Abstract: In a combination of a sprocket arrangement (128) and a saw chain (16), a sprocket tooth spacing (TI) between consecutive sprocket teeth (40) relates to a drive link spacing between consecutive drive links (30) of the saw chain (16) such that the guide teeth (42) of two or more drive links (30) may enter between a pair of consecutive sprocket teeth (40).

Abstract: Method and an arrangement within a motor saw, having a guide bar, a drive motor unit including with its chassis a drive motor, whose rotatable shaft supports a drive disc, around which a portion of an endless saw chain runs, the saw chain also being adapted with its remaining portions to run along and form the guide bar arrangement with its guide bar and along tracks allotted to side edges directed away from each other. An anchored support plate, a displaceable clamping plate and with an interrelated arrangement in an inactivated position, the end area of the guide bar within a first mode displaces the end area in a direction perpendicular from the plane and from the support plate, and within a second mode displacing the end area and its guide bar in a direction along the plane allotted to the guide bar and out of the inactivated interrelated arrangement.

Abstract: A chainsaw guide bar adapted for carving and shaping a workpiece. In one embodiment, a guide bar includes a mounting end, a distal working end, and an intermediate portion offset from the longitudinal axis defined the mounting end. In one embodiment, the guide bar includes an axially elongated recess providing an unsupported span of chain which is movable between undeflected and deflected positions for contouring a workpiece. The chain is engaged with and supported in a guide rail slot along the top peripheral edge of the guide bar. Various embodiments of the guide bar have an asymmetrical shape. The guide bar may further include an idler sprocket mechanism operable to guide movement of the saw chain along the outer peripheral edge of the guide bar.

Abstract: A guide bar for a chain saw has an elongate main body of steel. The main body has flat sides and upper and lower peripheries defining a guide groove for a saw chain. An elongate window is formed in the main body between the peripheries and is filled with an insert made of a fiber composite material made up of resin and fibers. The fibers are in the direction of the longitudinal axis of the main body. The insert includes a plurality of fiber layers that are bonded with resin. A central layer is formed from a fiber layer and the fibers thereof are at an angle to the longitudinal axis. Two fiber layers having fibers oriented in the direction of the longitudinal axis of the main body are on both sides of the central layer. The inner fiber layers are covered outwardly by a woven fabric.

Abstract: A chainsaw guide bar adapted for carving and shaping a workpiece. In one embodiment, a guide bar includes a mounting end, a distal cutting end, and an intermediate portion offset from the longitudinal axis defined the mounting end. The guide bar may further include an idler sprocket mechanism operable to keep the saw chain engaged with the outer peripheral edge of the guide bar. In other embodiments, the guide bar includes an axially elongated recess providing an unsupported span of chain which is movable between undeflected and deflected positions when carving a workpiece.

Abstract: The invention is directed to a guide bar for a motor-driven chain saw (1) and includes a longitudinally extending flat base body (2) having a peripherally extending guide groove (3) for guiding a saw chain (4). In the region of the direction-changing section (12) of the guide bar (13), the saw chain (4) is partially laterally covered by guide discs (14, 14′), which rotate along with the idler sprocket (16). The guide discs (14, 14′) include radially projecting sections (18) whose number is identical with the number of the teeth (17) of the idler sprocket (16). The tendency to kickback of the motor-driven chain saw is reduced with these constructive measures.

Abstract: A guide bar (1) is provided for a portable handheld work apparatus, such as a motor-driven chain saw or overhead branch cutter, and includes an elongated, flat base body (4) having a peripherally extending guide groove for guiding a saw chain (6). In the region of the direction-changing section (14) at the free tip (13) of the guide bar (1), the saw chain (6) is laterally partially covered by guide discs (17, 18) which rotate with the idler sprocket (19). The guide discs (17, 18) include radially projecting sections (20, 20′). Corresponding radially projecting sections (20) of one guide disc (17) are arranged offset relative to the radially projecting sections (20′) of the other guide disc (18). With this constructive measure, the manipulation of the portable handheld work apparatus is improved.

Abstract: A vibration-isolating member is formed of an elastic material, and has a mounting hole at the center thereof, a large diameter section at an end of the mounting hole, a groove at the periphery of the large diameter section, and a flange. One of a vibration-source-side member and a vibration-receiving member is fitted into each of the large diameter section and the groove. An end opposite from the large diameter section is secured to one of the vibration-receiving member and the vibration-source-side member by a mounting member. Since the inside diameter of the large diameter section is larger than any other part of the mounting hole, either of the vibration-source-side member or the vibration-receiving member and the mounting member can be received. The flange prevents the vibration-isolating member from disengaging from one of the vibration-source-side member and the vibration-receiving member.

Abstract: A chainsaw guide bar includes a bar body and a nose member removably attached to the bar body by an elastic snap-in coupling, eliminating the need for separate fastening elements. The snap-in coupling includes dimples formed in tongues of the nose member, the dimples being received in holes formed in a web of the bar body. The dimpled portions of the tongues are elastically flexible in a thickness direction of the guide bar to enable the nose member to be inserted or removed.

Abstract: The invention relates to a guide bar for a motor-driven chain saw comprising an elongated planar base body which has a guide groove (8) in its outer periphery for guiding a saw chain (6). The saw chain (6) includes cutting links (14), lateral connecting links (12) and center drive links (10). The links are pivotally connected to each other with rivets (18). The drive links (10) engage with rakers (11) in the guide groove (8); whereas, the connecting links (12) are supported on guide surfaces (9) provided laterally of the guide groove (8). The guide bar (3) is fixed to the housing (2) of the motor-driven chain saw (1) at its attachment end (4) and the free tip (22) of the guide bar (3) has a direction-changing section (21) for the saw chain (6). In the region of the direction-changing section (21), guide plates (23, 43) are attached to the guide bar (3).

Abstract: A guide bar (1) is provided for a portable handheld work apparatus, such as a motor-driven chain saw or overhead branch cutter, and includes an elongated, flat base body (4) having a peripherally extending guide groove for guiding a saw chain (6). In the region of the direction-changing section (14) at the free tip (13) of the guide bar (1), the saw chain (6) is laterally partially covered by guide discs (17, 18) which rotate with the idler sprocket (19). The guide discs (17, 18) include radially projecting sections (20, 20′). Corresponding radially projecting sections (20) of one guide disc (17) are arranged offset relative to the radially projecting sections (20′) of the other guide disc (18). With this constructive measure, the manipulation of the portable handheld work apparatus is improved.

Abstract: The invention is directed to a guide bar for a motor-driven chain saw (1) and includes a longitudinally extending flat base body (2) having a peripherally extending guide groove (3) for guiding a saw chain (4). In the region of the direction-changing section (12) of the guide bar (13), the saw chain (4) is partially laterally covered by guide discs (14, 14′), which rotate along with the idler sprocket (16). The guide discs (14, 14′) include radially projecting sections (18) whose number is identical with the number of the teeth (17) of the idler sprocket (16). The tendency to kickback of the motor-driven chain saw is reduced with these constructive measures.

Abstract: A nose sprocket for the saw chain of a chain saw includes radially projecting teeth, each tooth having leading and trailing edges. Each of those edges includes a straight inner portion and an outer portion that deviates from a radius of the sprocket by a greater amount than the inner portion. The teeth are long enough to enter a space formed between side links of the saw chain.

Abstract: An improved nose sprocket which carries central drive links of a saw chain has a gullet shaped to provide ample space for saw dust to collect and reduce stress concentration within the gullet. The nose sprocket has teeth which define a gullet. The gullet has a bottom portion shaped with a varying radius of curvature. The varying radius of curvature is largest at a deepest portion of the gullet and smallest where the bottom portion meets flank portions of the teeth which carry the central drive links.

Abstract: A nose sprocket for a chain saw guide bar, where the bottom part of the teeth or the outermost part of the central region or both have indentations with softly inclined trailing edges, acting as hydrodynamical bearings to keep the sprocket centered between the side plates of the guide bar.

Abstract: A nose sprocket for chain saws includes an inner peripheral surface defining a bearing race, and teeth disposed at an outer peripheral portion of the nose sprocket. Side surfaces of the nose sprocket are provided with a vapor-deposited low-friction coating, except that the inner peripheral surface and a portion of each side surface adjoining the inner peripheral surface are free of the coating.

Abstract: A trimmer which can reduce the size of a section including a lubricating oil pump for automatically supplying a lubricating oil to a saw chain during the drive of the saw chain and drive shaft members for driving the saw chain, and secure good mountability of the section. In the trimmer, a gear unit is mounted to the forward end portion of an operating rod, and a gearcase of the gear unit, a mount base and a seal case are mutually connected toward an output shaft. A regenerative pump includes a stirring chamber defined between the mount base and the seal case, and a tabular grooved rotor which is fitted to a drive shaft to be coaxially connected to the output shaft and which is rotated in the stirring chamber in accordance with the rotation of the output shaft. Lubricating oil discharged from the regenerative pump is supplied to a saw chain through a supply port of the mount base, through-holes of the chain bar, through-slots and a guide groove.

Abstract: A drive sprocket arrangement includes a drive sprocket and a drive ring rolling loosely on the outer periphery of the sprocket. Drive links of the saw chain enter recesses in the sprocket via orifices in the drive ring. The drive ring has at an axial inner edge thereof a radially inwardly directed flange to retain the ring on the sprocket, and at an axial outer edge thereof a radially outwardly directed flange to retain the chain in place. The flanges are arranged such that the axial inner edge will be disposed above the axial outer edge when the drive shaft of the chain saw points downwardly.

Abstract: A chain saw guide bar having two opposed nose plates at the free end thereof. Each nose plate has an outwardly formed impression which faces the outwardly formed impression in the opposed nose plate, to allow a thicker idler roller assembly to be mounted between the outwardly formed impressions. The idler roller assembly includes an inner bearing journal, roller bearings, and an idler roller with a concave groove around its outer circumference, within which groove the drive links of the saw chain track. Two thin shims are placed on opposite sides of the idler roller assembly between the nose plates. A replacement nose assembly is also disclosed which includes two substantially identical outer plates positioned apart a given distance.

Abstract: A chain saw guide bar having two opposed nose plates at the free end thereof. Each nose plate has an outwardly formed impression which faces the outwardly formed impression in the opposed nose plate, to allow a thicker idler roller assembly to be mounted between the outwardly formed impressions. The idler roller assembly includes an inner bearing journal, roller bearings, and an idler roller with a concave groove around its outer circumference, within which groove the drive links of the saw chain track. Two thin shims are placed on opposite sides of the idler roller assembly between the nose plates. A replacement nose assembly is also disclosed which includes two substantially identical outer plates positioned apart a given distance.

Abstract: A sprocket for a chain including a thick hub portion and a plurality of thinner sprocket rings mounted on the hub. The hub has a rounded polygon peripheral configuration and the rings have complementary bores to receive the hub. The rings have sprocket teeth defined about their outer edges. When the sprocket rings are mounted in face-to-face nesting arrangement on the hub the teeth on adjacent sprocket rings are aligned axially of the hub. A pair of side plates having a greater diameter than the sprocket rings confine the rings on the hub and aid in holding a chain thereon during operation.

Abstract: A power take-off system for attachment to the elongated bar of a chain saw. A shaft is rotatably carried by a housing which is attached to the bar of the chain saw. A gear is carried on the shaft and is located in a transverse aperture in the bar such that the gear is driven by the nose sprocket in the bar. The housing serves as a guard over the chain on the bar also. The power take-off system may be provided as a self-contained integral unit which replaces the existing cutting bar on the chain saw.

Abstract: A chain saw bar nose has a rotatable sprocket. The sprocket assembly is adapted to conform in shape to the drive tang portions of the saw chain whereby the nose sprocket may receive operational forces imposed by the saw chain substantially as compressive forces as opposed to tensile forces. As a result, the nose sprocket assembly better withstands the harsh operating conditions imposed by cutting applications.

Abstract: A chain saw has a chain bar (1) with a nose sprocket (5) over which a saw chain (3) circulates. The sprocket (5) is mounted between two nose cheek plates (53). The interior spacing between the plates corresponds to the thickness of the sprocket. The peripheral area of the sprocket with associated teeth at the bar nose extends outside the cheek plates over at least half the sprocket circumference, such that the saw chain passing over the sprocket goes entirely free from the plates and the rest of the bar. Means are arranged for supplying pressurized lubricant via the bar to the sprocket mounting. The lubricant pressure and the gaps between the side surfaces of the sprocket and the inner faces of the cheek plates are such that in operation lubricant passes out through the gaps.

Abstract: A sprocket nose guide bar for guiding an endless saw chain. A configured sprocket is rotatably mounted in the nose of the bar and functions to elevate and transport the saw chain around the nose end. The teeth of the sprocket engage the drive links of the chain to lift the chain off the nose edge as the chain traverses the nose. The tooth tips project above the side link bearing surfaces and into configured notches whereby the teeth effectively provide the lifting action without entering the saw chain chassis.

Abstract: A guide bar for a chain saw with closed oil channels, arranged to lubricate the inside of the chain just before it starts sliding against the underside of the guidebar, as well as the supporting teeth of the nose sprocket just before the intermesh with the chain.

Abstract: A sprocket assembly including a sprocket adapter driven by the motor of a chain saw. The adapter includes an adapter shaft which has a defined inner opening to fit around the drive shaft of the chain saw. A sprocket is mounted on the adapter shaft. Splines on the adapter shaft exterior fit into spline grooves of the sprocket. The thickness at the roots of the splines provide the strength to resist breakage. The exterior areas of the adapter shaft between the splines are flat landings which define relieved thickness areas between the splines and are aligned with tang-receiving pockets in the sprocket. The relieved areas permit an optimum sizing of the sprocket to the saw chain with sufficient pocket depth to fully receive the drive tangs of a saw chain. The sprocket rims are provided with mated inner edges that mate to the flat landings of the adapter shaft to facilitate transmission of the turning power from the drive shaft.

Abstract: A nose roller tip for a cutter bar of a chain saw. There is a mounting web to engage the cutter bar. A pair of rollers are each mounted on opposed sides of the mounting web. There are outer plates, one adjacent each roller. The mounting web, rollers and outer plates are attached together to allow free rotation of the roller relative to the nose roller tip.

Abstract: For motor-driven chain saws, there is the danger that the chain saw will be kicked back if the reaction forces suddenly increase intensely in response to the forward thrust. This kickback effect and the danger of accident associated therewith are intended to be reduced by means of a special configuration of the saw chain. The saw chain has drive links which have an approximately triangular shape and which engage the tooth gaps of the nose sprocket with inclined flanks. The drive links are configured to be asymmetrical with respect to a partition line running between the two pivot axes of the link so that the forward flank angle is greater than the rearward flank angle referred to the partition line. The two flank angles together are greater than the opening angle of the V-shaped tooth gap of the nose sprocket.

Abstract: An arrangement for decreasing the strain on a rivet joint of the top wheel in a motor saw. Lateral forces in consequence of unvoluntary jamming or twisting of the saw chain by its surrounding of the top of the sword cannot be totally avoided, which often gets the rivet joint (17) of the top wheel loose. In order to avoid such a thing it is suggested to provide a releasing slot (19) which separates the chain guiding portion of the outer sheets (10,11) of the saw sword from the riveted portion forming the inner roll bearing surface of the top wheel, which slot is extending through at least 180.degree. thereof.

Abstract: With motor-driven chain saws, there is the danger that the chain saw will be thrown upwardly and rearwardly when it is applied to wood by the user with a forward thrust. Serious injuries can then occur. The invention is directed to a motor-driven chain saw which is so configured that the cutting forces are automatically reduced in response to the occurrence of excessive reaction forces so that the reaction force is immediately reduced to a tolerable amount thereby eliminating the kickback effect. The drive links engaging the nose sprocket of the guide bar are so dimensioned that they can further pivot in the tooth gaps of the nose sprocket out of their normal position and, in this way, take the cutting links with them in such a manner that the free angle of the cutting teeth is reduced. The drive links are latched in the pivoted-in position on the nose sprocket in order to assure that the cutting links will retain the position with the reduced free angle over the entire turnaround region of the guide bar.

Abstract: With motor-driven chain saws, there is the danger that the chain saw will be thrown upwardly and rearwardly when it is applied to wood by the user with a forward thrust. Serious injuries can then occur. The invention is directed to a saw chain which is so configured that the cutting forces are automatically reduced in response to the occurrence of excessive reaction forces so that the reaction force is immediately reduced to a tolerable amount thereby eliminating the kickback effect. The drive links of the saw chain which engage into the nose sprocket of the guide bar are so dimensioned that they can further pivot in the tooth gaps of the nose sprocket out of their normal position and, in this way, take the cutting links with them in such a manner that the free angle .alpha. of the cutting teeth is reduced.

Abstract: A chain saw bar having an elongated shape, a saw chain guideway around substantially the length of the perimeter thereof, with a matching saw chain sprocket in the nose thereof, and calculated points of variation in strength in the interior of the bar at points removed from the sprocket, the points of variation in strength acting so that if the bar is subjected to an excessive bending force, the bar will tend to become bent initially at one point of variation in strength and with increased bending force at a subsequent point of variation in strength. In this way, extreme bending of the bar at one location and pinching of the sprocket are minimized.

Abstract: A chain saw guide bar comprises a guide bar body and a nose assembly coupled to an end of the guide bar body, the guide bar body having a longitudinal tongue projecting centrally from an end thereof and thinner core plates extending laterally from opposite sides of the tongue, the nose assembly being composed of a pair of side plates having recesses defined centrally in tail ends thereof and receiving the tongue fitted therein, the body and the nose assembly being coupled together by rivets inserted through the side plates and the core plates with the core plates inserted between the side plates. The core plates may or may not project beyond a distal end of the tongue. The end of the guide bar body and the tail end of the nose assembly are held in abutment at a position spaced 90 mm or preferably more from a tip end of the nose assembly so that the guide bar body will not be adversely affected by hitting engagement with a saw chain.

Abstract: A chain saw bar having a central groove along the top and bottom edges to guide the chain about the bar, and a bar nose structure at the end of the bar to guide the chain from the top edge to the bottom edge. The nose structure including an extension of the bar on one side of the groove and a roller rotatably mounted on the extension to form the other side of the groove at the nose of the bar. The roller and extension having arcuate peripheral faces to guide the chain about the nose of the bar.

Abstract: Cutting horizontal, cantilevering objects of splittable material, such as de-barked tree trunks and the like is carried out with the aid of a guided, endless circulating saw chain (10), the upper cutting part of which is moved from below and upwards through the object. The lower edge portions of the cut surfaces at the cut are allowed to bear against each other under the action of the bending moment of the cantilevering object, while the return portion of the saw chain in the cutting area is kept free from the cut surfaces. The saw chain is guided by a chain guide (12) extending curvilinearly under the object and guides the return part of the chain. The chain guide and the guided return part are both outside and below the object during the whole of the cutting operation, while the upper cutting portion of the chain runs straight between the end points of the curved portion of the chain guide.

Abstract: Chain saw bar having at its free end a sprocket 20 which supports the saw chain and is rotatably mounted between two side plates (18, 19) in the saw bar on a tubular shaft (26) which is rigidly connected to the sprocket and is adapted to transfer rotation to a driven shaft inserted into the tubular shaft bearing means (24, 25) being arranged in both side plates rotatably supporting the tubular shaft. According to the invention the tubular shaft (26) is short enough to be inserted into a kerf sawed by a saw chain mounted on the saw bar.

Abstract: A chain saw having a saw chain and a chain bar, the saw chain comprising a plurality cutter links interconnected by connector links, the chain saw further having a sprocket or roller mounted for rotation in the plane of the bar adjacent the nose thereof, whereby the saw chain is guided around the nose of the chain bar, the sprocket or roller being shaped to receive driving tongues of the chain such that the cutter links of the chain are guided on a path of small radius than the path of movement of the connector links so that the depth of cut possible by the cutter links is reduced.

Abstract: A stone block, cutting chain saw having an improved drive sprocket and chain link design is disclosed. The sprocket itself is formed using rectangular, preferably square, shaped teeth which engage corresponding receiving areas on the cutting chain. In the preferred embodiment, the teeth are formed of carbide steel. The sprocket having the improved teeth design is rotably attached to a drive shaft. The cutting chain continuously revolves around the drive sprocket and at least a second sprocket, so that rotary motion over both sprockets enables the continuous cutting of stone, rock, coal and the like.

Abstract: A pruning and clearing apparatus comprises a guide bar mounted on a handle. The saw chain of the guide bar is driven by means of a hydraulic motor and a separate portable drive unit comprising a hydraulic pump driven by an internal combustion engine and provided with an oil cooler. The hydraulic pump is connected to the hydraulic motor by lines arranged in the handle.

Abstract: A chain saw guide blade includes a pair of side plates between which an axle is fixedly supported and a sprocket is rotatably supported with respect to the axle. The sprocket is rotatable about the axle with roller bearings therebetween for guiding a cutter chain for movement around the edge of the guide blade. A pair of annular seals are respectively disposed between the sprocket and one of the side plates and between the sprocket and the other side plate. Each of the seals includes an annular lip projecting obliquely into resilient contact with a surface of the sprocket or of one of the side plates. A grease-supply aperture in each side plate is normally closed off by a flap on the annular seal or resilient valve placed in a central hole of the axle. When under the pressure of forced grease through the aperture, the flap or valve is resiliently yieldable to allow the grease to be introduced for the lubrication of the roller bearings.

Abstract: In a segmented bar having a longitudinal axis, a first bar section slidably interengageable with a second bar section under longitudinal axially displacement to move into and out of end to end abutting interlocking mating relation, each of said bar sections presenting corresponding longitudinally extending mating surface formations on opposite sides and corresponding longitudinally extending mating edge formations along opposite edges, each bar section terminating in an abutting end edge formation to be presented to the abutting end edge formation of the other of said bar sections when disposed in interlocking mating relation, the opposed surface formations of one of said sections each including a locating recess therein and offset in relation to each other and each bounded by a portion of the extent of its adjacent abutting end edge formation, the opposed surface formations of the other of said sections each including a mating projection for each of said locating recesses and likewise offset in relation to e

Abstract: A sprocket wheel, bearing and bearing plate of a chain saw guide bar are mounted as a separate unit between the side plates of the guide bar.

Abstract: In a chain saw guide bar which at its free end has a saw chain-supporting sprocket wheel journalled on a hub and surrounded by side plates of the guide bar, the side plates are embossed (shaped) in three concentric zones having progressive embossing depths providing, between the side plate and the sprocket wheel, a gap which progressively increases in width -- either step-by-step or continuously -- with the radial distance from the center of the sprocket wheel.

Abstract: A guide bar for a chain saw having a main body portion that is symmetrical so as to be invertible, i.e., to reverse the top and bottom edges, and including a nose portion having fixed top and bottom positions that is removably attached to the outer end of the main bar portion. Said nose portion is non-symmetrical with the upper quadrant of the nose sharply curved away from the top edge and the lower quadrant gradually curved back to the bottom edge. Whereas the main body portion can be inverted, the life of that portion of the bar is greatly increased.

Abstract: Disclosed herein is a chain saw comprising an elongated cutter bar having, at the outer edges thereof, laterally spaced side rails, together with a curved end portion including laterally spaced side plates and a journalled idler wheel with a peripheral outer surface extending between the side plates and having a plurality of spaced outwardly extending lobes, and an endless saw chain trained around the cutter bar and having pivotally connected side and center links, each of the side links having a bottom surface, which during semicircular traversal of the curved end portion engages one of the side rails to provide partial support for the chain traversing the curved end portion, each of the center links having a lower portion which includes a forward edge extending downwardly between the side rails with at least one of the forward edges being in contact with one of the lobes to insure rotation of the idler wheel during chain traversal of the curved end portion, each of the center link lower portions also having

Abstract: A guide bar for a chain saw including a main bar portion having its outer end edge abutting a mating inner end edge of a nose portion. At least a section of one of the bar portions adjacent the abutting end edges is formed by side plates supported in a spaced apart position by spacing posts. A connecting web connects the bar portions with the said one bar portion fitting between the spaced apart side plates. The web is provided with slots to accommodate the supporting posts and displaceable ear portions extend into the slots to resist but not prevent passage of the posts. Forcing the said one bar portion over the web causes the ear portions to deflect around the supporting posts which then resists but does not prevent separation of said one bar portion from the web.

Abstract: A guide bar has a main portion and a nose portion. The main portion has a convex outer end and the nose portion a mating concave inner end. A tongue extends from the nose portion for insertion in a receiving slot in the main portion and rivets fasten the tongue to the main portion. A relief is formed at the junctions of the edges of the nose portion and main portion, i.e., at the points where the saw chain passes from the main portion to the nose portion and then back to the main portion of the guide bar.