US3839795A - Chain saw safety method and apparatus - Google Patents
Chain saw safety method and apparatus Download PDFInfo
- Publication number
- US3839795A US3839795A US00354776A US35477673A US3839795A US 3839795 A US3839795 A US 3839795A US 00354776 A US00354776 A US 00354776A US 35477673 A US35477673 A US 35477673A US 3839795 A US3839795 A US 3839795A
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- US
- United States
- Prior art keywords
- disc
- cam
- chain saw
- driving
- chain
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27B—SAWS FOR WOOD OR SIMILAR MATERIAL; COMPONENTS OR ACCESSORIES THEREFOR
- B27B17/00—Chain saws; Equipment therefor
- B27B17/08—Drives or gearings; Devices for swivelling or tilting the chain saw
- B27B17/10—Transmission clutches specially designed for chain saws
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27B—SAWS FOR WOOD OR SIMILAR MATERIAL; COMPONENTS OR ACCESSORIES THEREFOR
- B27B17/00—Chain saws; Equipment therefor
- B27B17/08—Drives or gearings; Devices for swivelling or tilting the chain saw
- B27B17/083—Devices for arresting movement of the saw chain
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/04—Processes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/869—Means to drive or to guide tool
- Y10T83/8878—Guide
Definitions
- a disc means fixedly connected to the sprocket and operably engageable with the clutch means in a driving relationship.
- Means are provided for biasing at least a portion of the disc into operable driving engagement with the clutch means.
- a cam means is connected within the housing and is operably engageable with the disc.
- An actuation system is connected to the housing for actuating the cam against the disc in response to at least one of an abrupt upward pivot or kick of the guide rail generally aboutthe center of gravity of the chain saw and physical engagement of at least a portion of the actuation system by an operators hand slipping from theframe handle. Actuation of this system serves to overcome the bias and disengage the disc from driving engagement with the clutch to thus remove driving torque from the cutting chain.
- An independent apparatus aspect of the invention is r
- the method includes the steps of providing a disc fixedly connected to the cutting chain drive sprocket,
- the method further includes providing a cam operably carried for rotation within the chain saw housing and being engageable with the disc and actuating the cam in response to at least one of an upward pivot or kick of the guide rail generally about the center of gravity of the chain saw, and physical engagement of at least a portion of the actuating system by an operators hand slipping from the frame handle for overcoming the bias on the disc and disengaging the disc from driving engagement with the clutch to remove driving torque from. the sprocket and cutting chain.
- This invention relates to a chain saw safety method and apparatus. More particularly the invention relates to a method and apparatus for minimizing the possibility of an operator being injured'in the event of a kickback phenomena which tends to pivot the cutting chain toward an operator or the occurrence of an operators hand slipping from a frame handle of the chain saw toward the chain saw cutting chain.
- a chain saw is designed to be utilized by an operator grasping the machine with both hands.
- An operators one hand normally grips a frame handle while the other hand engages a control handle for at least actuating a trigger throttle mechanism of the type suitable for ultimately controlling the speed of the cutting chain.
- the cutting chain may engage a green limb or the like at the tip of the guide bar.
- vertical movement of the cutting chain over the guide bar nose may induce the bar to violently kick upwardly in a manner commonly referred to as kickback.
- the abrupt action of kickback may cause an operators hand to slip from the frame handle into the cutting chain or pivot the cutting chain generally about the center of gravity of the chain saw into the operators arm or chest.
- an operator may choose to apply downward and forward pressure on the frame handle to achieve a more rapid cutting rate. In such event there is at least a possibility of the operators hand slipping from the frame handle toward and potentially into the rapidly moving cutting chain. Experience indicates that if an operators hand does accidentally engage the rapidly moving cutting chain, the hand may be badly mutilated and/or possibly severed.
- a preferred embodiment of the invention intended to accomplish at least some of the foregoing objects comprises a method and apparatus for preventing injury to an operator of a chain saw of the type having a housing including a frame handle and a control handle, a guide rail connected to the housing, a cutting chain operably carried by the guide rail.
- power means mounted within the housing including a drive shaft operably connectable with the cutting chain, sprocket means meshed in driving engagement with the cutting chain and clutch means at least in part connected to the drive shaft and operable for selectively connecting the drive shaft and the clutch means for driving the cutting chain.
- the apparatus includes in combination with the foregoing described chain saw a disc means fixedly connected to the sprocket and operably engageable with the clutch means in a driving relationship. Means are provided for biasing at least a portion of the disc into operable driving engagement with the clutch means. A cam means is connected within the housing and is operably engageable with the disc. An actuation system is connected to the housing for actuating the'cam against the disc in response to at least one of an abrupt upward pivot or kick of the guide rail generally about the center of gravity of the chain saw and physical engagement of at least a portion of the actuation system by an operators hand slipping from the frame handle. Actuation of this system serves to overcome the bias and disengage the disc from driving engagement with the clutch to thus remove driving torque from the cutting chain. v
- An independently significant apparatus aspect of the invention is the provision of an inertia actuation system for operably disengaging a chain saw drive shaft from a cutting chain in the event an abrupt upward pivot or kick of the guide rail generally about the center of gravity of the chain saw is encountered.
- the method includes the steps of providing a disc fixedly connected to the cutting chain drive sprocket,
- the method further includes providing a cam operably carried for rotation within the chain saw housing arid being engageable with the disc and actuating the cam in response to at least one of an upward pivot or kick" of the guide rail generally about the center of gravity of the chain saw, and physical engagement of at least a portion of the actuating system by an operator's hand slipping from the frame handle for overcoming the bias on the disc and disengaging the disc from driving engagement with the clutch to remove driving torque from the sprocket and cutting chain.
- FIG. I is an axonometric view of a hand held portable chain saw wherein an operator may grasp a frame handle with one hand and a control handle with the other hand for manipulation and operation of the saw.
- the frame handle is broken away to disclose an exterior view of a safety apparatus comprising the subject invention
- FIG. 2 note sheet 2 is a cross-sectional detailed view of the safety apparatus including a disc spring connected to a chain sprocket and operably engaging studs within a chain saw clutch.
- a cam is carried by the chain saw housing in a posture coaxial with the clutch which is axially translatable by a cowl and bell crank actuation system;
- FIG. 3 is a detailed end elevational view of the spring disc extending between the chain sprocket and the centrifugal clutch;
- FIG. 4 is a partially broken away side elevational view disclosing the sloping camsurfaces of the camming member
- FIG. 5, note sheet 1. is an axonometric view of the cylindrical sleeve cam member including a pair of sloping cam surfaces; Y
- FIG. 6, note sheet 3. is a side elevational detailed view of a cowl and bell crank operably engaged and biased together in a posture prior to actuation;
- FIG. 7, note sheet I, is a cross-sectional view taken along section line 7-7 in FIG. 6;
- FIG. 8 note sheet 3, is a side elevational detailed view of the cowl and bell crank following actuation of the safety apparatus;
- FIG. 9, note sheet I, is a detailed cross-sectional view taken along section line 99 in FIG. 8;
- FIGS. 10A-C disclose schematic views of a first and second spring disc according to a preferred embodiment of the invention wherein the spring strength of .both discs are substantially the same and disengagement of the first disc with a clutch drum entails bending of both discs in series;
- FIGS. llA-B disclose an alternate preferred embodiment of the invention wherein the spring strength of the second disc is much greater than the spring strength of the first disc engaged with the clutch drum and upon actuation of the disengaging cam total flexing, sufficient to disengage the first disc from the clutch drum, is provided by the first disc;
- FIGS. 12A-B disclose a further alternate preferred embodiment of the invention wherein the spring strength of the second disc is much less that the spring constant of the first disc connected to the clutch drum and upon actuation of the disengagement cam total flexing, sufficient to disengage the first disc from the clutch drum, is provided by the second disc.
- a portable chain saw 20 having a chain saw housing 22 including a frame handle 24 and a control handle 26.
- a guide rail 28 is releasably connected by threaded fasteners to the housing 22 and serves to carry an endless cutting chain 29.
- the chain saw further includes an internal combustion engine, preferably of the small one or two cylinder two stroke type (not shown), which serves to torque a driving shaft 30, note FIG. 2.
- the drive shaft 30 is connected to a centrifugal clutch 32 to supply driving torque to a sprocket 34 which in turn meshes in driving engagement with the endless cutting chain 29.
- the clutch 32 includes a driving hub 36 which is releasably mounted upon the drive shaft 30 by a threaded fastener 38. Coaxially surrounding the drive shaft and hub is a clutch drum 40 which is mounted for free rotation upon the drive shaft 30 by a bearing 42.
- the hub 36 is drivingly connected to the clutch drum or driven member by the provision of a plurality of radially exwith the present invention, reference may be had to U.S. Hazzard Pats. Nos. 3,429,41 l issued Feb. 25, 1969, and 3,477,555 issued Nov. 11, 1969, and US. Henry Pat. No. 3,640,365 issued Feb. 8, 1972. The disclosures of these patents are hereby incorporated by references as though set forth at length.
- a chain saw of the type described above is designed to be hand held by an operator using one hand to grasp the frame handle and the other hand to engage the control handle.
- Cutting manipulation of the saw is typically achieved by utilizing the control handle as a fulcrum and applying guiding'pressure to the frame handle. It will readily be appreciated, however, that in applying a forward pressure upon the frame handle that an operators hand may potentially slip toward and into the rapidly moving cutting chain 29 Alternatively, a kickback phenomenon may be encountered where the nose of the cutting bar engages a green limb and tends to violently kick upward, pivoting the saw generally about its center of gravity toward the operator.
- the subject invention is specifically designed to obviate or minimize injuries precipitated by kickback of the cutting bar toward an operator or an operators hand accidentally slipping from the guide frame handle.
- the clutch drum 40 is mounted for free pivotal rotation about the drive shaft 30 by a sleeve bearing 42.
- a second bearing 50 is concentrically mounted upon the drive shaft and sleeve bearing 42 and provides freepivotal'rotationof the drive sprocket 34 with respect to the clutch drum'40 and drive shaft 30.
- a first spring disc 52 forming an integral part of the subject invention, provides selective connection between the clutch drum 40 and the chain sprocket 34.
- the disc 52 is fashioned with an inner hub portion 54 which is fixedly connected or bonded to a radial face of the chain sprocket 34, note FIG. 2.
- a plurality of spring spokes 56 radiate from the hub 52 and are connected at the free ends thereofby a peripheral outer rim 58.
- the radial extent of the spokes 56 are such that the peripheral outer rim 58 lies slightly radially beyond the outer periphery of the centrifucal clutch drum 40, note FIG. 2.
- a plurality of studs 60 are mounted within a radial face of the clutch drum 40 and generally axially project toward the spring disc 52.
- the spokes 56 of the spring disc are normally inclined toward the clutch drum, note FIG. 2 and serve to self bias the disc into engagement with the radial face of the clutch drum 40 with adjacent ones of the plurality of radially extending spokes 56 lying upon opposite sides of the studs 60.
- stud engaging lands 62 are fashioned at an appropriate radial location upon each of the spokes 56 to abut against. in driving relationship, the studs 60.
- the cutting chain sprocket 34 is mounted for free rotation upon the drive shaft by the provision of a sleeve bearing 50.
- This bearing in turn is free to axially translate back and forth with respect to the drive shaft 30 but is biased toward the clutch drum 40 by the provision of a second spring disc 64 extending between the chain sprocket 34 and a thrust bearing 65.
- a cylindrical sleeve cam 66 is coaxially mounted'about the drive shaft 30 in a posture contiguous to but spaced'from the outer rim 58 of the first spring disc, note FIG. 2.
- the cam sleeve 66 is provided with a cylindrical body portion 68 and a first end edge 70 formed by a plane extending normal to the axis of the cylinder 68.
- a second end edge 72 is fashioned with a pair of slop posture of abutting contact suitable to overcome the bias of the first and second spring discs, note FIG. 9.
- a longitudinally extending tab is integrally fashioned within the cam 66 and projects through an arcuate slot 82 within the housing 22, note FIGS. 7 and 9.
- the free end of tab 80 is received within a well 84 of a rotatable cowl 90.
- the cowl comprises a cylindrical member 92.
- cowl 90 which is pivotally mounted upon housing 22 coaxially with respect to the drive shaft 30. More specifically the cowl 90 is mounted within an aperature 94 of the housing 22 by the provision of an inwardly projecting cylinlong arm 104 and a short arm 106.
- the bell crank is pivotally mounted upon thechain saw frame 22 as at 108.
- the short arm 106 of the bell crank 102 is fashioned with an outwardly projecting dog 110 which is operatively receivable within a compatibly dimensioned detent 112 fashioned within the outer peripheral surface of the cowl 90.
- the cowl 90 is biased for clockwise rotation as seen in FIG. 6 by the provision of a coil tension spring 114
- the tension of spring 114 in the set or ready posture depicted in FIG. 6 may be adjusted by appropriate location of the connecting pin 120 within a sloping slot 122, fashioned within the short arm 106 of the bell crank.
- a radially projecting hand lever 124 is provided which is integrally fashioned with the cowl 90.
- an inertia mass 130 is mounted generally at the free end of the long arm.
- the inertia mass 130 may be comprised of a plurality of designs, such as merely a weight radially adjustably connected directly to the long arm 104, not shown.
- a U-shaped bar 130 is provided which normally projects with respect to the free end of the bell crank in a generally parallel posture in front of the frame handle 24.
- the inertia of the long arm 104 of the bell crank and the inertia mass 130 is operable in the event of an abrupt kickback or upward pivotal movement of the guide bar 28 about the center of gravity of the chain saw to release the dog 1 10 from detent 1 l2 and actuate the subject safety assembly.
- the bar 130 will be directly engaged to actuate the subject safety system and further positively block engagement of the operators hand with the cutting chain.
- the dog 110 In response to at least one of an abrupt upward pivot or kick of the guide rail 28 generally about the center of gravity C. G. of the chain saw and physical engagement of at least a portion of the actuation assembly, such as by an operators hand slipping from the frame handle into the U-shaped bar 130, the dog 110 will raise and be'released from frictional engagement with the detent 112. The tension spring 114 will then rotate the cowl 90 in a clockwise direction as viewed in FIG. 6 into a posture depicted in FIG. 8.
- the chain sprocket 34 is connected to the clutch drum 32 by the provision of a first disc assembly 52 and is further biased toward the clutch drum 32 by the provision of a second disc spring 64.
- the axial distance of travel at the outer periphery of the first spring and the second spring is a function of the design spring constants or strengths of each of the springs. Three embodiments of varying spring strengths are depicted in FIGS. 10-12, note sheet 4.
- the spring strength of the first spring disc is slightly greater than, although approximately equal to, the spring strength of the second spring disc. Accordingly, as depicted in the sequence of FIGS. 10A, 10B and 10C, axial translation of the cam 66 serves to flex in series the spring disc 52 and 64 in order to remove the spokes 56 of the first disc from driving engagement with the studs 60. While the actual spring constants of the first and second discs may be varied over a considerable range, it is preferred in most instances that the spring strength of the first disc remain greater than the spring strength of the second disc.
- FIGS. 1 lA-B disclose an alternate preferred embodiment of the invention wherein the spring strength of the second disc 64 is substantially greater than the spring strength of the first disc 52. As a result of this relative spring constant rate. the entire flexing action of the spokes 56 out of engagement with the stud 60 is provided by the first disc 52.
- FIGS. l2A-B A further alternate preferred embodiment of the invention is depicted in FIGS. l2A-B wherein the spring strength of the first disc 52 is substantially greater than the spring strength of the second disc 64.
- the sprocket 34 translates with respect to the drive shaft 30 and fully deflects spring 64 to remove the first need not be designed with any resiliency at all and relatively non-resilient materials may be utilized.
- a principal advantage of the invention resides in the method and apparatus for minizing the possibility of injury to a chain saw operator in the event of kickback during a cutting operation.
- This principal advantage is achieved through the provision of a novel actuationv system comprising an inertia mechanism which is responsive to the occurrence of normal kickback phenomena during a cutting operation.
- Another major advantage of the invention resides in the extremely rapid response of the actuation system and disengagement of driving torque on the cutting chain. This responsiveness is achieved upon kickback safety lever against the chain saw frame handle or,con-
- a housing including,
- a frame handle, and a control handle a guide rail connected to said housing; a cutting chain operably carried by said guide rail; power means mounted within said housing including,
- sprocket means meshed in driving engagement with said cutting chain
- clutch means at least in part connected to said driv shaft, operable for selectively connecting said drive shaft and said sprocket means for driving said cutting chain;
- cam means connected to said housing and operably engageable with said disc means
- said disc means comprises,
- a hub connected to said sprocket; a plurality of resilient spokes radiating from said hub, and v p a peripheral outer rim connecting the outer ends of said spokes, and said clutch means comprises,
- a cylindrical sleeve rotatably mounted within said chain saw housing and being coaxially disposed about said clutch means, including at least one sloping cam surface; and at least one cam ramp fashioned within said housing for engagement with said at least one sloping cam surface to axially translate said cylindrical sleeve upon rotation of said cam means wherein, said axial translation of said cylindrical sleeve serves to engage an outer rim of said disc means'and disengage said disc means from driving engagement with said clutch means.
- a chain saw as defined in claim'3 wherein: said cylindrical sleeve being fashioned with a pair of sloping cam surfaces each extending approximately about the periphery of one end of said cylindrical sleeve; said housing being fashioned with a pair of cam ramps for engagement with said pair of sloping cam surfaces; and a tab longitudinally extending upon said cylindrical sleeve at a junction of the pair of sloping cam surfaces for connecting said cam means with said actuation means.
- said actuation means comprises:
- a lever pivotally connected to said housing including an integral dog
- a bell crank with said dog being fashioned upon a short arm thereof and an inertia mass connected to the long arm thereof.
- a chain saw as defined in claim 5 wherein said lever comprises:
- a bell crank with said dog being fashioned upon a short arm thereof and a guard bar normally extending from the free end of a long arm thereof generally parallel to said frame handle and between said frame handle and said cutting chain.
- a housing including,
- sprocket means meshed in driving engagement with said cutting chain
- clutch means at least in part connected to said drive shaft, operable for selectively connecting said drive shaft and said sprocket means for driving said cutting chain;
- first spring disc means fixedly connected to said sprocket means and being self biased against and operably engageable with said clutch means in a driving relationship;
- second spring disc means positioned between a thrust bearing and said sprocket means for biasing said sprocket toward said clutch means;
- cam means connected to said housing and operably engageable with said disc means
- actuation means connected to said housing for actuating said cam means against said first disc means in response to at least one of an abrupt upward pivot of said guide rail generally about the center of gravity of the chain saw and physical engagement of at least a portion of said actuation means by an operators hand slipping from said frame handle in order to overcome the serially combined bias of said first and second disc means and disengage said first disc from driving engagement with said clutch means to thus remove driving torque from said cutting chain.
- the spring strength of said second disc is generally similar to the spring strength of said first disc whereby upon actuation of said cam against said first disc said first and second spring disc means will flex in series to disengage said first disc from said clutch means.
- the spring strength of said second disc is substantially greater than the spring strength of said first disc whereby disengagement of said first disc from said clutch means is achieved without substantially flexing said second spring dlSC.
- a housing including,
- a frame handle, and a control handle a guide rail connected to said housing; a cutting chain operably carried by said guide rail; power means mounted within said housing including,
- sprocket means meshed in driving engagement with said cutting chain
- clutch means including a driving hub connected to said drive shaft, a driven drum freely pivotally mounted upon said drive shaft, and clutch shoe means carried by said driving hub and being operable to selectively connect said driving hub with said driven drum;
- a hub portion connected to said sprocket, a plurality of resilient spokes radiating from said hub and being normally inclined toward said clutch drum, and a peripheral outer rim connecting the outer ends of said spokes;
- said resilient spokes of said spring disc means being operable to self bias said spring disc means against said clutch drum with adjacent ones of said plurality of resilient spokes extending on opposite sides of respective ones of said plurality of driving lugs whereby driving torque is operably transmitted to said disc means through said driving lugs;
- At least one arcuate cam ramp coaxially fashioned within said chain saw housing adjacent said clutch drum;
- a cylindrical sleeve cam rotatably mounted within said chain saw housing between said spring disc and said at least one arcuate cam ramp and coaxially about said clutch drum including a first end edge cut by a plane extending normal to the axis of said cylindrical sleeve, said first end edge extending contiguous to but spaced from said peripheral outer rim of said spring disc, and
- a second end edge fashioned with at least one sloping surface operably compatible with said at least one arcuate cam and extending contiguous thereto whereby rotation of said cylindrical sleeve cam will cause said at least one sloping cam surface to ride up said at least one arcuate cam ramp and axially translate said sleeve cam against said peripheral outer rim of said spring disc to disengage said plurality of radially extending spokes from driving engagement with said plurality of driving lugs; a generally cylindrical cowl pivotally mounted upon said chain saw housing coaxially with said clutch drum and being connected to said cylindrical sleeve cam whereby rotation of said cowl effectuates corresponding rotation of said cylindrical sleeve cam, said cowl being provided with a detent in the outer periphery thereof; V a bell crank having a short leg and a long leg and being pivotally mounted upon said chain saw housing adjacent said cowl and including a dog fashioned upon the short leg of said bell crank and being operable to engage with said detent in said cowl
- a chain saw as defined in claim 12 wherein said biasing means connected between said bell crank and said cowl comprises:
- a helicial tension spring having one end at least partially wrapped around the outer periphery of said cowl and being fixed thereto by a pin extending within said cowl and having the other end connected by a pin to the short leg of said bell cranes.
- a chain saw as defined in claim 12 wherein said means connected to the long leg of said bell crank comprises:
- a power means mounted within said housing including,
- sprocket means meshed in driving engagement with said cutting chain
- cam means connected to said housing and engageable with said disc means
- actuating means connected to said housing and being operable to actuate said cam means against said disc means and disengage said disc means from driving engagement with said clutch means wherein said method comprises the steps of:
- a housing including,
- a frame handle, and a control handle a guide rail connectedto said housing; a cutting chain operably carried by said guide rail; power means mounted within said housing including,
- sprocket means meshed in said cutting chain
- clutch means at least in part connected to said drive shaft, operable for selectively connecting said drive shaft and said sprocket means for driving said cutting chain;
- a bell crank pivotally mounted upon said chain saw housing and having a short arm thereof operably connected to said means for engaging and disengaging and a long arm thereof fitted with an inertia mass at the remote end thereof for actuating said means for engaging and disengaging to operably disengage said drive shaft fromsaid cutting chain in response to an abrupt upward pivot of said guide rail generally about the center of gravity of the chain saw.
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Abstract
Description
Claims (26)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00354776A US3839795A (en) | 1973-04-26 | 1973-04-26 | Chain saw safety method and apparatus |
DE19742417828 DE2417828A1 (en) | 1973-04-26 | 1974-04-11 | SAFETY DEVICE FOR CHAINSAWS |
JP49045191A JPS5013996A (en) | 1973-04-26 | 1974-04-23 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00354776A US3839795A (en) | 1973-04-26 | 1973-04-26 | Chain saw safety method and apparatus |
Publications (1)
Publication Number | Publication Date |
---|---|
US3839795A true US3839795A (en) | 1974-10-08 |
Family
ID=23394862
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00354776A Expired - Lifetime US3839795A (en) | 1973-04-26 | 1973-04-26 | Chain saw safety method and apparatus |
Country Status (3)
Country | Link |
---|---|
US (1) | US3839795A (en) |
JP (1) | JPS5013996A (en) |
DE (1) | DE2417828A1 (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3937306A (en) * | 1973-08-29 | 1976-02-10 | Husqvarna Ab | Automatic brake actuator for a chain saw |
US3958680A (en) * | 1973-12-22 | 1976-05-25 | Andreas Stihl Maschinenfabrik | Motor chain saw with plural clutches and a brake |
US3991864A (en) * | 1973-10-25 | 1976-11-16 | Andreas Stihl Maschinenfabrik | Motor saw, especially motor chain saw |
US4140209A (en) * | 1973-10-25 | 1979-02-20 | Andreas Stihl Maschinenfabrik | Motor saw, especially motor chain saw |
US4213521A (en) * | 1976-12-22 | 1980-07-22 | Warner Electric Brake & Clutch Company | Clutch-brake assembly for rotary implements |
FR2481986A1 (en) * | 1980-05-12 | 1981-11-13 | Kioritz Corp | SAFETY BRAKE MECHANISM FOR MECHANICAL CHAIN SAW |
FR2482511A1 (en) * | 1980-05-17 | 1981-11-20 | Stihl Andreas | CHAINSAW ENGINE SAW |
US4446954A (en) * | 1980-11-03 | 1984-05-08 | Andreas Stihl | Centrifugal clutch for power saws |
US4573556A (en) * | 1983-05-20 | 1986-03-04 | Aktiebolaget Electrolux | Actuator for the release of an automatic emergency brake of a hand-operated powered tool |
EP0940233A2 (en) * | 1998-03-06 | 1999-09-08 | Black & Decker Inc. | Clutch mechanism for a chain saw |
US6564459B1 (en) * | 1999-07-07 | 2003-05-20 | Robert Bosch Gmbh | Chain saw |
US20080016705A1 (en) * | 2006-07-19 | 2008-01-24 | Kai-Ulrich Machens | Portable handheld work apparatus |
US20140290074A1 (en) * | 2013-03-29 | 2014-10-02 | Makita Corporation | Portable working machine |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS5645745B2 (en) * | 1973-11-06 | 1981-10-28 |
Citations (5)
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US3339596A (en) * | 1964-12-07 | 1967-09-05 | Outboard Marine Corp | Chain saw |
US3519037A (en) * | 1967-06-14 | 1970-07-07 | Omark Industries Inc | Saw chain driving apparatus |
US3664390A (en) * | 1969-10-29 | 1972-05-23 | Jonsereds Fabrikers Ab | Safety means for power-driven chain saws |
US3739475A (en) * | 1971-10-19 | 1973-06-19 | Mc Culloch Corp | Chain saw safety method and apparatus |
US3776331A (en) * | 1971-04-13 | 1973-12-04 | Partner Ab | Brake-device for power saws |
-
1973
- 1973-04-26 US US00354776A patent/US3839795A/en not_active Expired - Lifetime
-
1974
- 1974-04-11 DE DE19742417828 patent/DE2417828A1/en active Pending
- 1974-04-23 JP JP49045191A patent/JPS5013996A/ja active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
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US3339596A (en) * | 1964-12-07 | 1967-09-05 | Outboard Marine Corp | Chain saw |
US3519037A (en) * | 1967-06-14 | 1970-07-07 | Omark Industries Inc | Saw chain driving apparatus |
US3664390A (en) * | 1969-10-29 | 1972-05-23 | Jonsereds Fabrikers Ab | Safety means for power-driven chain saws |
US3776331A (en) * | 1971-04-13 | 1973-12-04 | Partner Ab | Brake-device for power saws |
US3739475A (en) * | 1971-10-19 | 1973-06-19 | Mc Culloch Corp | Chain saw safety method and apparatus |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3937306A (en) * | 1973-08-29 | 1976-02-10 | Husqvarna Ab | Automatic brake actuator for a chain saw |
US3991864A (en) * | 1973-10-25 | 1976-11-16 | Andreas Stihl Maschinenfabrik | Motor saw, especially motor chain saw |
US4140209A (en) * | 1973-10-25 | 1979-02-20 | Andreas Stihl Maschinenfabrik | Motor saw, especially motor chain saw |
US3958680A (en) * | 1973-12-22 | 1976-05-25 | Andreas Stihl Maschinenfabrik | Motor chain saw with plural clutches and a brake |
US4213521A (en) * | 1976-12-22 | 1980-07-22 | Warner Electric Brake & Clutch Company | Clutch-brake assembly for rotary implements |
FR2481986A1 (en) * | 1980-05-12 | 1981-11-13 | Kioritz Corp | SAFETY BRAKE MECHANISM FOR MECHANICAL CHAIN SAW |
US4328617A (en) * | 1980-05-12 | 1982-05-11 | Kioritz Corporation | Safety brake mechanism for power chain saws |
FR2482511A1 (en) * | 1980-05-17 | 1981-11-20 | Stihl Andreas | CHAINSAW ENGINE SAW |
US4446954A (en) * | 1980-11-03 | 1984-05-08 | Andreas Stihl | Centrifugal clutch for power saws |
US4573556A (en) * | 1983-05-20 | 1986-03-04 | Aktiebolaget Electrolux | Actuator for the release of an automatic emergency brake of a hand-operated powered tool |
EP0940233A2 (en) * | 1998-03-06 | 1999-09-08 | Black & Decker Inc. | Clutch mechanism for a chain saw |
EP0940233A3 (en) * | 1998-03-06 | 2002-01-02 | Black & Decker Inc. | Clutch mechanism for a chain saw |
US6564459B1 (en) * | 1999-07-07 | 2003-05-20 | Robert Bosch Gmbh | Chain saw |
US20080016705A1 (en) * | 2006-07-19 | 2008-01-24 | Kai-Ulrich Machens | Portable handheld work apparatus |
US20140290074A1 (en) * | 2013-03-29 | 2014-10-02 | Makita Corporation | Portable working machine |
US9573208B2 (en) * | 2013-03-29 | 2017-02-21 | Makita Corporation | Portable working machine |
Also Published As
Publication number | Publication date |
---|---|
DE2417828A1 (en) | 1974-11-21 |
JPS5013996A (en) | 1975-02-13 |
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Legal Events
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AS | Assignment |
Owner name: MCCULLOCH CORPORATION A MD CORP. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BLACK & DECKER INC., A DE CORP.;REEL/FRAME:004134/0336 Effective date: 19830505 |
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Owner name: MCCULLOCH CORPORATION, A CORP. OF MD. Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:CITICORP NORTH AMERICA, INC., FORMERLY KNOWN AS CITICORP INDUSTRIAL CREDIT, INC.;REEL/FRAME:005365/0004 Effective date: 19900530 Owner name: FIRST UNION NATIONAL BANK OF NORTH CAROLINA ONE F Free format text: SECURITY INTEREST;ASSIGNOR:MCCULLOCH CORPORATION;REEL/FRAME:005337/0736 Effective date: 19900530 |