Abstract: When arranging the geometry of knuckle booms with efficient hydraulic circuits it is sometimes necessary to place the cylinder that provides the reaching force above the boom so that its base area rather than its rod end area provides the boom point motion and force in the pulling direction. It is also sometimes necessary to provide equal areas for both pushing and pulling by further modifying the reach cylinder installation. In the invention, the knuckle boom apparatus has a machine base, a hoist boom and a stick boom. The stick boom has an intermediate pivot pinned to pivot on the distal end of the hoist boom, and a proximal end having a suitable cylinder push point. At least one hydraulic hoist cylinder is mounted between the machine base and the hoist boom, and at least one hydraulic stick cylinder is mounted between the hoist boom and the stick boom.

Abstract: An apparatus and method for harvesting trees and reducing their stumps is disclosed. The apparatus includes a rotating member including an upper disc saw blade and a lower stump grinding drum blade. The disc saw blade severs the tree from its stump, and thereafter the drum blade reduces the height of the stump down to at or near ground level.

Abstract: A disc saw felling head has a replaceable lower blade housing and an optional replaceable wear liner in the housing.

Abstract: A concrete engraver apparatus including a carrier for use with a hand-held engraver. The hand-held engraver is detachably mounted to the carrier. The carrier has wheels and a handle attached to an enclosure. The enclosure includes a vacuum mount for attaching a vacuum tube to evacuate loosened particles from the enclosure during operation of the hand-held engraver.

Abstract: The knuckle boom includes a hoist boom having a proximal end pivoted to a machine base, and a stick boom having a proximal end pivoted to a distal end of the hoist boom. At least one hydraulic hoist cylinder is mounted between the machine base and the hoist boom, and at least one hydraulic stick cylinder is mounted between the hoist boom and the stick boom. A hydraulic circuit supplies hydraulic oil to the cylinders, and provides an oil flow path between working ends of the cylinders so as to transfer a slug of pressurized hydraulic oil between the working ends. In one embodiment, reaching movement is controlled by a pump connected to control transferring of the slug between the hoist and stick cylinders. The pump determines which cylinder receives which portion of the slug of oil, and thereby controls the angle between the booms, thereby producing reach.

Abstract: Disclosed herein is an apparatus preferably coupled to a boom on a truck which can simultaneously trim and chemically treat trees or other vegetation with a herbicide. The apparatus, in addition to have a standard saw blade assembly with limb clamping jaws, includes a sprayer assembly. The sprayer assembly includes nozzles which administer herbicides or other chemical treatments adjacent to the saw blades, allowing herbicide to be precisely administered to the tree limbs as they are cut.

Abstract: An implement for clearing brush and trees which includes a self-propelled vehicle and at least one boom mounted upon the vehicle. The boom is constructed for articulated motion of a distal end thereof. A cutting disk is operatively mounted for rotation to the distal end of said boom to cut brush and trees when rotated. A secondary power source is supported on the self-propelled vehicle and used to primarily power the cutting disk. The implement is configured to allow field replacement of a cutting wheel support cartridge.

Abstract: A hydraulic circuit for a tree-cutting machine having a feed mechanism powered by hydraulic fluid at the output of a hydraulic motor. The hydraulic motor may comprise a variable-displacement motor. The hydraulic circuit may comprise elements which provide an anti-stall mode, wherein the feed mechanism is operated to withdraw the cutting element upon pressure at an input port of the hydraulic motor exceeding a threshold.

Abstract: The invention comprises a remote controlled power chain saw which can be remotely operated and remotely positioned to different heights and at different angles. The chain saw has a front and rear assembly with an endless chain with cutting teeth thereon which is pivotally mounted on a main frame of the front assembly and powered by a hydraulic cylinder to pivot downward about an axis out of the bottom of the assembly for using the chain to cut with power means to power the endless chain. The front assembly is pivotally mounted to the rear assembly about an axis perpendicular to the first mentioned axis and is power operated to pivot thereby pivot the chain to two different angles.

Abstract: A log delimbing processor includes two pairs of grapples for holding workpieces for translation along their length so as to engage delimbing knives. The workpieces are urged by a pair of driven wheels on opposite sides of the workpieces, by a driven upper roller mounted to a backbone of the processor, and by a driven lower roller mounted on the end of an articulated arm which is actuated to tuck up under the workpieces held in the grapples so that the workpieces are engaged and driven from all sides. A swing out saw on one end of the processor provides for delimbing large forked branches.

Abstract: Tree harvester (10) is mounted on tractor (12) to enable continuously cutting and chipping of trees. The harvester (10) includes a rotary saw (14) for cutting a tree near ground level, transport means (16) adjacent the rotary saw (14) for gripping a tree cut by the rotary saw (14) and transporting the tree to and dropping the cut tree in a chipper (18) located at an end of the transport means (16) distant the rotary saw (14). The transport means (16) includes first and second opposed conveyors (46, 48) each provided with laterally extending fingers (50) so that a cut tree can be gripped by the fingers (50) of the opposed conveyors (46, 48) and subsequently transported therebetween to the chipper (18).

Abstract: An implement for clearing brush and trees which includes a self-propelled vehicle and at least one boom mounted upon the vehicle. The boom is constructed for articulated motion of a distal end thereof. A cutting disk is operatively mounted for rotation to the distal end of said boom to cut brush and trees when rotated. A secondary power source is supported on the self-propelled vehicle and used to primarily power the cutting disk. The implement is configured to allow field replacement of a cutting wheel support cartridge.

Abstract: A tree cutting attachment for a skid loader or other types of self-propelled work vehicles to be used at construction and landscaping sites. The device is used to cut down brush and trees of up to about 12 inches in diameter. The tree cutting attachment is made up of a motor driven rotor assembly which is journaled within a frame of the attachment. The rotor assembly comprises a cage-like mounting system having pockets in which tempered steel blades, approximately ten inches in width are bolted in a side-by-side relation. Two rows of blades are mounted 180 degrees apart proximate the periphery of a rotor comprised of a series of parallel, generally circular plates that are welded to longitudinally extending rods. The knife blade elements are bolted to the blade holders with the non-sharpened end of the blade elements abutting a flat steel bar that forms part of the cage.

Abstract: The invention relates to a forest machine camprising a base (1) and a cabin (7), power source (8), loader (9) as well as a loading space (23) arranged thereto. The loading space is preferably arranged to form at the front end of the base a part connected with an articulated joint. In order to diversify the use of the forest machine, the cabin (7), loader (9) and power source (8) of the machine are arranged to be movable in relation to the base (1). Thus, depending on the location of the cabin, loader and the power source, the loading space in the machine is at least partly covered or released completely. A forest machine is thus provided that according to need is able to select between the most appropriate location of the centre of gravity and the use of the loading space (23).

Abstract: Methods for the harvesting of timber using a cutting sawhead having cutting elements of polycrystalline diamond (PCD) are provided. A sawhead having cutting elements of PCD extends the useful life of the blades, increases productivity and decreases downtown in timber harvesting methods. A method for harvesting timber in rocky and sandy soils using a sawhead with PCD tipped cutters is described. A cutting sawhead having cutting elements of PCD provide increased useful life compared to conventional steel and tungsten carbide cutting elements.

Abstract: A butt plate for a felling head includes a ramped portion in an accumulation pocket. The ramped portion is sloped downward generally toward a line extending in the direction of forward travel of the head. The butt plate allows for high accumulation of trees while retaining stable bunches.

Abstract: An apparatus and method for harvesting trees and reducing their stumps is disclosed. The apparatus includes a rotating member including an upper disc saw blade and a lower stump grinding drum blade. The disc saw blade severs the tree from its stump, and thereafter the drum blade reduces the height of the stump down to at or near ground level.

Abstract: A saw tooth of generally parallelopiped shape having top and bottom surfaces, side surfaces and front and back surfaces. Each front and back surface has cutting edges at its top and bottom sides. The cutting edges on each surface are parallel to each other and are also parallel to the cutting edges on the other surface.

Abstract: A feller buncher includes an elongate support having an axis, a first side, a second side, a first end and a second end. A first tree receiving cavity is positioned along the first side of the support. A second tree receiving cavity is positioned along the second side of the support. A circular saw is positioned at the second end of the support. The plane of the saw is transverse to the axis of the vertical support. Movable grapple arms are positioned on each of the first side and the second side of the support above the circular saw. The grapple arms are adapted to hold trees while they are being felled and then maintain bunches of felled trees in each of the first tree receiving cavity and the second tree receiving cavity.

Abstract: A cutter head assembly comprising a first longitudinal member; a second hollow longitudinal member provided with at least one aperture, being coaxial with the first longitudinal member and radially spaced apart therefrom; cup-shaped elements fixedly mounted to a corresponding aperture and to the first longitudinal member; blade holders to removably secure a rotatable blade to the cutter head. These blade holders are designed so as to improve mulching action and resistance to impacts of the cutter head, for use in land clearing and in any operation involving mechanical vegetation cutting.

Abstract: The invention relates to an apparatus and method for cutting submerged trees at an underwater logging site and for retrieving the cut trees. Once cut, each tree is retrieved to the water surface by an inflatable bag deployed from and inflated by the apparatus. The apparatus includes a control unit positioned on a surface vessel, such as a barge or large boat, and an underwater vessel connected together by an umbilical. Preferably the underwater vessel is a remotely controllable submersible including a grapple for releasably holding each tree to be cut, a saw, a gas supply connectable to a gas source located on the surface vessel, and an air bag deployment and inflation assembly for inflating the air bag and securely attaching it to the tree. The underwater vessel is initially loaded with a plurality of air bags which are stored in a magazine located in the interior of the vessel.

Abstract: The wood gathering and compaction vehicle comprises a vehicle frame movable over ground, a storage bin removably installed on the vehicle frame, with the storage bin having an inlet opening and an outlet opening. The vehicle further comprises a releasable bin attachment device for releasably attaching the storage bin to the vehicle frame, and a compactor fixedly installed on the vehicle frame, the compactor having an inner chamber, an opened inlet port for allowing wood to be inserted into the compactor inner chamber, an outlet port communicating with the storage bin inlet opening when the storage bin is installed on the vehicle frame, and a compaction device for allowing wood located in the compactor inner chamber to be forcibly moved from the compactor inner chamber into the storage bin through the compactor outlet port and the storage bin inlet opening.

Abstract: A hydraulic valve is used to judiciously shunt oil from lowering ends of the hoist and stick cylinders that have been plumbed to achieve near horizontal movement. This allows the use of cylinders that have unequal rod/bore ratios or to compensate for certain transient effects that may require the exchange of oil to the reservoir. The action of the hydraulic valve acts without obtrusive operator intervention and is essentially automatic. This allows for greater flexibility in the design of the boom system, allows the boom system to perform various tasks, while not requiring obtrusive intervention from the operator.

Abstract: A tree harvesting apparatus is provided. The harvesting apparatus comprises a frame member, a cutting device mounted to the frame member, and at least one cutting member attached to the cutting device. A tree accumulation member is also provided and overlays at least a portion of the cutting device. Also provided is a tree securing device for securing at least one tree on the tree accumulation member, and an adjustment device for automatically adjusting the position of the tree securing device relative to the frame member.

Abstract: The wood gathering and compaction vehicle comprises a vehicle frame movable over ground, a storage bin removably installed on the vehicle frame, with the storage bin having an inlet opening and an outlet opening. The vehicle further comprises a releasable bin attachment device for releasably attaching the storage bin to the vehicle frame, and a compactor fixedly installed on the vehicle frame, the compactor having an inner chamber, an opened inlet port for allowing wood to be inserted into the compactor inner chamber, an outlet port communicating with the storage bin inlet opening when the storage bin is installed on the vehicle frame, and a compaction device for allowing wood located in the compactor inner chamber to be forcibly moved from the compactor inner chamber into the storage bin through the compactor outlet port and the storage bin inlet opening.

Abstract: A mobile silvicultural apparatus for use in a land of trees comprising mature trees and immature trees. The apparatus includes a steerable wheeled support frame, an articulated boom, a motor system, and a control system. The steerable wheeled support frame has a horizontally extending ground-clearing section, and first and second opposite vertical side sections. The ground-clearing and side sections define a tunnel-shaped passage through which the immature trees are allowed to pass as the support frame travels thereover. The articulated boom is mounted to the support frame for selectively manipulating the mature trees. The motor system is used for imparting motion to the support frame and the control system is used for controlling the steerable support frame, the motor system, and the articulated boom.

Abstract: The subject of the invention is a grapple harvester which is equipped with a felling and cutting device (14), a feeder (12) and delimbing devices (9, 10, 11, 13). The grapple harvester according to the invention is equipped with a bulk handling device (4) which is arranged to grip together several trees, which are usually gathered one by one and, preferably, whilst in the vertical position, for cutting by the grapple harvester.

Abstract: A tree felling saw head has two pairs of links and two hydraulic actuators to provide high rotation of the head relative to a mounting adapter in a lateral plane which is perpendicular to a cutting plane.

Abstract: A hydraulic circuit for a tree-cutting machine having a feed mechanism powered by hydraulic fluid at the output of a hydraulic motor. The hydraulic motor may comprise a variable-displacement motor. The hydraulic circuit may comprise elements which provide an anti-stall mode, wherein the feed mechanism is operated to withdraw the cutting element upon pressure at an input port of the hydraulic motor exceeding a threshold.

Abstract: The two boom members and hydraulic cylinders of a knuckle boom tree harvesting machine are so arranged and proportioned that with a single control movement during reaching and retracting actions the working tool head is made to travel in an approximately horizontal path. The cylinders and control valve are so connected that during horizontal reaching action load-supporting pressurized oil from a collapsing cylinder is not required to be dumped to the reservoir in the conventional heat generating manner, but is rather shunted directly to an extending cylinder where it continues to do useful load support work. Energy waste to hydraulic oil heat and fuel consumption is significantly reduced. Although these advances have been particularly developed for disc saw felling and stroke delimbing of trees they can also be applied to other knuckle boom applications where horizontal reaching is a major function.

Abstract: A hydraulic valve is used to judiciously shunt oil from lowering ends of the hoist and stick cylinders that have been plumbed to achieve near horizontal movement. This allows the use of cylinders that have unequal rod/bore ratios or to compensate for certain transient effects that may require the exchange of oil to the reservoir. The action of the hydraulic valve acts without obtrusive operator intervention and is essentially automatic. This allows for greater flexibility in the design of the boom system, allows the boom system to perform various tasks, while not requiring obtrusive intervention from the operator.

Abstract: A method of harvesting standing trees in a jungle comprising bringing a crawler crane, preferably a hydraulic crawler crane, with a boom (14) to a block of jungle, securing the tree to be harvested to a sling in the boom, cutting the base of the tree, removing the cut tree using the boom, laying the cut tree on the ground, and cutting the crown of the cut tree. In another aspect the crown of the tree is cut first and removed by means of a sling on the boom of the crane. The crane is used to remove the crownless tree, or the crownless tree is cut at the base and allowed to fall. Main roads, spur roads, and snig tracks are constructed in the logging area.

Abstract: An implement for clearing brush and trees which includes a self-propelled vehicle and at least one boom mounted upon the vehicle. The boom is constructed for articulated motion of a distal end thereof. A cutting disk is operatively mounted for rotation to the distal end of said boom to cut brush and trees when rotated. A secondary power source is supported on the self-propelled vehicle and used to primarily power the cutting disk. The implement is configured to allow field replacement of a cutting wheel support cartridge.

Abstract: A rotary tree cutter attachment for a tractor includes a cutting assembly having a circular blade with a serrated outer edge, and a motor for rotatably driving the blade. A frame assembly for the tree cutter includes a first portion attached to the tractor frame, and a second portion extending perpendicular to the first portion and providing an offset mounting location outside a wheel path of the tractor. A pivot arm is pivotally connected to the offset mounting location for rotation about an axis transverse to the tractor's direction of travel. The pivot arm supports the cutting assembly and is movable about the transverse axis between a lowered position in which the cutting edge of the circular blade is generally horizontal and at ground level for cutting, and a raised position in which the cutting edge of the circular blade is elevated above ground level for traveling.

Abstract: A rotary tree cutter attachment for a tractor includes a cutting assembly having a circular blade with a serrated outer edge, and a motor for rotatably driving the blade. A frame assembly for the tree cutter includes a first portion attached to the tractor frame, and a second portion extending perpendicular to the first portion and providing an offset mounting location outside a wheel path of the tractor. A pivot arm is pivotally connected to the offset mounting location for rotation about an axis transverse to the tractor's direction of travel. The pivot arm supports the cutting assembly and is movable about the transverse axis between a lowered position in which the cutting edge of the circular blade is generally horizontal and at ground level for cutting, and a raised position in which the cutting edge of the circular blade is elevated above ground level for traveling.

Abstract: A tree felling saw head has two pairs of links and two hydraulic actuators to provide high rotation of the head relative to a mounting adapter in a lateral plane which is perpendicular to a cutting plane.

Abstract: A tree harvesting apparatus is provided. The harvesting apparatus comprises a frame member, a cutting device mounted to the frame member, and at least one cutting member attached to the cutting device. A base member partially overlays the cutting device. A tree accumulation member is positioned adjacent the base member and is co-planar therewith and extends over at least a portion of the cutting member.

Abstract: A guide bar having fluid conveying channels at the opposed sides. The channel on one side provided by the manufacturer with holes or orifices for dispensing treatment fluid from the channels onto a stump being sawn. The other side provided with markings to guide the operator in making holes or orifices at the time the bar is to be inverted. The markings may be dimples to provide centering of a piercing tool. They may also be provided at the sides of the channel and different marking sets will provide for different sizes of trees being cut.

Abstract: A tree pusher for safely felling trees. The tree pusher controls and determines the direction in which the tree falls, using a base, a frame, a detachable head which engages the tree trunk, and an extendable screw-type trailer jack that is repairable/replaceable during operation and capable of bearing the weight of a large tree, for urging the frame and the head against the trunk of the tree. For use on uneven ground, the tree pusher is provided with a base extension. A chain is used to connect the base of the tree pusher to the trunk of the tree, to prevent movement of the base when the jack is activated. The tree pusher can be readily moved to the job site, and can be used on any type of terrain, including hard surfaces, and for any type of tree, including trees with rotten wood.

Abstract: A method of harvesting standing trees in a jungle comprising bringing a crawler crane, preferably a hydraulic crawler crane, with a boom (14) to a block of jungle, securing the tree to be harvested to a sling in the boom, cutting the base of the tree, removing the cut tree using the boom, laying the cut tree on the ground, and cutting the crown of the cut tree. In another aspect the crown of the tree is cut first and removed by means of a sling on the boom of the crane. The crane is used to remove the crownless tree, or the crownless tree is cut at the base and allowed to fall. Main roads, spur roads, and snig tracks are constructed in the logging area.

Abstract: A land clearing tractor and process are provided for selectively clearing a land of brush and trees. The tractor has a traction unit for moving the tractor along a direction of travel. A supporting frame is connected to the traction unit. The frame has first and second sides, and a raised section between the first and second sides. A first shredder head is operatively connected to the first side of the frame and oriented parallel to the direction of travel. The first shredder head is movable between elevated and lowered positions for clearing brush and trees in a first band. A second shredder head is operatively connected to the second side of the frame. The second shredder head is parallel to the first shredder head and is spaced apart therefrom. The second shredder head is movable between elevated and lowered positions for clearing brush and trees in a second band spaced apart from the first band. Thereby, the tractor leaves between the first and second bands a residual band of brush and trees.

Abstract: A tree felling and shaping apparatus is provided with a fully powered and controllable link system which links a tree processor head to a boom that is in turn mounted to a vehicle. The link system includes two powered pivoting joints and a rotary coupling of up to 360° disposed therebetween. Such a combination provides a great convenience for the manipulation of the tree felling and shaping apparatus, not only permitting a maximum angular adjustment of the tree processor head for all directional orientations whether the head is in an upright position for felling trees or the head is in a recumbent position for processing trees, but also performing a universal joint function to freely suspend the tree processor head from the boom without using a conventional uncontrollable universal joint. The present invention improves maneuverability of the tree felling and shaping machines and thereby increases work efficiency.

Abstract: The two boom members and hydraulic cylinders of a knuckle boom tree harvesting machine are so arranged and proportioned that with a single control movement during reaching and retracting actions the working tool head is made to travel in an approximately horizontal path. The cylinders and control valve are so connected that during horizontal reaching action load-supporting pressurized oil from a collapsing cylinder is not required to be dumped to the reservoir in the conventional heat generating manner, but is rather shunted directly to an extending cylinder where it continues to do useful load support work. Energy waste to hydraulic oil heat and fuel consumption is significantly reduced. Although these advances have been particularly developed for disc saw felling and stroke delimbing of trees they can also be applied to other knuckle boom applications where horizontal reaching is a major function.

Abstract: There is disclosed herein a caddie for a chain saw having a saw bar, comprising: at least one wheel, having a rotational axis, for resting upon a supporting surface with the rotational axis substantially parallel thereto; a mounting bracket, supported by the wheel(s), to which the chain saw can be fixedly but removably mounted and oriented in a position in which its saw bar defines and lies in a plane substantially parallel and closely adjacent to the supporting surface; and handlebars, in a fixed relationship to the mounting bracket, for being grasped by a user of the caddie in movement and manipulation thereof.

Abstract: A mobile silvicultural apparatus for use in a land of trees comprising mature trees and immature trees. The apparatus includes a steerable wheeled support frame, an articulated boom, a motor system, and a control system. The steerable wheeled support frame has a horizontally extending ground-clearing section, and first and second opposite vertical side sections. The ground-clearing and side sections define a tunnel-shaped passage through which the immature trees are allowed to pass as the support frame travels thereover. The articulated boom is mounted to the support frame for selectively manipulating the mature trees. The motor system is used for imparting motion to the support frame and the control system is used for controlling the steerable support frame, the motor system, and the articulated boom.

Abstract: A cutting attachment is adapted to be mounted onto a vehicle, such as a skid steer loader, and includes a frame that is generally “V” shaped with diverging walls and open in direction of travel. The diverging walls of the frame support upright shafts. Each of the shafts has a rotating disk on the lower end thereof that has a circular cutting edge. The disks are preferably co-planar and closely adjacent to each other along a center longitudinal axis of the frame, and are not powered. When the disks are moved against standing vegetation with stalks or trunks, they rotate and sever the vegetation. Additionally, a lift plate is provided on the trailing side of the disks so after severing the vegetation the lift plate lifts the trunks of trees or stalks or the like upwardly from the disks. The lift plate is inclined to tend to cause the trees to tilt outwardly. Support arms can be closed to hold the cut tree or other vegetation in the frame until the arms are released.

Abstract: A sawing device and a chain for it, comprising at least two adjacent sequences of connecting links, of which at least some are cutting teeth; and a sequence of drive links fitted between two adjacent connecting link sequences, wherein an opening at the rear end of the drive link is centered at an opening in the front end of the connecting links, wherein an opening in the front end of the drive link is centered at an opening of the rear end of the connecting links, and wherein a binding pin extending through the whole width of the chain is fitted in the openings. To increase the sawing width, a bush ring is fitted between two adjacent connecting link sequences, around the pin, and placed in the opening of the drive link, and on at least one side of said drive link, a collar is fitted whose diameter is formed greater than the opening in said drive link.

Abstract: The two boom members and hydraulic cylinders of a knuckle boom tree harvesting machine are so arranged and proportioned that with a single control movement during reaching and retracting actions the working tool head is made to travel in an approximately horizontal path. The cylinders and control valve are so connected that during horizontal reaching action load-supporting pressurized oil from a collapsing cylinder is not required to be dumped to the reservoir in the conventional heat generating manner, but is rather shunted directly to an extending cylinder where it continues to do useful load support work. Energy waste to hydraulic oil heat and fuel consumption is significantly reduced. Although these advances have been particularly developed for disc saw felling and stroke delimbing of trees they can also be applied to other knuckle boom applications where horizontal reaching is a major function.

Abstract: A tree saw attachment (10) for use with a loader vehicle includes a base frame (11), a generally V-shaped blade assembly (12), a brush guard (13), and a tweezer arm assembly (14). A swingable tweezer arm (29) of the tweezer arm assembly is movable using a hydraulic cylinder (33) to grasp objects against an upper surface of the base frame or the blade assembly. The brush guard and tweezer arm assembly are removable from the base frame as a single unit to facilitate shipping and assembly. A sprayer assembly (90) is positioned within the base frame for applying a herbicide to tree stumps cut by the V-shaped blade assembly. The blade assembly can be a single integral blade (42), or can be formed of right and left blades (70, 71) with intermeshing projections (73, 74) secured to a rib member (36) along a centerline of the blade assembly.

Abstract: A tree harvester head structure is connected to a mounting structure on a mobile tree harvester by a compact coupling which provides lateral pivotal movement of the harvester head structure. An antifriction bearing and a fluid powered rotary actuator have a concentric relationship and are in substantial radial alignment, thus creating a compact design and avoiding additional side loading of the bearing. A brake prevents rotational movement of the tree harvester head structure except when the rotary actuator is operated.