pinion assembly. All of the pinions 19 are mounted on the set shaft 15, of course, so that the multiple headblocks move conjointly to ensure a straight, even cut.

The travel distance of the racks 18 is governed by the amount of rotation of the pinion gears 19, which is determined by the amount of rotation of the set gear 27. As hereinabove described, the degree of rotation of the latter is controlled by the actuation of the hydraulic piston 40. Said set gear 27 will continue its turning movement until the hydraulic piston 40 either reaches the end of its stroke, or its stroke is in some manner restricted. One of the principal features of the present invention is the novel adjustable means provided for restricting the stroke of said piston, as will now be described.

As best appears in FIG. 2, slidably carried between upper and lower channel-shaped tracks 48, 49 is a plate 41 having a plurality of cutouts or steps 4347 formed in its forward edge, said plate being connected by a fitting 53 to a piston 52 and hydraulic cylinder 51. Said steps 43-47 extend diagonally from the approximate middle of the plate lower edge to the upper corner thereof, each step being spaced the same distance above the preceding step. A tapped, upwardlydirected bore is drilled in each of said steps to adjustably receive 21 depending bolt such as the bolt 43' shown in FIG. 2. While only one of said bolts is illustrated in the drawing for the sake of simplicity and clarity, it is to be understood that each of the steps 43-47 is designed to accommodate a similar depending bolt. said bolts 43are of a suitable size to sustain the force exerted by the hydraulic piston 40 without damage or wear when engaged by the stop abutment bar 32 as hereinafter described.

The extension of the reciprocable piston 52, hereinafter referred to as the stop cylinder piston, is controlled by the operator through a suitable metering valve, with the location of the laterally movable plate 41 associated therewith always indicated to the operator by means of a suitable linear gauge. The operator is thus-able to shift the plate 41 laterally to a position wherein the stop bar 32, which is revoluble with the sleeve 26, will abut the end of the bolt 43' depending from the particular selected stepped portion 43-47 of said plate, thereby preventing further extension of the piston 40 to halt the forward movement of the log-supporting headblocks l7. Said bolts are individually adjustable to permit the operator to control the thickness of the stock removed from the log with great precision. After each cut the hydraulic piston 40 is returned to its retracted position.

As the double-acting piston 40 returns to its retracted position it causes a corresponding downward movement of the connected "Bendix" bracket arm 31, which is permitted because the small gear 33 thereon is rotatable in a clockwise direction around the periphery of the set gear 27, as described. Pivotally mounted on a stationary bracket 35 (FIG. 3) therebelow is a lower Bendix assembly 37 including a small gear 36 which is normally spring-retained in meshing engagement with said set gear 27. Like the upper Bendix assembly hereinabove described, said lower Bendix assembly is rotatable in only one direction, thus eliminating the possibility of inadvertent reverse rotation of the set shaft when the piston 40 is being retracted. As the bracket arm 31 proceeds in a downward direction it engages a lever 42 (FIG. 3) attached to said lower Bendix assembly, causing the latter to pivot to a position where the gear 36 thereon is disengaged from the set gear 27 In order to shift the headblock knees to a rearward position, as when a new log is positioned thereon, it is necessary to rotate the set gear 27 in a reverse direction, of course. To accomplish such reversing action there is provided a bidirectional hydraulic motor 56 having a drive shaft 56(FIG. 2) with a small sprocket 55 thereon, there being a chain trained about said motor sprocket and about the aforementioned enlarged sprocket 28 carried on the set shaft 15. Said motor 56 can be driven in either direction, thus permitting the headblocks to be rapidly moved either forwardly or rearwardly. In the case of forward rotation there is no problem, as the lower Bendix assembly 37 is disengaged when the set cylinder piston 40 is retracted, as hereinabove described, while the upper Bendix" assembly 34 allows forward rotation of said set gear, as described. To permit reverse motion, however, the restriction of the upper Bendix" assembly, which permits only one-directional rotation, must be temporarily suspended.

To accomplish the latter function there is provided a singleacting Bendix release cylinder 57 which is spring-loaded to be self-returning. Said cylinder 57 is connected by means of a hydraulic fluid line to one of the ports in the bidirectional hydraulic motor 56 in a manner whereby when hydraulic fluid is directed therethrough said motor is caused to rotate in a reverse direction, thereby actuating the chain and sprocket 28 to cause reverse rotation of the main set shaft 15. Since the upper Bendix assembly prevents reverse rotation of the set gear 27, however, there can be no movement, thus causing the pressure upon the motor port connected to said release cylinder 57 to rise until said cylinder functions. Because the size of said release cylinder is relatively small in comparison with the motor 56, and because the power required to pivot the upper Bendix assembly 34 is minimal, said release cylinder 57 will function to pivot said Bcndix" assembly 34 prior to any rotation of the motor, thereby causing the set shaft 15 to rotate in a reverse direction. The result is that the operator can rapidly shift the headblocks either forwardly or rearwardly. as desired.

From the foregoing detailed description it will be seen that the present invention provides a novel sawmill setworks mechanism that is not only entirely hydraulically actuated. but which permits rapid bidirectional motim as well as multiple forward movement settings that can be selected at will by the operator. Moreover, absolutely accurate repeat motions on any given setting can be obtained, thus permitting the production of boards or planks of uniform thickness.

It is to be understood that while a preferred embodiment of the invention has been illustrated and described herein, numerous variations or modifications therein will undoubtedly occur to those skilled in the art. What is intended to be covered herein is not only the illustrated form of the invention, but also any and all variations or modifications thereof as may come within the spirit of said invention, and within the scope of the following claims.

Iclaim:

1. In a sawmill carriage assembly having a forwardly and rearwardly movable headblock knee with a rearwardly extending rack associated therewith, and having a rotatable set shaft with means thereon drivably engaged with said rack, a hydraulically powered drive and control mechanism, comprising: an operator-controlled hydraulic cylinder and piston; means operatively connecting said piston with said set shaft whereby extension of said piston causes rotation of said set shaft to drive said headblock knee in a forward direction; adjustable stop means including a laterally shiftable plate having a plurality of steps formed therein, including operator-controlled means for shifting and positioning said plate, a sleeve rotatably surrounding a portion of said set shaft, and including a stop element carried by and projecting from said rotatable sleeve engageable with a selected step on said stop plate to prevent further extension of said hydraulic piston to stop the forward movement of said headblock knee and hydraulic means for rotating said set shaft in the opposite direction to cause rearward movement of said headblock knee when desired.

2. The mechanism recited in claim 1 and wherein each of the steps in said stop plate is provided with an upwardly directed tapped bore to independently-adjustably receive a threaded depending abutment member.

3. The mechanism recited in claim 1 wherein said means for rotating said set shaft in the opposite direction to cause rearward movement of said headblock knee comprises: an enlarged sprocket mounted fast on said set shaft; a hydraulic motor having a drive sprocket; an endless chain trained about said motor sprocket and about said set shaft sprocket in a manner whereby rotation of said motor in one direction causes reverse rotation of said set shaft and rearward movement of the headblock knee; and operator-controlled means for actuating said hydraulic motor.

4. The mechanism recited in claim 3 wherein said hydraulic motor is bidirectional and is adaptable to rapidly drive said headblock knee in either a rearwardly or forwardly direction.

5. The mechanism recited in claim 1 wherein the means operatively connecting said piston with said set shaft comprises: a set gear mounted fast on said set shaft; a sleeve rotatably surrounding a portion of said set shaft; a bracket arm on and projecting from said sleeve; a small gear on said bracket arm normally positioned to mesh with said set gear and to partially traverse the periphery thereof, said small gear being rotatable in one direction only; and means connecting said piston to said bracket arm in a manner whereby downward extension of said piston causes upward movement of said bracket arm, thus causing said small gear thereon to engage and turn said set gear and shaft.

6. In a sawmill carriage assembly including a forwardly and rearwardly moveable headblock knee with a rearwardly extending rack, and including a rotatable main set shaft with a pinion thereon drivably engaged with said rack, a hydraulically powered drive and control mechanism, comprising: a set gear mounted fast on said set shaft; an enlarged sprocket mounted fast on said set shaft; a sleeve rotatably surrounding a portion of said set shaft; a bracket arm on and projecting from said sleeve; a small gear on said bracket arm normally positioned to mesh with said set gear and to partially traverse the periphery thereof, said gear being rotatable in one direction only; a double-acting hydraulic ram connected to said bracket arm whereby downward extension of said piston in response to actuation by a remote operator causes upward swinging movement of said bracket arm to rotate said set gear and main set shaft, thereby rotating said pinion and causing corresponding forward movement of the rack and headblock knee; a laterally adjustable stop plate having a plurality of steps formed therein; independently adjustable stop abutment members depending from each of said plate steps; an operator-controlled hydraulic piston attached to said plate and adapted to shift the same laterally; a stop bar carried by and projecting from said rotatable sleeve engageable with a selected stop abutment member on said laterally adjustable plate to prevent further rotation of said set gear and pinion, thus halting the forward movement of said headblock knee at a desired location to present a log thereon for a cut of predetermined thickness; means for retracting said piston; a bidirectional hydraulic motor having a drive sprocket; an endless chain trained about said motor sprocket and about said set shaft sprocket whereby rotation of said motor in one direction causes rapid rotation of the set shaft and forward movement of said headblock; and an operator-controlled hydraulic release means associated with said bracket gear and adapted to pivot the same out of engagement with said set gear to permit reverse rotation of said set gear and rapid rearward movement of the heatlbiock when said bidirectional motor is driven in the opposite directionv

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