Abstract: An electric motor or gasoline engine driven pruner by which to facilitate the cutting of generally inaccessible or hard to reach trees and shrubs. The pruner includes a rotatable drive shaft, an elongated tubular drive shaft housing surrounding the drive shaft, an electric motor or gasoline engine affixed to one end of the drive shaft housing to rotate the drive shaft, and a cutting head affixed to the outer end of the drive shaft housing to efficiently cut trees and shrubs. A unique arrangement of telescoping, concentrically aligned housing sections surrounds an arrangement of telescoping, concentrically aligned drive shaft sections to permit the pruner to be extended to reach high, and otherwise inaccessible branches and limbs or collapsed to form a compact assembly for easy transport and/or storage.

Abstract: A handle of a portable power-driven machine such as a chain saw has an upper handle member and a lower handle member which are adjoined to each other to present the form of a handle. The handle also has an anti-slip rubber layer lining the outer surface of the lower handle member. The rubber layer has an upper end folded back on the upper ends of both side walls of the lower handle member to overlie the upper inner periphery of the lower handle member. The upper handle member has vertical downward projections which engage the folded end portion of the rubber layer overlying the upper inner periphery of the lower handle member.

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: An adapter having particular application to quickly and easily convert a portable worm driven circular power saw into a sprocket driven chain saw. The adapter comprises an adjustable compression ring portion which is adapted to be attached to the existing bearing plate of the circular saw without requiring a removal of the bearing plate. Coextensively formed with the adapter compression ring portion is a base portion having a structure which permits a cutting chain bar and a cutting chain safety guard to be connected to opposite faces of the base portion. Thus, a circular cutting blade may be replaced by a cutting chain, and vice versa, without removing the existing bearing plate, as is commonly required when a conventional converison apparatus is utilized.

Abstract: This disclosure relates to a guide bar for a saw chain which includes a pair of side plates and a center plate laser welded to and between the side plates. The center plate has a peripheral edge which is spaced inwardly from the outer periphery of the side plates so as to form a peripheral guide channel or groove for the chain. The disclosure further relates to a method of making a three-plate guide bar wherein the plates are laser welded together.

Abstract: A carburetor chamber cover device for covering a carburetor chamber of a portable power-driven machine such as a chain saw. The carburetor chamber accommodates an air cleaner and a carburetor for supplying air-fuel mixture to an internal combustion engine. The cover device comprises a cover adapted to close the opening of the carburetor chamber and having an aperture, and a filter plate and a blind plate adapted to be selectively attached to the cover so as to fit the aperture. The filter plate has a screen capable of arresting comparatively large particles of dust. In order to avoid troubles such as blocking of the filter plate by snow or icing of the carburetor, the filter plate is detached and the blind plate is attached instead.

Abstract: A length-measuring attachment for a chain saw includes a clamp assembly for mounting a transversely-extending measuring arm to the chain saw handle. A slidably mounted resilient index pointer is connected to the arm for marking the appropriate length of a piece of wood to be cut. The resilient pointer flexes enabling cuts to be made at any point along the piece of wood and serves to indicate proper plane of cut as well as proper length.

Abstract: A device is disclosed to make slits through the bark of a log with a chain saw. The chain saw has a blade with a chain which runs over its extreme free end which is preferably semicircular in shape. Rotatable guide rollers are mounted on both sides of the extreme end of the blade and are preferably coaxial with the semicircular end. The lateral surfaces of the guide rollers face each other and guide rollers in operation hold the chain of the chain saw in contact with a log to be cut for cutting slits of a given depth through its bark.

Abstract: A guide bar extension member coupled to a guide bar of a chain saw for selectively lengthening or shortening the cutting bar for cutting different size pieces of timber, for example. In its preferred form, the guide bar comprises a sectional guide bar assembly which is separable at the high point of its curved periphery into rear and forward guide bar portions with an extension element of a predetermined length inserted therebetween.

Abstract: An improved speed reduction drive for an electric chain saw is disclosed. The speed reduction drive comprises a first rotatable member directly driven by the drive shaft of the electric motor for rotation therewith. A second rotatable member is connected to the drive sprocket for the cutter chain for rotation in the same direction. At least one endless drive loop drivingly connects the first and second rotatable members for rotation in the same direction, whereby rotational inertia of the electric motor opposes "kickback" of the chain saw.

Abstract: Saw gage involving a retractable scale tape and a magnetic means for retaining it on a chain saw.

Abstract: A chain saw gauging attachment having a fitting at one end adapted to be received under an existing nut on an existing stud of a chain saw, a rod extending outwardly from the fitting, means for firmly attaching the rod to the fitting, and an indicator which is slidably affixed to the rod and adapted to be fixed in predetermined positions. The fitting of the gauging attachment may be provided with a rotating means which permits the gauging attachment to be swung to the rear of the chain saw and away from the working area when not in use. When mounted, the gauge rod extends along the length of the work piece of a log to which is to be cut, and the indicator of the gauge rod enables the user to fix by sight the place on the log where the next cut is to be made. The gauge rod is slender and resilient whereby it will spring back to its original shape if accidently flexed.

Abstract: The present invention comprises a pair of wheels mounted on a stub shaft, the outer surfaces of the wheels being bevelled to facilitate entering into a kerf. The wheels are mounted in a slot formed in the blade of a woodcutting implement which carries the cutting teeth.

Abstract: A chain saw attachment for mounting on a portable power-driven chain saw having a saw bar and an endless saw chain disposed for movement around the saw bar, the chain saw attachment consisting of: (a) a cutting head assembly including a first wheel having a central axial aperture and slots in the perimeter of the wheel for receiving four cutting knives; a second wheel having a central axial aperture and slots in the perimeter of the wheel for receiving four cutting knives; a drive sprocket positioned between the two wheels, the drive sprocket being adapted to receive and be driven by the chain; eight cutting knives, the cutting knives being individually positioned in the slots in the perimeters of the first and second wheels and held in the slots by set screws; and three bolts for holding closely together in a unitary assembly the first and second wheels and the drive sprocket; (b) an axle extending through the central axial apertures of the first and second wheels, the ends of the axle extending normally out

Abstract: Disclosed is a safety handle that is rotatively mounted on the existing front handle of the chain saw and is operatively connected to the existing on-off switch to independently actuate such switch to shut off the engine and stop the cutting chain upon rotation of such safety handle to its "off" position either automatically when kick-back occurs or upon such rotation by the human operator at his option. A wrist guide struck by the human operator's hand during severe kick-back or when the chain saw is dropped similarly rotates the safety handle to its "off" position. An automatic reset mechanism restores the safety handle to its "on" position after the safety handle has been rotated to its "off" position and released.

Abstract: A cutting attachment for a chain saw which substantially reduces the problems of kickback, lubrication and maintenance, is described. The attachment comprises a guide bar, a saw chain and a drive sprocket. The guide bar is smoothly and symmetrically convexly curved along both its longitudinal edges with a first radius of curvature and is provided with a nose portion with a second and smaller radius of curvature. The edge of each of the cutter and balancing links in contact with the bar is provided with two curved surfaces, one surface having a radius of curvature corresponding to the radius of curvature of the nose portion of the bar, and the other surface having a radius of curvature corresponding to the radius of curvature of the longitudinal edge of the bar. The height of the cutter links is chosen in relation to the length of the cutter to prevent rearing of the cutter links.

Abstract: A housing for a chain saw which is a clamshell type having a support section and a cover section. The cover section has a lower section which is at least three times wider than the width of the support section. The cover section has stiffening ribs formed on the underside of the wide lower section. Fastening means enterconnect the support section and the cover section.

Abstract: A chainsaw attachment for indicating a sawing point on a workpiece, having a support having at least two arms with grip portions clampable to the chain guide bar of the chainsaw for holding a rule substantially perpendicular to the plane of sawing with the end of the rule opposite a reference point on the workpiece. The support shown comprises two independently formed arms positioned on opposite sides of the chain guide bar, connected by a threaded connector and arranged to pivot about a fulcrum to tightly engage the chain guide bar. Each arm shown has a hole in one end slightly larger than the rule, a grip portion on the other end, and a fulcrum region between the hole end and the grip portion so arranged that when the threaded connector is tightened, the fulcrum regions bear against one another, the grip portions are drawn together to clamp the support to the guide bar, and the hole ends are forced apart causing the hole perimeters to bind against and hold a rod-form rule firmly in a selected position.

Abstract: A chain saw has a motor, a cutting chain and a guide bar for the chain. An opening is formed in the guide bar. A flexible bladder is positioned in the opening and located on the guide bar. Fluid can be inserted into the bladder so that the bladder may be expanded. The expanded bladder can topple a cut tree without the necessity of removing the chain saw from the tree.

Abstract: An attachment for a chain saw, suitable for holding a work length gauge, such as a wire log length gauge, to the chain saw so as to facilitate measuring and cutting logs to equal length, is provided for fastening to different handles and/or handle portions of different types of chain saws and for holding the gauge in desired gauging position with respect to the saw chains and cuts. The attachment is adapted to be fastened to vertical, horizontal transverse and horizontal longitudinal handle portions and to hold the log length gauge so that it may extend horizontally and transversely with respect to the chain. Positioning of the attachment on the saw may be effected by removing or loosening the saw handle and sliding the attachment onto it and then refastening the handle. In a preferred embodiment of the invention the attachment may be fastened to the saw handle without the need for loosening or removing the handle.

Abstract: A chain saw safety brake mechanism includes an actuating drum rotatably disposed around the periphery of a clutch drum and a brake band wound around the clutch drum at least one convolution and hooked at one of its ends its other actuating drum and attached to the other end to a chain saw body. A spring is provided for turning the actuating drum from its ready position to a brake actuating position in which the brake band is tightened around the clutch drum to arrest its rotation. A reset lever is provided on the actuating drum to turn it to the ready position thereby producing a spring force in the spring.

Abstract: A portable motor chain saw with a safety braking device to protect against kick-back, recoil or centrifugal movements of the saw. The saw includes a handle supported against the motor housing by damping elements, and also includes a locking device which on the one hand is connected with the handle, and on the other hand engages against a hand guard in such a way that it is released under the influence of relative movement, of the motor housing with respect to the handle, caused by a kick-back or centrifugal movement, consequently releasing the hand guard. The locking device has an abutment surface extending transverse to the direction of centrifugal movement, and this abutment surface cooperates with a projection directed against it.

Abstract: A power transmission device adapted to be employed with a chain saw for providing a rotary output in a plurality of directions. The device includes a housing having an input shaft coupled with an output shaft where the input and output shafts are right angles to one another. The housing serves as the support for the driven mechanism and provides mounting flanges about both the input and output shafts. The mounting flange associated with the input shaft cooperates with a chain guideplate to adjustably mount the housing to the chain saw. By simply loosening two screws, the orientation of the output shaft relative to the chain saw can be changed by up to substantially 180 degrees. The mounting flange around the output shaft is designed to allow a 360-degree range in orientation of the driven device about an axis coincident with the axis of the output shaft.

Abstract: A housing for an internal combustion engine of the type used with portable chain saws having a cavity therein for a fuel supply and another cavity for lubricating oil. The engine housing is composed of at least an upper and a lower portion which are joined along a substantially horizontal dividing plane which is substantially parallel to the bottom plate of the lower portion of the engine housing. The dividing plane intersects the crankshaft casing of the engine whereby two separate closed cavities are formed for separately storing fuel and lubricating oil for said chain saw.

Abstract: The invention is concerned with the reduction of the vibration transmitted from a mechanism having at least one element rotating at a fundamental frequency and one or more cyclically displaceable further elements connected to said rotating element, and in which the displacements of said further elements produce an aggregate cyclic linear exciting force of fundamental frequency and harmonics thereof acting on the same line. To prevent transmission of vibrations produced by said exciting force from the mechanism to its support means, the mechanism is constrained to prevent all degrees of freedom of movement relative to the support means except for movement under the influence of said linear exciting force which is thereby isolated from the support means. The mechanism also has balancing means integral with or attached to said rotating element for balancing any rotating force produced at said fundamental frequency.

Abstract: A blade device for motor-driven cutter instruments has a one-piece cutter bar with a smooth external edge, a sprocket wheel, an endless chain with chain links which meshes with the sprocket wheel and is guided on the cutter bar, and aligned with its central plane narrow, sharpened cutting elements on the outside of the chain links. One type of chain link is a slider which slides on the external edge of the cutter bar and has a lagging zone which meshes with the sprocket wheel and two passage holes arranged close to its base. The second type of chain link is two opposed trapezium-shaped very thin laminae on both sides of the cutter bar, with corner zones which cover the passage holes in the slider and two pins rigidly laser-connected, which pass through the passage holes.

Abstract: An accessory device is provided for securement to a conventional portable type chainsaw to define a fixed predetermined distance of the cutting plane of the saw from an end of a work to be cut. With this arrangement, successive cuts of identical lengths can be rapidly made. The accessory itself comprises a plurality of straight cylindrical tubes nested in telescoping relationship and with appropriate frictional engagement with each other. With this arrangement, any desired length can be defined by the extent of telescoping of the tubes and the defined lengths remain fixed as a consequence of the friction between the tubes. This fixed length can thus be used for successively measuring off equal cuts of a log or other wood to be cut by the chainsaw and the operator need not be concerned with further adjustments until such time as the successive cuts are to be changed in length.

Abstract: Excavating apparatus including a boom having an idler pulley on its outer end and adapted to carry a digging chain in sliding arrangement with the boom is provided with skid shoe means and a nose piece which are disposed between the idler pulley and the outer end of the boom for slidably engaging and supporting the digging chain between the idler pulley and the lower surface of the boom. The skid shoe means defines a support surface that is substantially coplanar with the lower surface of the boom to support the links of the chain, and the nose piece has a lower surface generally parallel to the lower surface of the boom and is adapted to engage the digging chain rollers when the links of the chain are engaging the skid shoe means. Both the skid shoe means and the nose piece thus prevent the chain from causing excessive wear on the end of the boom.

Abstract: An improved guide bar for a chain saw having two sawdust kick-out holes in the rear of the guide bar. Each kick-out hole passes completely through the guide bar and through a guide groove in the bar. Also provided are at least two lubricating holes in the guide bar which extend through the bar and guide groove. The lubricating holes are straight holes transverse to the guide groove with a countersunk portion at the outer edge thereof, and the lubricating holes are designed to communicate with a lubricating means in the chassis of the saw, so that lubricating oil can be supplied into the guide groove. Also provided is a special sawdust plate designed to fit between the bar and the chassis of the saw.

Abstract: An endless chain of this invention for a chain saw is provided with cutter links of a unique shape and construction. Such cutter link has an inclined U-shaped and substantially consists of a saw adjusting portion and a saw tooth portion. The saw tooth portion further has a hard metal tip brazed at the top thereof, wherein the hard metal tip forms a saw set. Due to such construction, the saw tooth portion which is provided with such hard metal tip can smoothly saw off lumber while the saw adjusting portion can completely remove the sawn-off lumber chips. The saw adjusting portion also provides minimum vibration of the chain saw.

Abstract: A chain saw gauging attachment comprising an elongate, slender gauge rod having at one end a fitting with a bore adapted to receive said end, and means for firmly attaching the rod to the fitting. The fitting has a threaded bore aligned with the first bore and adapted to be threaded onto the protruding portion of an existing stud of the chain saw frame, so as to extend laterally from the latter and from the chain track. As thus mounted, the gauge rod extends along the length of a work piece or log which is to be cut, and the free end of the gauge rod enables the user to fix by sight the place on the log where the next cut is to be made. A knurled periphery of the fitting facilitates its being screwed onto the existing threaded stud. The gauge rod is slender and resilient, whereby it springs back to its original shape if accidentially flexed. The rod can be cut to a desired length, and can have a bend at its free end to facilitate the designating of the place for the next saw cut.

Abstract: A portable gas-motor-driven cutting implement has a motor unit combined with a fuel tank and supporting a tool carrier. The cutting implement is provided with a curved front handle member extending substantially transversely of the tool carrier and a rear handle at the rear of the motor unit. The front handle member and the rear handle form parts of a rigid, closed supporting frame connected to the motor unit by three widely spaced resilient members, two of which are arranged at the front of the motor unit while the third is arranged at the rear of the motor unit.

Abstract: A spring action guide bar stop for portable power chain saw is located adjacent the saw housing near where the chain returns to the housing to absorb and dampen vibration during operation of the saw. The spring stop is preferably a leaf spring coiled into a loop so that the side of the loop contacts the object being cut with friction dampening being obtained by providing frictional contact between the ends of the spring loop.

Abstract: A guard member is mounted on the chain saw for swinging movement between an actuate position and a reset position. The guard member occupies a normal position between the actuate and reset positions. A brake band is integral with a bowed column spring which applies the braking force to arrest movement of the cutting chain. A latching mechanism includes an arm with a latch pin engaged by a yieldable latch finger; this latch finger is integral with the bowed column spring. The guard member deflects the latch finger in response to movement of the guard to its actuate position; this action allows the column spring to apply the brake. The guard member is moved to its actuate position in response to a sudden movement of the chain saw, as in the case of "kickback"; this movement of the guard member is brought about by inertia or the engagement of the guard with the operator's body (most likely the wrist or the back of his hand) during this abrupt movement of the chain saw.

Abstract: A method and apparatus for removing entrained matter from the intake air of a chain saw internal combustion engine of the type including at least one piston and cylinder, a crank shaft, and a carburetor.The apparatus includes a shroud surrounding at least one end of the crank shaft with an air inlet fashioned into the shroud at a position adjacent to said one end of the crank shaft and an air outlet fashioned into the shroud at a position remote from the air inlet. An air passage opens into the shroud adjacent the crank shaft for providing fluid communication between the interior of the shroud and the carburetor. The crank shaft is provided with a hub having on opposite faces thereof a first and second cascade of radial flow compressor blades to centrifugally impel air and entrained particulate matter away from the crankshaft. The compressor blades serve to remove at least a portion of the entrained matter from the combustion inlet air prior to the air entering the air passage for delivery to the carburetor.

Abstract: A portable chain saw includes a flexible brake band for stopping the cutter chain. A sensing arm is pivotally mounted on the chain saw housing, with the brake band being connected to this sensing arm. The sensing arm is arranged to be engaged by an arm or hand of an operator so as to be swung forwardly in a brake-tightening manner. The sensing arm is continuously biased forwardly to a braking position by a coil compression spring. A latch normally holds the sensing arm in a rest position. The latch comprises a metallic strip one end of which is fixedly secured to the housing. The other end of the strip has a bent configuration defining a notch for receiving a curved projection of the sensing arm to retain the latter. The strip extends forwardly from the housing in overlying position above the spring and projection.

Abstract: A clutch arrangement for a motor driven chain saw having a first clutch element driven by the motor shaft and a second clutch element normally engaged with the first clutch element but disengageable therefrom and a centrifugal clutch between the second clutch element and the drive sprocket for the saw chain. The second clutch element includes a spring disc and is axially yieldable between clutch engaged and clutch disengaged positions. A lever is provided moveable for disengaging the clutch elements and a brake member connected to the lever is operable for braking the drive sprocket when the clutch elements are disengaged.

Abstract: A portable motor chain saw with a guiding rail structure which on at least a portion of its circumferential surface on which the saw chain is slidably guided has a semicircular head by which the chain is deviated while a reinforcing layer of Stellite is applied on the region of the deviating portion of the guiding rail structure, the Stellite together with the adjacent guiding rail portion being tempered.

Abstract: Disclosed herein is a chain saw comprising a chain sprocket rotatably supported by a frame and driven by an engine supported by the frame, a sprocket guard supported from the frame, a cutter bar having an end supported between the frame and the sprocket guard in spaced relation from the sprocket, together with a first guide plate supported between the frame and the cutter bar and including a main part, and a guide portion extending from the main part and including a first part extending in generally parallel and laterally outwardly offset relation with respect to the cutter bar and a second part diverging laterally outwardly from the first part, and a second guide plate supported between the sprocket guard and the cutter bar and including a main part, and a guide portion extending from the second guide plate main part and including a first part extending in generally parallel and laterally outwardly offset relation with respect to the cutter bar, and a second part diverging laterally outwardly from the first

Abstract: A motor chain saw with a driving sprocket wheel adapted to be driven by a motor through the intervention of a centrifugal clutch, or the like. A safety clutch is arranged in the driving connection between the motor shaft and the driving sprocket and disengageable by a release mechanism. The safety clutch includes at least one disengageable follower member for interconnecting the two pertaining clutch members while being coaxially arranged with the centrifugal clutch and being located adjacent thereto. The safety clutch is arranged on that side of said centrifugal clutch which faces toward the driving sprocket while being located in the driving connection between the centrifugal clutch and the driving sprocket.

Abstract: An engine unit enclosing an engine, a fuel tank, an oil tank and a chain driving system is mounted on a handle assembly consisting of a front handle, a rear handle and a handle connecting member interconnecting the front and rear handle and supporting the bottom of the engine unit through three vibration isolators made of an elastic material. The rear end of the handle connecting member is joined through a vibration isolator to the rear end of the rear handle, and the front upper end of the rear handle is joined through vibration isolator to the top of the engine unit. The upper end of the front handle is positioned in parallel with the upper end of the rear handle in the horizontal direction and joined thereto through a vibration isolator, and the lower end of the front handle is joined directly to the front end of the handle connecting member.

Abstract: A device for automatically actuating a band brake on a motor saw for emergency stopping of the saw chain, wherein a latching mechanism including pretensioned elastic force-providing coupling is released, occurring upon a throw movement of the saw, by a pin or the like transferring a force between a carrying handle of the saw and a collapsable arm of the mechanism.

Abstract: A chain saw safety brake including a snap-acting, over-center actuating mechanism.A chain saw safety brake and method of operation characterized by an actuation accelerator interposed between a brake mechanism and a brake actuating mechanism. A biasing means is operable to bias the brake actuating means toward a nonactuating position with a relatively lower biasing force. The biasing means is operable to bias the brake actuating means toward an actuating position with a relatively higher biasing force.

Abstract: A saw chain guide device for a chain saw in which an end face of each of side plates disposed adjacent to a drive sprocket of the saw chain terminates extremely adjacent to a tooth tip circle of the drive sprocket of the saw chain, and an edge portion extending beyond the end face and along the tooth tip circle of the toothed sprocket is integrally formed with at least one of the side plates confronting outerside of the chain saw.