US3861374A - Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine - Google Patents
Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine Download PDFInfo
- Publication number
- US3861374A US3861374A US364318A US36431873A US3861374A US 3861374 A US3861374 A US 3861374A US 364318 A US364318 A US 364318A US 36431873 A US36431873 A US 36431873A US 3861374 A US3861374 A US 3861374A
- Authority
- US
- United States
- Prior art keywords
- energy
- gear
- operable
- spring
- engine
- 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
Links
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000002485 combustion reaction Methods 0.000 title claims description 20
- 230000007246 mechanism Effects 0.000 claims abstract description 76
- 238000006243 chemical reaction Methods 0.000 claims abstract description 71
- 239000007858 starting material Substances 0.000 claims abstract description 47
- 238000004146 energy storage Methods 0.000 claims description 39
- 230000004044 response Effects 0.000 claims description 33
- 238000004804 winding Methods 0.000 claims description 32
- 230000000694 effects Effects 0.000 claims description 21
- 238000009825 accumulation Methods 0.000 claims description 19
- 238000003860 storage Methods 0.000 claims description 16
- 230000005540 biological transmission Effects 0.000 claims description 7
- 230000000977 initiatory effect Effects 0.000 claims description 5
- 241000239290 Araneae Species 0.000 description 8
- 230000006870 function Effects 0.000 description 8
- 238000005520 cutting process Methods 0.000 description 6
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 241000282472 Canis lupus familiaris Species 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000012217 deletion Methods 0.000 description 1
- 230000037430 deletion Effects 0.000 description 1
- 230000000881 depressing effect Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000002828 fuel tank Substances 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
- F02N3/00—Other muscle-operated starting apparatus
- F02N3/02—Other muscle-operated starting apparatus having pull-cords
Definitions
- ABSTRACT A lightweight chain saw including a starting mechanism for starting the saw while the saw engine is cold and a restarting mechanism for restarting the saw while the saw engine is warm.
- a method and apparatus for rewinding a starter spring characterized by a starter energy generating system which is continuously engaged with a starter spring and by a friction clutch which is continuously engaged with and operable to disable a reaction device in order to divert energy away from the starter spring.
- this invention is concerned with a unique concept which enables a restarting mechanism to be effectively employed in extremely lightweight chain saws, without significantly increasing the bulk or weight of such chain saws.
- the invention is also concerned with a unique restarting control mechanism which prevents overstressing of an engine restarting spring and which eliminates the necessity for disengaging an engine from a restarting spring winding means when winding has been completed.
- the net result of the invention is to improve and extend the utility of portable chain saws and increase operator safety.
- a principal object of the invention is to provide a lightweight chain saw including a restarting mechanism which is light in weight, which does not create significant bulk or size, yet which is extremely reliable in operation.
- Another principal object of the invention is to provide a starting system for an internal combustion engine, particularly of the type used in portable chain saws, where a recoil starter is employed to effect the starting of a cold chain saw engine while a small restarter mechanism is employed to effect the restarting of a warm chain saw engine.
- Yet another object of the invention is to provide methods and apparatus, as heretofore noted, which eliminate the necessity for engaging and disengaging components in a starter spring rewinding system in order to prevent overstressing of the starter spring.
- a further object of the invention is to provide methods and apparatus, of the type heretofore noted, by means of which an operator may selectively adjust the level of energy stored in a starting system for the purpose of effecting restarting of an engine.
- the internal combustion engine is started while the engine is cold and below a normal operating temperaturev Thereafter an amount of energy is stored sufficient to restart the engine. This amount of energy is sufficient to restart the engine when it is warm and at the normal operating temperature. However, the amount of energy is relatively small, and generally not sufficient to start the engine when it is cold and substantially below a normal operating temperature.
- This minimized amount of stored energy is later used to restart the engine when it is warm and at a normal operating temperature.
- Another independently significant method aspect of the invention is directed to a technique for restarting an engine, particularly an engine of the type used in chain saws.
- a generating means which is continuously operable to mechanically generate engine restarting means.
- the energy generated by this generating means is stored in energy storing means until an amount of energy has been accumulated which is sufficient to start the engine when the engine is warm and at a normal operating temperature, but which is insufficient to start the engine when it is cold.
- This slip clutch means is maintained in continuous frictional but yieldable engagement with the reaction means. Additionally, the energy generating means is maintained in continuous engagement with each of the energy storage means and the reaction means so as to effect an automatic diversion of energy from the storage means, through the reaction means and slip clutch means, without requiring engagement or disengagement of moving parts.
- a third, independently significant, aspect of the invention which is particularly significant in the context of a portable chain saw, entails indicating and adjusting systems relating to the energy storage means.
- a means for indicating that the storage means has not received an amount of energy from the generating means sufficient to restart a warm engine. Additional indicating means provide an operator with an indication that the storage means has received an amount of energy sufficient to effect engine starting.
- a slip clutch means is maintained continuously operable to enable an operator to selectively adjust the level of restarting energy accumulated or stored in the system.
- a uniquely significant apparatus aspect of the invention relates to a combination of first and second gear means, with one of the gear means being coupled with a restarter spring winding arrangement and the other gear means being associated with an energy diverting mechanism.
- a slip clutch means incorporated with the latter gear means automatically serves to effect a diversion of energy from the restarter spring to an energy diverting mechanism without requiring any coupling or decoupling action of drive train components.
- FIG. 1 comprises a fragmentary, perspective view of a lightweight chain saw in which the starting concept of the present invention is embodied;
- FIGS. 2 provide a fragmentary transverse sectional view of a recoil starting mechanism and a restarting mechanism incorporated in the FIG. 1 chain saw, as viewed along section line 22 of FIG. 1;
- FIG. 3 provides an enlarged, transverse sectional view of the FIG. 2 assembly, as viewed along section line 3-3 of FIG. 2, and illustrating in end elevation a slip clutch mechanism which provides an adjustable energy diverting function;
- FIG. 4 provides an enlarged transverse sectional view of the FIG. 2 assembly, as viewed along section line 44 of FIG. 2, and illustrating a centrifugally responsive coupling between a starting shaft and a chain saw engine flywheel assembly;
- FIG. 5 provides a transverse sectional view of the FIG. 2 assembly, illustrating a ratchet-type, recoil mechanism incorporated in the starter portion of the FIG. 2 assembly;
- FIG. 6 provides an end elevational view of spider mechanism incorporated in the FIG. 2 assembly, which spider mechanism serves to provide partial support for a starting and restarting shaft and also provides pivotal support for a restarter actuating, lever mechanism;
- FIG. 7 provides a fragmentary and end elevational view of the FIG. 2 assembly, as viewed along direction 77 of FIG. 2, and illustrating the method of pivotal mounting of a restarter controlling or actuating lever;
- FIG. 8 provides a transverse sectional view of the FIG. 2 assembly, as viewed along section line 88 of FIG. 2, and illustrating certain structural and operational relationships between the actuating lever of FIG. 7 and a restarter spring tripping lever and torque transmitting clutch mechanism;
- FIG. 9 provides an exterior view of the FIG. 2 assembly, as viewed generally along view direction 9-9, and illustrating components of an indicating mechanism which serves to visually reflect the level of energy accumulated in the restarter mechanism.
- This application entails the incorporation of a warm engine restarting mechanism in a lightweight chain saw, which may weigh on the order of 5 or 6 pounds, or less OVERALL STRUCTURE Major components of the chain saw restarter concept of the present invention are illustrated in FIG. 1.
- a chain saw 1 in which the present invention is incorporated comprises a guide bar 2 supporting an articulated, cutter chain 3.
- the guide bar 2 extends from a housing 4.
- This housing 4 contains an internal combustion engine, normally a small, two-cycle engine.
- a suitable drive system contained within housing 4 drivingly connects this engine with the cutter chain 3, possibly through a centrifugal clutch-type torque transmitting mechanism.
- Housing 4 also contains a fuel tank 5, a carburetor assembly, and possibly other chain saw accessories such as oiling mechanisms, etc.
- the chain saw 1 is supported by a handle assembly 6 which includes a longitudinally extending portion 7 and a transversely extending stabilizing portion 8.
- a throttle trigger 9 may be pivotally mounted on handle portion 7. This throttle trigger serves to permit the operator to use the hand grasping handle portion 7 to control chain saw operating speeds.
- Saw 1 also includes a starter and restarter assembly 10 and a control switch 11.
- the starter assembly 10 includes independently operable components designed to effect cold engine starting and warm engine starting.
- Switch 11 is movable longitudinally of housing 4 and serves, in one position; to terminate engine operation by interrupting the ignition circuit of the engine. Switch 11 may be operated by a hand of an operator engaged with either handle portion 7 or handle portion 8.
- flywheel 12 As shown in FIG. 2, is mounted on an engine drive shaft 13. As shown in FIG. 4, flywheel 12 may also provide a plurality of engine cooling fan blades 14.
- An engine starting and restarting shaft 15 isjournaled in housing 4 and may be rotatably supported by a spider frame 16 and a roller bearing assembly 17.
- Starter shaft 15 is well known in structure and, as shown in FIGS. 2 and 4, includes a cylindrical terminus 18 provided with a series of eircumferentially spaced and longitudinally extending slots 19.
- Flywheel 12 may be provided with a plurality of, and as illustrated two, dogs or pawls 20. Each such dog or pawl 20 is pivotally supported on flywheel 12 by a pivot pin 21.
- each such spring 22 includes a helical coil portion 22a encircling its associated pivot pin 21.
- One end 22b of each such spring abuttingly engages an abutment portion of flywheel 12.
- Another end portion 22c is secured in a pawl aperture 20d and serves to bias the lug end 20e toward axis X.
- Each pawl may have an end 20b which abuttingly engages a fan vane 14 to limit the inward movement of pawl end 20e to the position shown in FIG. 4.
- the flywheel 12 will attain a sufficient operating speed so as to cause the eccentrically weighted pawl ends 20a to move radially outwardly in response to centrifugal force, so as to automatically disengage the running engine from the starting and restarting shaft 15.
- counterclockwise engine starting torque (viewing the apparatus in FIG. 2 from its right end) may be imparted to shaft 15 by either of two starter mechanisms incorporated in starting assembly 10.
- the first of these starter mechanisms which will be used to effect starting of the chain saw engine when the engine is cold, comprises a now well-known recoil starter assembly or mechanism 23.
- restarting may be effected by a restarter mechanism 24.
- normal operating temperature is used in a broad sense to include the wide range of temperatures of a chain saw engine which are encountered during the period of time that a chain saw is in use.
- normal operating temperature encompasses operating temperatures while the engine is running and the somewhat reduced temperatures which result when operation of the chain saw is interrupted for a brief period of time during normal cutting operations. Such interruption occurs, for example, when an operator needs to change either his position or the position of the saw.
- recoiol starting mechanism 23 The function of recoiol starting mechanism 23 is to initiate the operation of the chain saw engine when an operator first commences the use of the saw and the engine is cold, i.e. at an ambient temperature substantially below a normal operating temperature. After the saw has once been started, the operator may initiate rcstarting of the saw, when he has momentarily interrupted cutting operations, by operation of the restart mechanism 24.
- An indicating means 25, shown generally in FIGS. 2 and 9, enables an operator to determine the degree of operability of the restarter mechanism 24.
- an operator may adjust the level of energy stored by the restart mechanism 24 for the purpose of effecting engine restarting.
- This adjustment of the level of stored energy to be used for engine restarting may be effected by operator manipulation of an energy level accumulation determining means 26, shown generally in FIG. 3.
- starter assembly 23 Details of starter assembly 23 are shown in FIGS. 1, 2, 4 and 5.
- Recoil starter assembly 23 includes a sheave-type wheel 27 which is journaled on starter shaft 15.
- Sheave 27 is secured in position on shaft 15 by a snap ring 28 engaging the left end of sheave 27, as shown in FIG. 2.
- the right end of sheave 27, shown in FIG. 2 may be secured by an annular housing wall 29 which encircles shaft 15 and is fixedly carried by a cylindrical housing portion 30 of the spider assembly 16.
- a conventional, spiral wound, recoil spring 31 is disposed radially between shaft 15 and cylindrical housing wall 30.
- One end 31a of spring 31 is secured to housing wall 30, while the other end 31b is secured to a generally cylindrical sheave base wall 27a.
- spider mechanism 16 comprises a hub 16a within which shaft 15 is journaled.
- a series of arms 16b radiate generally outwardly of hub 16a in an inclined fashion, as shown in FIG. 2, so as to provide support for the cylindrical wall means 30.
- Radial tab portions of the spider 16 provides collars or eye portions 16d which receive mounting pins 16e, one of which is schematically shown in FIG. 2. These mounting pins are threadably secured to internal boss portions of the housing means 4 so as to effectively anchor the spider assembly 16 to the housing means 4.
- one radiating tab 16c includes a transversely extending aperture 16f. This aperture receives a pivot pin 71 associated with an actuating lever 70, to be subsequently described.
- Sheave 27 also includes a radially extending and outwardly opening cavity 32 which receives a conventional, spirally-wound, pull cord 33.
- Pull cord 33 has, at its outer end, a conventional pull handle 134, as shown in FIG. 1.
- the innermost extremity 33a of pull cord 33 may be secured by a knotted end passing through a sheave aperture 27a.
- Pull cord 33 is wound on sheave 27 such that a pull on handle 34, which induces counterclockwise rotation of sheave 27 (viewing the apparatus from the right end of FIG. 2) and unwinding of the pull cord, will concurrently cause stressing or spiral winding of the spring 31 so as to generate a sheave restoring and pull cord rewinding force.
- a plurality of (as shown, two) dogs or pawls 34 may be pivotally carried by pivot pins 35 projecting from the left end of sheave 27 as shown in FIG. 3.
- Outer extremities 34a of pawls 34 are biased generally radially inwardly by spring assemblies 36, generally shown in FIGS. 2 and 5.
- Each such spring assembly includes a leg portion 36a having a bent extremity 36b engaging an aperture 34b of a pawl 34.
- a helical coil portion 36c of each spring 36 is mounted on the pivot pin 35, while another leg portion 36d of the spring is disposed in abutting or otherwise secured engagement with an abutment pin 37.
- the stressing of each spring 36 is such as to produce a tendency to separate its leg portions 36d and 36a, and thereby cause its associated pawl end 34a to move away from its associated abutment pin 37 which is fixedly mounted on the sheave 27.
- the biasing arrangement associated with each pawl 34, causes a pawl abutment portion 34c to be biased into ratcheting engagement with a ratchet portion 15a of shaft 15.
- This ratcheting portion comprises a series of circumferentially spaced, starter shaft openings 38, as shown generally in FIG. 5.
- the abutment portions 340 of the pawls 34, shown in FIG. 5, are operable, when sheave 27 rotates clockwise relative to shaft 15 as shown in FIG. (counterclockwise viewing the right end of FIG. 2), to engage abutment edges 39 on the edges of shaft slots 38 and thereby induce clockwise movement of the starter shaft 15.
- Such clockwise movement of the sheave 27 and starter shaft 15, as shown in FIG. 5, will be effected in response to pulling on the handle 134 and will serve to induce engine starting.
- the flywheel pawls 20 will be disposed in driven engagement with the shaft end 18 so as to permit engine starting in response to rotation of the sheave 27.
- the centrifugally induced outward movement of the pawls 20 will disengage the engine from the starting shaft so that the shaft 15 will remain stationary during normal engine operation.
- shaft 15 to ratchet in a clockwise direction (as shown in FIG. 5) relative to sheave pawls 34 will ensure that any engine induced rotation of shaft 15 will not damage mechanism 23.
- restarter mechanism 24 RESTARTER MECHANISM AND ITS MODE OF OPERATION Structural and operational details of restarter mechanism 24 will be described with reference to components of this mechanism shown in FIGS. 2, 3, 7 and 8.
- An overwind prevention system associated with a restarter spring which is characterized by continuous coupling between components such that engagement and disengagement problems are avoided.
- Restarter mechanism 24 includes a spring winding shaft 40, shown for example in FIG. 2.
- Shaft 40 carries at its left end, as shown in FIG. 2, a polygonally cross-sectioned socket 41. Socket 41 is matingly engaged, in torque transmitting engagement, with a threaded polygonal nut 42 which is secured on a threaded end 13a of engine shaft 13.
- Nut 42 serves to secure flywheel 12 on shaft 13.
- the shaft 40 serves as a part of a generating means 43 which is con tinuously operable to generate restarting energy.
- shaft 40 is supported at its left end by nut 42 and supported at its rightmost end by a roller bearing assembly 44, Roller bearing assembly 44, in turn, is supported in a cavity 45 of housing 4.
- Generating means 43 in addition to including the shaft 40', comprises a pinion or drive gear 46 and a planetary gear assembly 47.
- pinion gear 46 is fixedly connected to shaft 40 by a transverse pin 48.
- Planetary gear assembly 47 comprises a radially extending arm or body 49 which is journaled on a housing carried, roller bearing assembly 50 for rotation about axis X.
- Arm 49 at its radial ends, rotatably supports planetary gears 51 and 52.
- Each of the planetary gears 51 and 52 is disposed in driven engagement with pinion gear 46.
- Each of the gear portions 51 and 52 of the planetary gear assembly 47 is disposed in continuous meshing engagement with an energy storage means 53.
- This energy storage means 53 comprises a radially inwardly facing ring gear 54 disposed in meshing engagement with planetary gears 51 and 52.
- Ring gear 54 is carried by a generally cylindrical restarter spring housing or case 55 which is journaled on the exterior of shaft 15.
- a spiral-wound, restarting spring 56 is radially interposed between a cylindrical extremity 57 of housing 55 and shaft 15.
- the outermost end of the spring 56 is secured to rotatable spring housing portion 57.
- the radially inner end of spring 56 is secured to a spring arbor 58.
- Spring arbor 58 is thus interposed radially between the spring 56 and the shaft 15.
- arbor 58 may comprises a cylindrical body portion 59 which is journaled on a cylindrical body or base portion 60 of housing 55 and to which the inner end of spring 56 is attached.
- Arbor 58 may also comprise a generally radially extending wall portion 61 which serves to confine the left side of the spring 56, the right side of spring 56 being confined by spring case 55.
- Arbor wall 61 includes spring mounting pin means 62.
- a helical spring-type clutch 63 as shown in FIGS. 2 and 8, includes a helical body portion 63a constrictably secured about the periphery of starter shaft 15 and frictionally but yieldably engaged therewith.
- a free end 63b of clutch spring 63 is secured to the pin means 62 as shown generally in FIG. 8.
- Body portion 63a of the coil spring is arranged such that clockwise rotation of spring body portion 63a and arbor 58 about the stationary shaft 15 (viewing the apparatus as shown in FIG. 8) will induce automatic tightening or constriction of the coil spring clutch portion 63a about the shaft 15 and thereby transmit clockwise engine starting torque to the shaft 15.
- the automatic, overriding nature of the coil spring clutch portion 63a will ensure that transient clockwise rotation of the shaft 15 as shown in FIG. 8, which may occur at the outset of engine starting and which will occur when recoil starter means 23 is actuated, will not damage the oneway coil spring clutch mechanism 63a.
- This lever means 64 comprises a first lever 65 which is pivotally secured to wall 61 by a pivot mounting pin 66. As shown in FIG. 8, first lever 65 may pivot clockwise until its end 65a engages an abutment pin 67. Counterclockwise rotation of lever 65 in FIG. 8 is limited by engagement of lever end 65b with another abutment 68 carried by wall means 61.
- Biasing spring 69 biases a lever 65 to undergo counterclockwise movement, viewing the apparatus as shown in FIG. 8. This biasing is effected by securing one end 69a of the spring 69 against pin 68, while another extremity 69b. passing from a helical portion 69c secured to pin 66, engages a mounting aperture 650 of the lever 65.
- Spring means 69 thus will serve to bias lever 65 in a generally counterclockwise direction, as shown in FIG. 8, so as to cause the tipp 65a to be biased into the condition where it projects radially beyond the cylindrical periphery of wall means 61. This biasing will tend to dispose the lever extremity 65a at a position where it is abuttingly engageable with a second lever 70 now to be described.
- a second lever 70 included in lever means 64 is pivotally mounted on a pivot shaft 71, which shaft 71 is secured by the spider assembly 16.
- a biasing spring 72 serves to bias lever 70 so as to tend to cause this lever to undergo clockwise rotation about pin 71, viewing the apparatus as shown in FIG. 2.
- lever 70 causes lever end 70a to be biased into the path of the radially projecting extremity 65a of the first lever 65. If desired, the rest position of lever 70 may be determined by abutting engagement of lever 70a with the radial periphery of cylindrical wall means 61.
- lever 65 Because of the yieldably secured nature of the lever 65, rotational movement of the arbor 58 during restarting will not damage the lever 70 in the event that the lever end 70a should be disposed in the path of the projecting lever end 650. Centrifugal force acting on eccentrically weighted end 65b of lever 65 will cause lever 65 to pivot clockwise, as shown in FIG. 8, to move lever end 65a generally inwardly toward axis X and out of the path of lever 70.
- the stop button 11 may be arranged relative to lever 70 so as to prevent restarting initiating or depressing movement oflevcr end 70b when the button II is in an engine running position. It would only be when button 11 was slid longitudinally of housing 4 to an engine starting position, so as to move out of the abutting engagement relation shown in FIG. 2, that lever end 70b would be able to be depressed or moved counterclockwise about pivot pin 71 so as to effect starting operation of the energy storage means 53.
- energy storage means 53 functions and serves to selectively store restarting energy derived from generating means 43 and release this energy for transmission to starting shaft 15, it now becomes appropriate to consider a unique aspect of the invention which prevents overwinding or overstressing of spring 56 without involving any engagement or disengagement of components.
- This operation is achieved by energy diverting means 73 acting in cooperation with generating means 43.
- diverting means 73 comprises a reaction means 74 including an internal ring gear 75 and also includes slip clutch means 76.
- Reaction gear means 74 is coaxially arranged relative to spring case means 55 and its ring gear 75, like gear means 54, is diposed in meshing engagement with the planetary gears 51 and 53.
- a spring means may yieldably bias reaction means 74 to the left, as the apparatus is shown in FIG. 2.
- Ring gear portion 75 has a number of gear teeth somewhat different from the number of gear teeth on gear means 54. In one embodiment, for example, it is contemplated that gear means 75 may have 92 teeth, while gear means 54 have 90 teeth. This arrangement provides a reduction drive system somewhat similar to that described in the US. Pat. No. 3,453,906.
- reaction gear means 74 So long as reaction gear means 74 is stablized or immobilized relative to housing means 4, this reaction means 74 will function to transmit energy from shaft 15, through the gear means 46 and 47, to the winding gear means 54. This winding energy is then transmitted from gear means 54, through the spring case 55, to the restart spring 56.
- the slip clutch means 76 which serves to immobilize means 74 during winding of spring 56, may comprise a circumferentially constrictable metallic clutch band 77 disposed in circumferentially embracing engagement with the cylindrical periphery of gear means 74, is diposed in continuous, frictional but yieldable engagement with the cylindrical periphery of this reaction gear means 74.
- the generating means 43 including the planetary gear means 47, is disposed in continuous engagement with each of the energy storage means 53 and the reaction means 74.
- the band 77 of slip clutch means 76 will enable the reaction means 74 to rotate about axis X relative to housing means 4, and thereby dissipate energy and terminate the spring winding operation.
- the generator means 43 will again induce the rewinding of spring 56 for the purpose of effecting a subsequent restarting op eration. It is contemplated that such rewinding may be completed within a short time, possibly on the order of 15 seconds or so.
- the indicating means 25 may comprise an annular disc 78 interposed axially between the radially extending rims of gear means '75 and 54.
- disc means 78 may include one or more generally radially extending apertures 79 which house roller means 80 functioning as a friction clutch.
- Friction clutch roller means 80 is disposed in frictional but yieldable engagement with each of the rims of gear means 54 and 75. This engagement may be maintained by spring means, previously noted, urging reaction means 74 toward spring case 55.
- Disc 78 includes a longitudinally extending peripheral tab 81 which is located circumferentially between abutment means 82 and 83 carried by housing means 4. Housing means 4 may also include an indicating window means 84, the location of which is schematically shown by dotted lines in FIG. 9.
- reaction gear means 75 when reaction gear means 75 is held immobile by friction clutch 76, winding movement of the rim of gear means 54 will act on friction clutch means 70 so as to cause the disc 78 to move with the gear means 54 and position an indicia (or colored portion, green for example) 81a of tab means 81, refleeting a not wound condition of spring means 56, in alignment with indicator aperture 84.
- This alignment will occur as a result of the engagement of the lower end of tab 81, shown in FIG. 9, with the housingcarried stop 83.
- an operator may immediately determine the condition of spring means 56 by monitoring housing aperture 84 to determine whether or not sufficient energy has been accumulated in the restarter mechanism 24 for the restarting of a warm engine.
- FIG. 3 illustrates components of an energy level accumulation determining means 85 associated with the friction clutch means 76.
- Mechanism 85 includes a portion of housing means 4 which serves to secure one extremity 86 of the clutch band 77.
- the other end 87 of the clutch band 77 is disposed in selectively adjustable engagement with a plunger 88.
- Plunger 88 is yieldably and telescopingly supported in a housing recess by a coil spring 89.
- Coil spring 89 is supported by a threadably adjustable plug 90 mounted in this recess 9].
- Threaded manipulation of plug 90, relative to a housing recess 91, will serve to adjust the degree of circumferential contraction of the band 77 and thus selectively adjust the reaction force which must be exerted on reaction gear means 74 so as to permit movement thereof.
- the inclusion of spring 89 will ensure that the adjusting mechanism 26 will not be operated so as to permanently immobilize the gear means 74. In other words, the spring 89 will provide an upper limit for the level of reaction force which will permit movement of the gear means 74 and thus establish an upper limit on the level of winding of the spring 56.
- a principal advantage of the invention resides in the use of a restarting mechanism which enables restarting of a warm engine with minimal amounts of accumulated energy. This significantly reduces the weight and bulk of starting mechanisms. As a result, the ease and safety with which a chain saw, including this restarting mechanism, may be manipulated are significantly enhanced.
- Kopp specifically contemplates the utilization of disengaging and reengaging mechanisms.
- the indicating mechanism contributes to efficiency and reliability of the restarting operation in enabling an operator to determine, before attempting a restart, whether or not sufficient energy has been accumulated. ln knowing whether or not sufficient restarting energy has been accumulated, an operator can determine whether or not the restarter or recoil starter mechanism should be employed for engine starting purposes.
- the energy accumulation adjusting means enables an operator to make appropriate adjustments as may be necessary due to wear of friction clutch components, manufacturing variations, and changes in ambient temperature.
- a method of storing energy in an engine starting mechanism comprising:
- energy diverting means including energy transmitting reaction means engaged with said energy storage means and operable, while stationary relative to said energy storage means, to transmit energy from said generating means to said energy storage means, and slip clutch means yieldably and frictionally engaging said reaction means; after said amount of energy has been stored, diverting energy from said generating means through energy diverting means, away from said storage means while continuing to operate said engine and said generating means; initiating energy diverting operation of said energy diverting means in response to an accumulation of said amount of energy by said energy storage means, with said accumulation being operable to prevent said reaction means from transmitting energy from said generating means to said storage means by causing said reaction means to movably yield relative to said slip clutch means;
- a method of operating an engine starting mechanism comprising:
- said means for indicating including disc means intercalated between said reaction gear means and said ring gear means and being movable to a first position under the influence of said ring gear means when said energy storage means is received energy and to a second position under the influence of said reaction gear means when energy is being diverted to said energy diverting means; and
- a selectively adjustable clutch band operably engaged about the periphery of said reaction gear means.
- a starting apparatus for an internal combustion engine comprising:
- first ring gear means including a first number of gear teeth
- second ring gear means including a second number of gear teeth different from said first number
- drive gear means drivingly engaged with each of said first and second ring gear means and operable, in response to operation of said engine, to induce rotation of a movable one of said first and second ring gear means
- said first ring gear means being connected with said spring means and operable to impart spring stressing energy thereto
- releasable friction clutch means said second ring gear means being clutchingly engaged with said releasable friction clutch means, said second ring gear means being operable, when held stationary by said friction clutch means, to function as a force reacting means and cause said drive gear means to induce rotation of said first ring gear means
- said second ring gear means when permitted to undergo movement by said releasable friction clutch means, being operable to prevent said drive gear means from imparting rotational movement to said first ring gear means for the purpose of stressing said spring means;
- said releasable friction means being operable to permit rotation of said second ring gear means so as to cause said second ring means to prevent rotation of said first ring gear means in response to a degree of stressing of said spring means;
- release means selectively operable to release stress energy accumulated in said spring means and effect starting of said engine
- securing means selectively operable to secure said spring means during stressing thereof and prevent transmission of stress energy from said spring means to said engine.
- An apparatus as described in claim further including:
- energy level accumulation determining means operably associated with said clutch means and selectively operable to cause said clutch means to release said second ring gear means in response to different levels of energy accumulated in said spring means.
- a starting apparatus for an internal combustion engine comprising:
- first gear means including a first number of gear teeth
- second gear means including a second number of gear teeth different from said first number
- drive gear means drivingly engaged with each of said first and second gear means and operable, in response to operation of said engine, to induce rotation to a movable one of said first and second gear means
- said first gear means being connected with said spring means and operable to impart spring stressing energy thereto
- releasable friction clutch means said second gear means being clutchingly engaged with said releasable friction clutch means, said second gear means being operable, when held stationary by said friction clutch means, to function as a force reacting means and cause said drive gear means to induce rotation of said first gear means, and said second gear means, when permitted to undergo movement by said releasable friction clutch means, being operable to prevent said drive gear means from imparting rotational movement ot said first gear means for the purpose of stressing said spring means; said releasable friction means being operable to permit rotation of said second gear means so as to cause said
- first gear means including a first number of gear teeth
- second gear means including a second number of gear teeth different from said first number
- drive gear means drivingly engaged with each of said first and second gear means and operable, in response to operation of said engine, to induce rotation of a movable one of said first and second gear means; said first gear means being connected with said spring means and operable to impart spring stressing energy thereto; releasable friction clutch means; said second gear means being clutchingly engaged with said releasable friction clutch means, said second gear means being operable, when held stationary by said friction clutch means, to function as a force reacting means and cause said drive gear means to induce rotation of said first gear means, and said second gear means, when permitted to undergo movement by said releasable friction clutch means, being operable to prevent said drive gear means from imparting rotational movement to said drive gear means for the purpose of stressing said spring means;
- said releasable friction means being operable to permit rotation of said second gear means so as to cause said second gear means to prevent rotation of said first gear means in response to a degree of stressing of said spring means;
- release means selectively operable to release stress energy accumulated in said spring means and effect starting of said engine
- securing means selectively operable to secure said spring means during stressing thereof and prevent transmission of stress energy from said spring means to said engine
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Abstract
Description
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US364318A US3861374A (en) | 1971-05-05 | 1973-05-29 | Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14037171A | 1971-05-05 | 1971-05-05 | |
| US364318A US3861374A (en) | 1971-05-05 | 1973-05-29 | Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3861374A true US3861374A (en) | 1975-01-21 |
Family
ID=26838125
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US364318A Expired - Lifetime US3861374A (en) | 1971-05-05 | 1973-05-29 | Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3861374A (en) |
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4363298A (en) * | 1980-12-18 | 1982-12-14 | Outboard Marine Corporation | Lawn mower brake and starter |
| DE3432146A1 (en) * | 1983-09-06 | 1985-03-21 | Kioritz Corp., Mitaka, Tokio/Tokyo | COOLED BLOWER FOR INTERNAL COMBUSTION ENGINES WITH TOW ROPE STARTER |
| US5083534A (en) * | 1989-04-05 | 1992-01-28 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| EP0623743A1 (en) * | 1993-05-07 | 1994-11-09 | Nikkari Co., Ltd. | Power storage type recoil starter |
| US5572505A (en) * | 1994-07-21 | 1996-11-05 | Llewellyn; William D. | Spring starter for a hard disk drive platter assembly |
| US5738058A (en) * | 1993-11-24 | 1998-04-14 | Ray Gotto | Device for inhibiting the theft of pull-start internal combustion engines |
| US6311663B2 (en) * | 1998-10-30 | 2001-11-06 | Briggs & Stratton Corporation | Starting and stopping device for internal combustion engine |
| US6508220B1 (en) * | 1999-08-25 | 2003-01-21 | Kioritz Corporation | Starter |
| US6588390B2 (en) * | 2000-05-24 | 2003-07-08 | Kioritz Corporation | Recoil starter |
| US6595176B2 (en) * | 1998-10-30 | 2003-07-22 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6615787B2 (en) * | 1998-10-30 | 2003-09-09 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6647942B2 (en) * | 1998-10-30 | 2003-11-18 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6679217B2 (en) | 2001-03-01 | 2004-01-20 | Starting Industrial Co., Ltd. | Starter |
| US20040123828A1 (en) * | 2002-10-08 | 2004-07-01 | Mtd Products Inc, | Spring release starter for chain saw |
| US6901900B2 (en) | 2002-01-31 | 2005-06-07 | Kioritz Corporation | Recoil starter for backpack type power working machine |
| US20050252477A1 (en) * | 2004-05-14 | 2005-11-17 | Schriever Robert W | Energy storing starter assembly |
| US20060231055A1 (en) * | 2005-04-14 | 2006-10-19 | Goran Dahlberg | Energy storing starter assembly |
| EP1413746A3 (en) * | 2002-10-21 | 2007-03-14 | Starting Industrial Co., Ltd. | Recoil starter |
| FR2891592A1 (en) * | 2005-10-03 | 2007-04-06 | Peugeot Citroen Automobiles Sa | Heat engine starter for e.g. start-stop motor vehicle, has epicyclic gear coupled or decoupled by planet carrier connected to crankshaft, and blocking unit that maintains planet gear immobile in rotation and releases it for its rotation |
| US20080115756A1 (en) * | 2005-02-08 | 2008-05-22 | Zenoah Co. | Power Transmission Mechanism Between Engine Starting Device and Engine |
| US20090090094A1 (en) * | 2007-10-05 | 2009-04-09 | Black & Decker Inc. | Vegetation trimmer having a blowing function |
| EP1965073A4 (en) * | 2005-12-20 | 2012-04-25 | Husqvarna Zenoah Co Ltd | Engine start device |
| US20140165946A1 (en) * | 2012-12-14 | 2014-06-19 | Makita Corporation | Power tool |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1511082A (en) * | 1920-07-19 | 1924-10-07 | Johnston Floyd | Self-starter |
| US2857984A (en) * | 1957-03-18 | 1958-10-28 | James L Skinner | Engine starter |
| US2987057A (en) * | 1959-08-28 | 1961-06-06 | Alfred H Greening | Starter mechanism |
| US3032024A (en) * | 1960-08-09 | 1962-05-01 | Acme Die Casting Corp | Spring-impulse engine starter |
| US3149621A (en) * | 1960-10-14 | 1964-09-22 | Earl E Bailey | Turning device for rotatable shafts |
| US3583379A (en) * | 1968-04-30 | 1971-06-08 | Hatz Motoren | Starter device for an engine or the like |
-
1973
- 1973-05-29 US US364318A patent/US3861374A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1511082A (en) * | 1920-07-19 | 1924-10-07 | Johnston Floyd | Self-starter |
| US2857984A (en) * | 1957-03-18 | 1958-10-28 | James L Skinner | Engine starter |
| US2987057A (en) * | 1959-08-28 | 1961-06-06 | Alfred H Greening | Starter mechanism |
| US3032024A (en) * | 1960-08-09 | 1962-05-01 | Acme Die Casting Corp | Spring-impulse engine starter |
| US3149621A (en) * | 1960-10-14 | 1964-09-22 | Earl E Bailey | Turning device for rotatable shafts |
| US3583379A (en) * | 1968-04-30 | 1971-06-08 | Hatz Motoren | Starter device for an engine or the like |
Cited By (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4363298A (en) * | 1980-12-18 | 1982-12-14 | Outboard Marine Corporation | Lawn mower brake and starter |
| DE3432146A1 (en) * | 1983-09-06 | 1985-03-21 | Kioritz Corp., Mitaka, Tokio/Tokyo | COOLED BLOWER FOR INTERNAL COMBUSTION ENGINES WITH TOW ROPE STARTER |
| US4543915A (en) * | 1983-09-06 | 1985-10-01 | Kioritz Corporation | Cooling fan for recoil starter type engine |
| US5083534A (en) * | 1989-04-05 | 1992-01-28 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| US5113816A (en) * | 1989-04-05 | 1992-05-19 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| US5115773A (en) * | 1989-04-05 | 1992-05-26 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| US5163392A (en) * | 1989-04-05 | 1992-11-17 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| US5186134A (en) * | 1989-04-05 | 1993-02-16 | Mitsubishi Jukogyo Kabushiki Kaisha | Spiral spring type starter apparatus for an internal combustion engine |
| EP0623743A1 (en) * | 1993-05-07 | 1994-11-09 | Nikkari Co., Ltd. | Power storage type recoil starter |
| US5537966A (en) * | 1993-05-07 | 1996-07-23 | Nikkari Co., Ltd. | Power storage type recoil starter |
| US5738058A (en) * | 1993-11-24 | 1998-04-14 | Ray Gotto | Device for inhibiting the theft of pull-start internal combustion engines |
| US5572505A (en) * | 1994-07-21 | 1996-11-05 | Llewellyn; William D. | Spring starter for a hard disk drive platter assembly |
| US6311663B2 (en) * | 1998-10-30 | 2001-11-06 | Briggs & Stratton Corporation | Starting and stopping device for internal combustion engine |
| US6595176B2 (en) * | 1998-10-30 | 2003-07-22 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6615787B2 (en) * | 1998-10-30 | 2003-09-09 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6647942B2 (en) * | 1998-10-30 | 2003-11-18 | Briggs & Stratton Corporation | Engine starting and stopping device |
| US6508220B1 (en) * | 1999-08-25 | 2003-01-21 | Kioritz Corporation | Starter |
| US6588390B2 (en) * | 2000-05-24 | 2003-07-08 | Kioritz Corporation | Recoil starter |
| US6679217B2 (en) | 2001-03-01 | 2004-01-20 | Starting Industrial Co., Ltd. | Starter |
| US6901900B2 (en) | 2002-01-31 | 2005-06-07 | Kioritz Corporation | Recoil starter for backpack type power working machine |
| US6782863B2 (en) | 2002-10-08 | 2004-08-31 | Mtd Products Inc. | Spring release starter |
| US6834633B2 (en) | 2002-10-08 | 2004-12-28 | Mtd Products Inc | Spring release starter for chain saw |
| US20040123828A1 (en) * | 2002-10-08 | 2004-07-01 | Mtd Products Inc, | Spring release starter for chain saw |
| EP1413746A3 (en) * | 2002-10-21 | 2007-03-14 | Starting Industrial Co., Ltd. | Recoil starter |
| US7191752B2 (en) | 2004-05-14 | 2007-03-20 | Husqvarna Outdoor Products Inc. | Energy storing starter assembly |
| US20050252477A1 (en) * | 2004-05-14 | 2005-11-17 | Schriever Robert W | Energy storing starter assembly |
| US20080115756A1 (en) * | 2005-02-08 | 2008-05-22 | Zenoah Co. | Power Transmission Mechanism Between Engine Starting Device and Engine |
| US7819105B2 (en) * | 2005-02-08 | 2010-10-26 | Starting Industrial Co., Ltd. | Power transmission mechanism between engine starting device and engine |
| EP1865196A4 (en) * | 2005-02-08 | 2011-01-05 | Husqvarna Zenoah Co Ltd | POWER TRANSMISSION MECHANISM BETWEEN STARTER AND MOTOR |
| US7140341B2 (en) | 2005-04-14 | 2006-11-28 | Aktiebolaget Electrolux | Energy storing starter assembly |
| US20060231055A1 (en) * | 2005-04-14 | 2006-10-19 | Goran Dahlberg | Energy storing starter assembly |
| FR2891592A1 (en) * | 2005-10-03 | 2007-04-06 | Peugeot Citroen Automobiles Sa | Heat engine starter for e.g. start-stop motor vehicle, has epicyclic gear coupled or decoupled by planet carrier connected to crankshaft, and blocking unit that maintains planet gear immobile in rotation and releases it for its rotation |
| EP1965073A4 (en) * | 2005-12-20 | 2012-04-25 | Husqvarna Zenoah Co Ltd | Engine start device |
| US20090090094A1 (en) * | 2007-10-05 | 2009-04-09 | Black & Decker Inc. | Vegetation trimmer having a blowing function |
| US8256120B2 (en) * | 2007-10-05 | 2012-09-04 | Black & Decker Inc. | Vegetation trimmer having a blowing function |
| US20140165946A1 (en) * | 2012-12-14 | 2014-06-19 | Makita Corporation | Power tool |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1365144B1 (en) | Starting and stopping device for an engine | |
| US3306277A (en) | Spring starter for internal combustion engines | |
| US3763842A (en) | Lightweight chain saw with engine restarting system and method and apparatus for restarting a warm internal combustion engine | |
| US6622683B2 (en) | Engine starting and stopping device | |
| US2568136A (en) | Engine starter | |
| US2744586A (en) | Engine starter | |
| US2804173A (en) | Turning device for rotatable body | |
| US6595176B2 (en) | Engine starting and stopping device | |
| USRE20995E (en) | beasley | |
| US3139877A (en) | Mechanical starter motor energized by engine operation | |
| US2511908A (en) | Engine starter unit | |
| US4363298A (en) | Lawn mower brake and starter | |
| US3032024A (en) | Spring-impulse engine starter | |
| US2950780A (en) | Starting mechanism for an internal combustion engine | |
| US2999490A (en) | Spring starter | |
| US4426961A (en) | Starting arrangement for internal combustion engine | |
| US2163829A (en) | Engine starter | |
| US3205881A (en) | Dog mechanism for starter | |
| US3097634A (en) | Engine starter | |
| US1475815A (en) | Starter for explosive engines | |
| US2990827A (en) | Spring starter for internal combustion engines | |
| JPH0724614Y2 (en) | Internal combustion engine starter | |
| US1936555A (en) | Engine starting mechanism | |
| US1973288A (en) | Engine starting mechanism | |
| US2987058A (en) | Starter mechanism |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 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 |
|
| AS | Assignment |
Owner name: CITICORP INDUSTRIAL CREDIT, INC., 450 MAMARONECK A Free format text: MORTGAGE;ASSIGNORS:MC CULLOCH CORPORATION;MC CULLOCH OVERSEAS N.V.;REEL/FRAME:004158/0190 Effective date: 19830331 Owner name: CITICORP INDUSTRIAL CREDIT, INC., NEW YORK Free format text: MORTGAGE;ASSIGNORS:MC CULLOCH CORPORATION;MC CULLOCH OVERSEAS N.V.;REEL/FRAME:004158/0190 Effective date: 19830331 |
|
| AS | Assignment |
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 |