DE2211712A1 - Method and device for restarting a warm internal combustion engine in a light chain saw - Google Patents

Description

DIPL.-ING. KLAUS BEHN DIPL.-PHYS. ROBERT MUNZHUBER 2211712

PATENT LAWYERS

8 MUNICH 22 Wl DENMAYERSTRASSE β

TEL. (Ο811) 222530-295192

March 10, 1972 Our reference: A 5172/5272 - Pp / La

MeCULLOCH COEPORATiOtf, 6101 West Century Boulevard, Los Angeles4 California 9004-5, V. St. A.

Method and device for restarting a warm Internal combustion engine in a light chainsaw.

In recent years, there has been increasing consumer interest in the chain saw field the use of portable devices, mainly used by homeowners, and with an increased ease and effectiveness can be managed.

Among the most diverse points, two factors have particularly contributed to the economic success of the very light chainsaws contributed.

Modern technology and new techniques

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made possible the production of chainsaws in an extremely compact design, "with which motor and gear" systems simplified and reduced in weight.

Recently, "considerable efforts have been directed towards the establishment of a re-start mechanism, in which an electrical restart energy automatically in a starting mechanism during the Run of the chainsaw so that it was possible for an operator to restart the chainsaw effect.

Such electrical re-start mechanisms, despite certain advantages, have had an increase in weight and size of the portable chainsaws, so that there is a significant limitation of their Area of application where particularly light chainsaws would have been necessary.

Such particularly light chainsaws are increasingly required by the consumer, in particular from simpler homeowners.

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Thus, the invention is based on the idea of a repeat start mechanism for the effective Use on a "particularly light chainsaw, without the size or weight of such a chainsaw "increasing noticeably. There" the invention is directed also on a control mechanism for the repeat start, which prevents over-tensioning of a spring for restarting the engine and the necessity the disengagement of the motor from the winding means the repeat start spring after the winding process makes redundant.

The result of the invention is an improvement and expansion of the usability of portable chainsaws, as well as an increase in operator safety.

All of this is achieved without a costly redesign of the engine and / or the transmission parts, as well of the cutting chain mechanism built into the light and portable chainsaw.

It is therefore the main object of the invention to provide a very lightweight chainsaw with a repeat start

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Provide mechanism that has a low weight, no increase in mass or circumference and yet is extremely reliable in operation. That arranges a task the goal is a starting system for an internal combustion engine to create, particularly of the type used in portable chainsaws, a recoil starter used to cause a cold chainsaw motor to start and a weaker repeat start mechanism is used to start a warm chainsaw motor. A procedure should be used and a device for restarting the Combustion engine of the type mostly used in chainsaws are provided, with the one necessary for starting the engine and the amount of energy stored is as low as possible. This method and device is intended to achieve that a coupling and uncoupling of elements in the winding system of the starting spring to avoid over-tensioning this spring becomes superfluous. In this context, the device should be equipped to the effect that there is one Operator is enabled, by certain means, the amount of the start system to restart the engine optionally to set stored energy. Furthermore, the operator should be able to determine whether the

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starting the engine stored energy is sufficient.

The object is achieved by a method for restarting an internal combustion engine, which in particular is of a type used in chainsaws.

In the practice of this method, the internal combustion engine is started while it is still cold and is below normal operating temperature. An amount of energy is then stored that is sufficient for is a restart of the engine. This amount of energy is sufficient to restart the engine when it is warm and at normal operating temperature. However, this amount of energy is relatively small and generally not sufficient to start the engine when it is cold and has a temperature that is significantly below the normal working temperature.

This reduced amount of stored energy is later used to restart the engine when it is warm and has a normal working temperature.

Another independent, significant process feature of the invention lies in the technology for re-

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recovery start of an engine, as it is especially with chainsaws is used.

This further feature of the invention is shown in producer means that are continuously "operational, in order to mechanically establish the means of restarting the engine. The BBUgte generated by these producer funds Energy is stored in an energy store until enough energy has accumulated that is sufficient for the To start the engine when it is warm and has a normal operating temperature, which, however, is not sufficient Start the engine when it is cold.

After this amount of energy in the energy store is stored, an additional one of the generating means (i.e. the mechanical means for generating the Repeat start energy for the motor) outgoing energy diverted from the memory by an energy distributor, while the producer funds continue to work. This! Activity of the energy distributor is dependent on a Sliding ability of counteracting means of energy transfer caused, which is made possible, for example, by a slip clutch.

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This slip clutch is constantly in one though frictional, yes, yielding intervention with the counteracting means held. In addition, the energy generating means are constantly engaged with each of the energy storage means and the counteraction means held so that an automatic diversion of the energy from the storage is achieved via the counteracting means and the slip clutch without engaging or disengaging the moving Parts is necessary.

A third independently noteworthy feature of the invention, particularly in the context of portable ones Chainsaws, can be seen in the display and voting system, since it relates to the energy storage.

With this third feature of the invention, means is provided which indicates that the memory is for a Repeat start of a warning motor from the detection means has not yet received a sufficient amount of energy. Another display informs the operator that the memory has received sufficient energy to start the engine.

In this third feature of the invention, a

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Slipping clutch kept operationally to a To give operator the opportunity to choose the amount of the collected or stored in the system Set the repeat start energy.

Other "features of the invention" relate to various Combinations of fixture elements that are used to carry out the above procedures in a unique way Cooperate in a way. These device elements are assembled in such a way that they can be used in their entirety Induce improvements in the operational characteristics of starter systems, particularly starter systems with chainsaws. These improvements go beyond the assigned effects of the individual elements out and show themselves in their interaction, with which starter systems and chainsaws are created, the one have significant weight reduction and improved repeat start characteristics. So are unusually light, safe, and easily restarted devices were created.

A very important device feature of the invention relates to a combination of a first and one second gear element, the one gear element

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is coupled to the coil assembly of a repeat start spring and the other gear element to an energy distribution mechanism connected is. A slip clutch associated with the latter gear element automatically deflects energy from the repeat start spring to an energy diverting mechanism without any coupling or decoupling activity of the drive parts necessary is.

In describing the invention, reference will be made to taken a preferred embodiment. However, it should be noted that this embodiment is only exemplary and not to serve as a limitation of the inventive concept.

The drawing shows an embodiment of the invention for example, show:

Fig. 1 is a partial perspective view of a light chain saw, in which the starting concept the present invention is embodied;

Fig. 2 is a partial cross-section through the recoil start mechanism and the repeat start mechanism from the chain saw according to FIG. 1, along section 2-2 in FIG. 1;

3 shows a cross-sectional representation in an enlarged

sertem scale of the section 3-3 from Fig. 2 with an elevation of a slip clutch mechanism, which has a divisible energy deflection function provides j

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Fig. 4- is a cross-section on an enlarged scale of section 4-4 from FIG a centrifugal force dependent clutch between the starter shaft and chain saw motor flywheel assembly;

i "ig. 5 a cross section 5-5 from FIG. 2 with a ratchet-like recoil mechanism of the starter part shown in FIG. 2;

Fig. 6 is an elevation of the spoked wheel shown in Fig. 2, which forms part of the start and Repeat start shaft carries and also a rotatable support for a lever device provides for the initiation of the repeat start;

Fig. 7 is a partial elevational and cross-sectional view along the section 7-7 of FIG. 2 of the method of the rotatable mounting of a control or actuating lever for the repeat start;

FIG. 8 shows a cross section along section 8-8 from FIG. 2, with component and action relationships between the actuation lever of Fig. 7i release lever of the repeat start spring and clutch mechanism for torque transmission are shown; and

9 shows a partial view of the top view in the direction 9-9 from FIG. 2 with the display device for visual recognition of the amount of energy collected in the repeat start mechanism.

In describing a preferred embodiment, reference is made to a very advantageous and significant application the repeat starter according to the invention in one warm engine taken. This application means that a return

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recovery start mechanism for warm engines in a very light chainsaw is built in, which weighs 5 "Can have up to 6 pounds or less.

The main components of the chainsaw with the invention Principle of the Wi ederho treatment starts are shown in FIG.

Like the Pig. 1 shows, the chainsaw 1, in which the subject of the invention is arranged, a chain guide 2, which carries an articulated cutting chain 3.

The chain guide 2 stands from a housing 4 at ». This housing 4- "contains an internal combustion engine inside, usually a small two-stroke engine. A suitable one Drive system inside the housing 4- connects this motor with the cutting chain 3, possibly in terms of drive by means of a flywheel clutch as a torque transmission mechanism.

The housing 4- also contains a fuel tank 5, a carburetor system, and possibly others Auxiliary devices on the chainsaw, such as an oiling device or the like.

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The chainsaw 1 is made of a handle arrangement 6 worn, which consists of a longitudinal part 7 and a stabilizing transverse part 8 consists.

A throttle trigger 9 can be rotatably attached to the handle part 7. This throttle trigger serves the operator to give the opportunity to control the running speed of the chainsaw with the hand encompassing the handle part 7 to control.

The saw 1 also includes a starter and a repeat start assembly 10 and a control switch 11. -s

The starter assembly 10 has independently operating ji Components that are designed to cause a cold start and a warm start of the engine.

The switch 11 can be moved in the longitudinal direction of the housing and is intended to stop the engine from running in one position of the ignition circuit of the engine. The switch 11 can be operated either by hand on the handle 7 or on the handle part 8 operated by the operator.

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After the main components of the chainsaw 1 have been explained, the consideration should now be on the Core of the invention are directed, namely on the start and repeat start mechanism

Essential components of the starter arrangement 10 are shown in FIGS. 1, 2 and 3.

These main components have a flywheel 12 for the chain saw. The flywheel 12, as shown in FIG. 2, is mounted on a motor drive shaft 13. As FIG. 4 shows, the flywheel 12 can also have a number of 3 wing blades 14 · for cooling the motor.

A start and restart shaft 15 for the engine is mounted in the housing 4 and can be supported by a spoked wheel 16 and a roller bearing-Anrg. extension 17 can be rotated.

The structure of the starter shaft 15 is known and she owns, like the prop. 2 and 4- show a cylindrical End piece'B, which is a series of circularly arranged and has longitudinally extending slots 19.

On the flywheel 12 there can be a plurality - there are two of them

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shown - be provided by drivers or latches 20. Each of these drivers or pawls 20 is rotatable supported on the flywheel 12 by means of a pivot 21. A common coil spring 22 is with both the pivot 21 as connected to the hole of the pawl 20 and forces the one eccentrically protruding end 20a each Latch, extends generally radially inward to the central axis of rotation X of the starting assembly and the motor shaft 13 to be addressed.

As shown in Figs. 2 and 4, each spring 22 has a coil spring thread portion 22a which corresponds to the associated one Pivot 21 surrounds. One end 22b of each spring rests against an abutment part of the flywheel 12. The other end part 22c is held in an opening 20d of the latching pawl and serves to hold the pawl end 20e in Direction to force the X-axis.

Each pawl can have an end 20b which rests against a fan blade 14 in a force-locking manner in order to thereby the Movement inward of the pawl end 20e in that shown in Fig. 4- End position.

With this arrangement, the pawl protrusions,

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d. H. the stop parts 20c in stop engagement with the edges 19a of the slots 19, as shown in Fig. 4-.

When the pawls 20 as shown in Fig. A- in relation are arranged to the starter shaft 15, then a start or restart torque generated by the starter assembly 10 transferred to the motor from shaft 15, namely through the pawls 20 on the flywheel 12 and then ■ from the flywheel 12 on the motor shaft 1 $, which starts of the motor is effected.

Once the engine has started, the flywheel 12 reaches a sufficient running speed so that the unbalanced pawl ends 20a are forced to move radially outward due to a centrifugal force "move wcamit an automatic unlocking of the current Motor from the start and restart shaft 15 takes place.

At this point it should be noted that the engine starting torque counterclockwise (when viewing 2 from the right) of the shaft 15 can be imparted by one of the two starting mechanisms which are present in the starting arrangement 10.

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The first of these two starting mechanisms, used when starting the chainsaw when the engine is running is cold has a known recoil starter assembly 23.

Once the engine has reached normal working temperature and is stopped temporarily, Äaö When a chainsaw is used, a recovery start can be initiated by a restart mechanism will.

In this context it is important to note that the term "normal working temperature" has to be understood in a broad sense _. around a wide temperature range of a chainsaw motor to μΐηΐΒβββη, which one encounters with the length of time in which a chainsaw is in operation. As used herein, the term "normal working temperature" includes working temperatures at which the machine is running and somewhat reduced temperatures which arise when the chainsaw is interrupted for a short period of time during normal sawing operations. Such interruptions take place, for example, when the operator has to change his position or the position of the saw.

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The function of the recoil start mechanism 2 $ is used to put the chainsaw motor into operation, when an operator first starts using the saw and the engine is still cold, d. H. on a Is the ambient temperature, which is substantially below the normal working temperature. After the saw. Once has been started, the operator can achieve a repeat start by stopping the cutting The process has briefly interrupted that it actuates the restart mechanism 24.

A display device shown generally in FIGS. 2 and 9 25 enables the operator to determine whether the restart mechanism 24 is operational is.

Depending on the working conditions, such as partial wear, ambient temperatures etc., it can be used for an operator can be attached to the stored energy strength by the restart mechanism 24 to The purpose of restarting the motor. These The stored energy level to be used for restarting the motor can be set by manipulation of the operator can be effected,

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which they use the Speiclierbegrenzuiigs-Elemeiite 26 for the energy strength which are shown generally in FIG.

Now that the main components of the start and restart system have been described, it is appropriate to the consideration of details of the start arrangement 23) the restart arrangement 24, the display arrangement 25 and to direct the energy storage limiting elements 26.

Details of the starter assembly 23 are shown in FIGS Figs. 1, 2, 4 and 5 are shown.

The recoil starter arrangement 23 has a disk-like wheel 27 which is mounted on the starter shaft 15 is.

The disk 27 is secured to the shaft 15 by a snap ring 28 engaging at the left end of the disk held in a certain position, as shown in FIG. The right end of the disc 27 can by a annular housing wall 29 which encircles the shaft 15 and is secured by a cylindrical housing part 30 the spoke arrangement 16 is held immovable.

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A common spiral wound Recoil spring 31 is radial between shaft 15 and cylindrical Housing wall 30 attached. Bas an end 31a of the spring 31 is attached to the housing wall 30 ", whereas the other end 31b at the generally cylindrical one ! Hub part 27a of the disk 27 is attached.

At this point it is useful to look at the figure. The spoke mechanism 16 has a Honeycomb 16a, in which the wave 1 !? is stored. A row arms 16b extend generally radially from the honeycomb 16a in an inclined l'orm outwards, as in l'ig. 2 can be seen, so that a holder is provided for the cylindrical wall 30.

In the radial parts of the retaining tabs 16c ■ of the spoke wheel 16, drill holes or eyelets 16d are provided, which receive the retaining pins 16e, of which 'one is shown schematically in the I'ig. 2 is shown. tuck Retaining pins are threadedly attached to protruding parts in the interior of the housing 4 such that the Spoked wheel arrangement 16 is firmly anchored to the housing 4.

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As in i'ig. 6, one of the radially extending retaining tabs 16c has a direction towards this approximately transverse opening 16f. This opening receives a pivot pin 71 which is connected to an operating lever 70 is connected. This will be described in more detail later.

The disc 27 also has a radially extending and outwardly open recess 32 which receives a conventional, spirally wound pull cord 33. The pull line 33 has a customary pull handle 13 ² S at its outer end, as shown in FIG. 1.

As FIG. 5 shows, this can be done through an opening 27a in the disc leading out inner end 33a of the pull cord 33 can be secured by a knot in this end.

The pull line 33 is in this way on the disc 27 wound that a pull on the handle 134-, in which one Rotation of disk 27 counterclockwise (when viewing the device from the right side according to Fig. 2) and a unwinding of the pull line is caused at the same time Tensioning or a spiral winding of the spring 31 causes, so that a restoring force for the pulley and a rewinding force for the pull line are generated.

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2 and 5 it can be seen that a plurality of locking levers or pawls 34 (are shown two) can be rotatably supported by pivot pins 35 and extend from the left end of the disc 27, as shown in FIG. shows.

The outer ends 34a of the pawls 34 are by the spring assemblies 36 substantially radially held inside, as shown in FIGS. 2 and 5.

Each such spring arrangement consists of a leg portion 36a with a bent end 36b which is shown in FIG an opening 34b of the pawl 34 engages. A coiled coiled portion 36c of each spring 36 is on the pivot pin 35 attached, while the other leg portion 36d of each spring rests against a stop pin 37 or in another is appropriately engaged with this pin. The tension of each spring 36 is such that whose leg parts 36d and 36a tend to come apart and that the associated pawl end 34-a from the assigned and firmly attached to the disk 27 Stop pin 37 is moved away.

This spring mechanism with the corresponding

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Pawl 34- causes a pawl stop part 34-c into one Ratchet engagement with a ratchet part 15a of the while 15 to come. This part of the ratchet wheel consists of a none separately arranged openings 38 in the circumference Starter shaft as shown generally in FIG.

The stop parts 34-c of the pawls 34- are "at a Rotation in the clockwise direction of the disk 27 relative to the shaft 15 as shown in FIG. 5 is able ("when viewed from the side from the right in Fig. 2 counterclockwise), with the stop edges 39 of the sides of the shaft slots 38 to come into engagement and thereby cause a clockwise movement of the starter shaft 15. Such a move the disc 2 '/ and the starter shaft 15 clockwise, As shown in FIG. 5, pulling the handle 134 · is used to start the engine.

! After the pull line 33 has been pulled out, the tension of the spring 31 automatically causes the retraction or rewinding the line 33? being the hatch effect between pawls 34 and slots 38 due to the general design of these components shown in FIG. 5, a ratchet rewinding operation is possible.

During the after pulling the handle 134-

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the pawls 20 on the flywheel are in a drive position brought with the shaft end such that an engine start with respect to the rotation of the disc 27 is enabled. is however the start of the engine, once done, is done through the outward centrifugal movement of the pawls 20 the motor is disengaged from the starter shaft 15, so that the shaft 15 stops during normal Mbtorlaufes.

The possibility -that the shaft 15 is clockwise an "advice" movement (shown in Figure 5) relative to the disc pawls 34- performs, ensures that no Motor that causes shaft 15 to rotate, the mechanism 23 can damage.

The structure described so far and the corresponding Operation relate to the case in which an operator has a cold chainsaw " Want to start the engine.

Let us now consider the structure and the technology for a repeat start of a warm Chainsaw motor can be turned on. Such a restart could be periodic during normal operation a chainsaw occur when it becomes necessary for the operator to stop the sawing process momentarily or temporarily

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to interrupt. Such interruptions can, for example occur when it is necessary for the operator for safety reasons, a new cutting position to take, or for other reasons.

Details of the construction and operation of the retry start mechanism 24- are on the basis of the individual, in Figs. 2, 5, 7 u ^ -d β shown components of this Mechanism described.

In describing the repeat start mechanism and how it works, this should be clarified It will be noted that the significant features of the invention emerge particularly in the following two points:

1. The principle of a starting system of a chainsaw in which only a limited amount of energy is required is and must be stored for the purpose of restart, this amount of energy for the restart a warm engine is sufficient, but not for starting a cold engine; and

2. a system that avoids overspeeding and that is linked to a repeat start

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which is characterized by the fact that a continuous Coupling prevails between the components in such a way that "latching and releasing protiles are avoided".

Following these general criteria, let us now look at the details of the restart mechanism 24 should be considered in more detail.

The Repeat Start Mechanism '24, hereinafter also called restart mechanism 24 for short, "has an i'ederwickel shaft 40, shown" for example in FIG i'ig. 2.

Me wave 40 wears, as in i'ig. 2 can be seen at its left end a socket 41 with a polygonal cross-section. The socket 41 engages for torque transmission with matching roofs on a polygon nut 42, which is fastened with its thread on a threaded end 13a of the motor shaft 13.

The nut 42 is used to hold the flywheel 12 on the shaft 13.

With this arrangement, the shaft 40 ″ serves the

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Running of the motor of the chainsaw and while rotating the shaft 13 as part of continuously operating generating means 43 for generating restart energy.

Before the additional details of the producer funds 43 is followed, it seems useful here to note that the shaft 40 through at its left end the nut 42 and is supported at its far right end by a roller bearing assembly 44. The roller bearing arrangement 44 is in turn held in a bore 45 of the housing 4.

The generating means 43 consist, in addition to the shaft 40, of a pinion or drive gear 46 and from an epicyclic gear arrangement 47.

As shown in FIGS. 2 and 3, the pinion 46 is fixed to the shaft by a cross pin 48 tied together.

The epicyclic gear assembly 47 has a radially extending arm or body 49 which is in a Chamber is mounted that the roller bearing assembly 50 for carries a rotation about the X-axis.

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The arm 49 carries epicyclic gears 51 and 52 rotatably mounted at its radial ends. Each of the epicyclic gears 51 and 52 is in drive engagement with
the Bitζel 46.

Each of the gear parts 51 and 52 of the epicyclic gear arrangement 47 is in a continuously interlocking arrangement with energy storage elements 53. These energy storage elements 53 consist of a radial
inward ring gear 54? which is in interlocking contact with the epicyclic gears 51 and 52.

The ring gear 5 ^ is of a general cylindrical housing 55 carried by a restart spring, which is mounted on the outside of the shaft 15.

A helically wound restart spring 56 is radially between a cylindrical end 57 of the housing 55 and the shaft 15 are used.

The outer end of the spring 56 is on the rotatable Spring housing part 57 attached. The radially inner end of the Spring 56 is attached to a spring shaft 58. The spring axis

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58 thus lies radially between spring 56 and shaft 15

As shown in Fig. 2, the axis 5 & have a cylindrical portion 59 resting on a cylindrical body or base 60 of the housing 55 and to which the inner end of the spring 56 "is attached is.

The axis 58 can also be a general one have radially extending wall 61, which serves to limit the left side of the spring 56, the the right side of the spring 56 is limited by the spring housing 55 will.

It can now be assumed that after the axle 58 and its wall 61 are held in place relative to the housing 4 rotation of the spring housing 55 will bring about tension or winding of the spring 56.

Conversely, after the spring 56 is tensioned or has been wound up and the housing 55 is held in place with the axis 58 and its wall 61 free for a rotation about the shaft 15 achieved that the spring energy from the axis 58 to the shaft 15 for the purpose of

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Restarting the engine is transmitted.

This mode of operation of the spring housing 55 and the Axis 58 will now be considered in more detail.

The wall .61 on the axis has retaining pin elements 62 for a leather. A spiral-shaped, feather-like one Coupling 63, as shown in FIGS. 2 and 8, has a spiral-shaped part 63a, which is drawn tightly around the The circumference of the starter shaft 15 is and with this, although with friction, it is resiliently connected.

A free end 63b of the clutch spring 63 is attached to the pin members 62 as generally is shown in FIG.

The body part 63a of the coil spring is arranged such that rotation of the spring body part 63a and of the axis 58 clockwise around the fixed shaft 15 (at 8) a reclamping or contraction of the coupling part 63a of the coil spring around the shaft 15 is automatically effected and thereby transmits a clockwise engine starting torque to the shaft 15. The automatic coupling part 63a of the

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Coil spring with its controllability ensures that a temporary clockwise rotation of shaft 15 (as shown in Fig. 8) which occurs at the start of engine start can and then occurs when the recoil start mit-. tel 23 are in operation, the one-way clutch mechanism 63a will not damage the coil spring.

The optional fixing of the axis 58 or the Leaving this axis free for a rotary movement relative to the Shaft 15 for transferring the stored spring energy this is controlled by the lever assembly 64.

This lever arrangement 6A- has a first one Lever 65 which is rotatably attached to the wall 61 by means of a pivot pin 66. As FIG. 8 shows, can the first lever 65 can be rotated clockwise until its end 65a hits a stop pin 67. One twist counterclockwise of the lever 65 in FIG. 8 is caused by the lever end 65b striking another stop 68 on the wall 61 limited.

A tension spring partially wrapped around pin 66 69 forces the lever 65 to move counterclockwise when the device, as shown in Fig. 8,

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"is considered. This compulsion is achieved by one end 69a of the spring 69 is attached to the pin 68, while the other end 69b, which extends from the spiral-shaped part 69c placed around the pin 66, into a holding opening 65c of the lever 65 engages.

The spring arrangement 69 thus serves to hold the lever 65 in a counterclockwise direction, 8 shows, so that the extreme end 65a is brought into a position in which it radjal by means of tension protrudes beyond the cylindrical circumference of the wall 61. This tension is aimed at the "lever end 65a in a To hold position in which it can abut with a second lever 70, which is described below will.

The second lever 70 of the lever assembly 64 is rotatably mounted on a pivot pin 71 which is attached to the Storage wheel assembly 16 is attached. As shown generally in Figures 2 and 7, a tension spring 72 acts in such a manner on lever 70 to cause it to rotate clockwise around the pin 71 is forced when using the device viewed as shown in FIG.

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The tension of the lever 70 leaves the lever end 70a in the way of the radially protruding end 65a of the first lever 65. If desired, the end position of the lever 70 can be achieved by striking the end of the lever 70a can be determined on the radial circumference of the cylinder wall 61.

When the coiling of the spring 4-6 is started and when the lever 70 in that shown in FIG Position is in which its end 70a is in the circular path of the lever end 65a, so that the winding of the spring 56 cause the axis 58 to be the lever end 65a comes into abutment with the lever end 70a. When this stop is done, there is another rotation or movement of the axis 58 is prevented. Thus, as the housing 55 continues to rotate, it is held in place Axis 58 a winding or tensioning of the helically wound coil spring 56 is achieved.

Because of the resilient mounting of the lever 65, a rotational movement of the axis 58 during the repeat start Do not damage the lever 70 if its end 70a gets in the way of the protruding lever end 65a should be brought. A centrifugal force acts on it

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the eccentrically mounted lever 65 and the overweight lever end 65b and thus causes the lever 65 to one Clockwise rotation, as shown in Figure 8, bringing the lever end 65a substantially inward on the X-axis and is moved out of the way of Lever '70.

After the spring 56 is wound, a Operator depress a lever end 70b projecting beyond the housing, so that the lever end '70a from the Stop contact with the lever 65 is moved away. This enables the axis 58 itself and the shaft 15 (when viewed of the device from the right-hand side of FIG. 2) in a counterclockwise direction, whereby the frictional interaction between the spiral Clutch spring member 63a and shaft 15 contract of the spring part 63a, so that the spring 56 for torque transmission with the shaft 15 in an intermediate clutch engagement stands.

The stop button 11 can be arranged in relation to the lever in such a way that triggering the repeat start or depressing the end of the lever 70b is avoided when the button 11 assumes a certain position while the engine is running. Only when the button 11 is along the

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Housing is moved to an engine starting position, so that it moves out of the stop relationship shown in FIG is, "the lever end 70b has the option of being depressed or counterclockwise about the pivot pin 71 to be rotated so that a start operation of the energy storage means 53 is achieved.

After the mode of operation of the energy storage means 53 "has been described, how this optionally the Restart energy arriving from the generating means 4-3 save it and release it again at the start of shaft 15.

/ can
It now appears expedient to consider the particular feature of the invention by which over-tightening or over-tensioning of the spring 56 is avoided without the need to engage or disengage components.

This process is carried out by the energy distribution means who cooperate with the producer means 43.

As shown essentially in FIG. 2, the distribution means 73 consist of counteracting means 74 with an inner ring gear 75 and also from one Slip clutch 76.

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The counteracting means 74 are relative to the spring housing 55 arranged coaxially and its ring gear 75 is just like the gear 54 with the planetary gears 51 and 52 interdigitated. One not shown The spring device can then push the counteracting means 7 ^ to the left as shown in FIG.

The ring gear 75 "has a number of teeth which differs slightly from the number of teeth on gear 54. For example, in one embodiment it has been contemplated that gear 75 may have 92 teeth, as opposed to it the gear 54 may have 90 teeth. This arrangement provides a reduction system similar to that disclosed in US Pat 3 453 906 described device Has similarities. · ■

How this step-down drive assembly works is such that in a fixed position of the counteracting means 74 relative to the housing 4, the interlocking the planetary gears 51 and 52 in the ring gears 54 and 75 causes the spring housing 55 to be wound up relatively slowly. As long as the counteraction gear 74 is fixed or held in place relative to the housing 4, this counteracting gear 74 causes energy from

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of the shaft 15 via the transmission means 46 and 47 to the Winding gear 5 ^ - is transferred. This winding energy is then from gear 54 over the spring housing 55 transferred to the restart spring 56.

The slip clutch 76, which is used to hold the means 74 during the winding of the spring 56, can be off a circular, contractible, metallic coupling band 77 exist, which surrounds the cylindrical outer circumference of the Zabnradanordnung 74 and that with this cylindrical circumference of the counteracting means 74- in a continuous, frictional, but yielding engagement. The producer funds are similar 43, including the epicyclic gear 47, in continuous engagement with both the energy storage means 53 and counteracting means 74.

Once a certain amount of energy has been transferred to the spring 56, which is sufficient for a repeat start a warm, a normal working temperature having motor is, however, not sufficient for overstressing the spring 56 or for starting a cold Motor is, the belt 77 can cLer slip clutch 76 the rotation of the counteracting means 74 about the X-axis is relative

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to the housing 4, whereby the energy is lost and the spring winding process has ended.

This process is carried out by a selected setting of the slip clutch 76 »so that it has the counteractive means 74- holds "until a counteraction from Housing 55 and the gear 54 backwards via the planetary gears 51 and- 52 is transferred to the gear 74-, its counteraction of the amount of energy collected in the spring 56 which is sufficient to cause a restart of the warm engine. Is this counteraction process once this has occurred, the slip clutch 76 enables the counteracting means 74 to slide or rotate. As a result, the housing 55 stops, so that the winding process of the spring 56 is ended and the continuous The activity of the orbital gears only produces one more rotation the counteracting means 74 - relative to the slip clutch 76. Overstretching of the spring 56 is thus avoided.

It is noteworthy that this prevents tensioning achieved without any special coupling or uncoupling process of components of the restarter 24 will.

The restart of the warm engine of the chain

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saw 1 is briefly interrupted after the cutting process has been effected according to the following sequence ":

1. Lay out during initial engine run the generating means 43 for mechanical energy (consisting of shaft 40, pinion 46 and epicyclic gear 47) the spring housing 55 a spring winding movement. The lever assemblies 65 and 70 stop during this winding process the restarter spring axis 58 relative to the starter shaft 15 fixed.

2. If sufficient to restart a warm engine, but sufficient to restart a cold engine insufficient amount of energy stored in the spring 56 has been, there is a counteraction from the gear 54 via the epicyclic gear 47 to the counteraction gear 75 transferred. This counteraction produces a sliding of the counteraction means 74 relative to the slip clutch 76. As The result of this sliding between the slip clutch 76 and the counteracting means 74, the spring coil housing 55 is stopped, so that the winding operation of the spring 56 is ended is.

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3. After the winding process of the spring 56 "has been completed, the generating means 4-3 continue in their activity and remain in engagement with the winding housing 55 and also with the energy distribution means 73 (consisting of counteracting means 74-" and slip- '; coupling 76). At this point, however, the energy is diverted or wasted by sliding or rotating the counteracting means 74 relative to the slip clutch 76.

4. When the engine is to be restarted, the operator depresses the lever end 70b, whereby the axis 58 is released for rotation. The rotation the axis 58 causes the spiral spring clutch the shaft 15 engages around the coupling and the restart torque from the spring 56 to the latches 20 of the flywheel 12 transmits. The so transferred to these jacks Torque is transmitted through the pins 21 and the flywheel to the motor shaft 13, thus starting the motor is effected. Once the motor has started, the locking pawls are released due to the centrifugal force of the flywheel from the shaft 15

5 Once the motor has restarted, the generating means 4-3 call for the spring 56 to be wound up again for one

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nen subsequent, new restart process. The aim was that such a rewinding can be completed in a short time, about 15 seconds.

Having described the overall structure and operation of the restart mechanism 24, it now appears expedient, the structural details of the display arrangement 25 and the limiting means 26 for to take a closer look at the accumulated energy level.

The display means 25 can have an annular disc 78 axially between the radially extending edges of the gears 75 and 54 is set.

As seen in Fig. 9, the disc 78 can be one or more substantially radially extending Have openings 79 with housing rollers 80, which act as a friction clutch. The friction clutch rollers 80 are in a frictional, yet yielding connection with each of the edges of the gears 54 and 75 · These The connection can be maintained by spring elements, as mentioned above, which the counteracting means 74 press the spring housing 55.

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The disc 78 has a on the outer periphery longitudinally extending tab 81 which lies between two stops 82 and 8 3 attached to the housing 4. The housing 4 can also have a display window 84, the position of which is shown schematically with dashed lines is shown in FIG.

If the counteracting gear 75 is held immovable by the slip clutch 76, with this arrangement the winding movement of the edge of the gear 54 on the friction clutch 79 act so that the disc

78 moved with the gear 54 and into a display position 81a of the tab 81 (also color coding, for example green) is brought, the condition of the spring 56 "not tensioned" is displayed in alignment with the display aperture 84. This alignment takes place on the stop of the upper end of the tab 81 to the housing stop 82, .As FIG. 9 shows.

When the winding is finished, so that the housing 55 and. cLas gear 54 is held and the counteracting gear begins to rotate, the friction clutch operates

79 j that the disc 78 moves with the gear 75 and the tab 81 is brought into the position shown in FIG.

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In this position, a part of the advertisement (or a colored part, e.g. red) 81a of the tab. 81 the condition of the spring 56 "cocked" again that is in alignment with the window 84 lies. This alignment is maintained by that the lower end of the tab .81b in Fig. 9 with the housing stop 83 comes into contact.

It should be noted at this point that the
Reduction arrangement from the gears 54 and 75 is such that these gears are moved relative to the X-axis and to the housing 4 in mutually opposite directions when they move themselves.

Thus, an operator can immediately
determine the condition of the spring 56 through the indicator port 84 in the housing and determine whether there is sufficient stored energy in the restart mechanism 24 to restart the warm engine.

In Fig. 3 are in connection with the friction clutch 76 Limiting elements 85 for the energy level shown.

The elements 85 close part of the

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housing 4- with a, which serves to one end 86 of the coupling band 77 to hold. The other end 87 of the coupling band 77 is arranged in an optionally adjustable connection with a tuning bolt 88. The voting bola 88 is held resiliently and telescopically sprung in a receptacle in the housing by a coil spring 89. The coil spring 89 in turn is guided by a screw pin 90 held in this receptacle 91, which is adjustable by means of a thread.

The thread setting of the screw pin 90 relative to the housing receptacle 91 is used to measure the degree to adjust the circular contraction of the band 77 and thus selectively the counteracting force determine which exerted on the counteraction gear 74- must be so that this can still perform a movement. The use of a spring 89 ensures that the tuning mechanism 26 does not operate in such a way that the gear 74- is permanently held. With others In words, the spring 89 provides an upper limit to the level of counteracting force that can move the Gear 74- allows, and thus it also determines one upper limit in winding the spring 56.

_ 44-2098A7 / 0SA0

_ 44 -

After the structural details all the components the start and restart mechanism of the invention in the particular application of chainsaws have now been described, it now seems appropriate to include the extremely significant advantages, as well as that to consider the entire aim of the invention in more detail.

A very important advantage of the invention lies in the use of a restart mechanism that enables the allows repeated starting of a warm engine with a minimal amount of stored energy. This diminishes that Weight is significant to the size of the launch mechanism. As a result, the simplicity and security, with which a chainsaw can be handled with this restart mechanism, significantly enlarged.

For example, if a spring 56 requires approximately 20 turns to start a cold chainsaw 5 "to 6 revolutions are already sufficient for starting a warm chainsaw motor with this spring 56.

With this reduction in mass and weight of the chainsaws, there is a simplified one for the operator

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Possibility to restart the chainsaw with one hand, although the chainsaw is not very stable Location is located. Operator safety is ensured by their ability to grasp the saw handle with both hands, while only one or more fingers for the increased Handling of the push button 11 and the starter lever 70b is used.

From known patents such as US Pat. No. 2,987,057, this is the inventive concept Restarting the warm engine with the associated Consideration of the space, the weight and the amount of the stored energy could not be inferred. In this US patent a motor-wound starter mechanism is described which is used in conjunction with an auxiliary recoil starter is used. However, it does not make considerations of restarting the warm engine according to the invention turned on and it appears that the motor winding starter is considered to be the main starting device. The description two starting systems is inexpedient if, on the other hand, advantages as provided by the invention do not occur.

By completely switching off the necessary

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ability of coupling and uncoupling means to avoid of overstressing the restart spring becomes the reliability of the restart mechanism "significantly enlarged. File In addition, the risk of rattling, component breakage and great wear and tear is significantly reduced. These advantages are particularly significant in connection with a chainsaw in which the normal mode of operation tends to generate vibrations.

Here is the US patent mentioned above again mentioned, from which the inventive concept of continuous interlocking can in no way be read.

During the present invention, the idea of the continuous relationship between the components the restart system is based, the known patent describes the use of a decoupling and Re-engagement mechanism.

The display device contributes to the re-start process in an efficient and reliable manner at, in which the operator can determine whether sufficient energy has been collected before attempting to restart has been. Knowing whether the collected restart

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Energy is sufficient, the operator can "determine, o "b the restart wire the recoil start mechanism should be used for starting the engine.

The dividing elements allow for energy collection it allows the operator to make suitable adjustments • which, due to wear and tear of the friction clutch parts, manufacturing differences and differences in ambient temperature become necessary can.

The invention has been described in connection with a preferred embodiment of a chainsaw and can of course experience various modifications in the area of application as well as in constructional details, which are to be covered by the following protection request.

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Claims (6)

PATENT CLAIMS 1. Device in a chainsaw or other portable tool with chainsaw motor, cutting elements driven by this motor and starting elements to start the chainsaw motor while this motor is cold and at a temperature below the normal working temperature, marked by running chainsaw motor (4) of the starting elements (23) independently operating restart means (24) for storage an amount of energy sufficient to restart the chainsaw motor (4) at normal operating temperature, whereby the amount of energy is sufficient to restart the chainsaw motor when the chainsaw motor is warm and on normal operating temperature and insufficient to start when the engine is cold and essentially is below normal operating temperature, by stop means (11) for stopping the chain saw and by means (70> 58, 63) to use this stored amount of energy, which is not sufficient for starting a cold engine, - 49 209847/0640 however, the chainsaw motor (4) starts again when it is warm and essentially at a normal operating temperature is. 2. Apparatus according to claim 1, characterized in that the restart means (24) from continuously operating Producer means (43) consist of the restart energy for the chainsaw motor (4) generated from Energe storage means (56) for storing the energy generated by the generating means (4J) to that in the energy storage means (56) the amount of energy collected is sufficient to restart the chainsaw motor if the Engine is warm and at normal operating temperature, but not sufficient to start the cold engine, from Enesgieverteiler-Mittein (73) with energy-transmitting Counteraction means (74) engaged with the energy storage means and while they are relative to the Energy storage means are retained, energy is transferred from the generating means to the energy storage means, and with a friction clutch which is in yielding and frictional connection with the counteracting means (76), said power distribution means (73) being capable of starting a cold engine after storing it insufficient amount of energy from the storage means - 50 - 209 847/0640 (56) the energy of the generating means (43) during the to divert continuous progress of the chainsaw motor (4) and the generating means (43) from means (54, 47, 75) for triggering the energy distribution of the distribution means (73) depending on the energy storage means amount of energy collected, whereby after appropriate collection the counteractive means for an energy transfer from the generating means to the storage means through the movable resilience of the Counteraction means are prevented relative to the friction clutch, from means (77)? cLie the friction clutch (76) keep constantly in a frictional, yet yielding connection with the counteracting means (74), and of means (47,) which the producer means (43) are in continuous communication with both the energy storage means (56) and the counteracting means (74). 3. Apparatus according to claim 2, characterized by means (81, 84, 83) for indicating that the storage means (56) in the. The chainsaw has not yet received a sufficient amount of energy from the production funds (43), by means (81, 84, 82) for indicating that the storage means (56) in the chain saw has a sufficient amount of energy owns and that the energy from the producer means - 51 209847/0640 (4-3) is diverted to the energy distribution means (73), and means (85) for adjusting the friction clutch for selective adjustment of the level of through the storage elements in the chainsaw accumulated amount of energy. 4 ·. Device according to claim 1, characterized by a spring (56) which, after being tensioned and released, starts the chainsaw motor (4-) by a first gear (5 * 0 with a first number of gear teeth, through a second gear (75) with a second, different from the first differentiating number of gear teeth, through a gear (4-7), which is drivingly with the first and second gear is in connection and depending on the operation of the chainsaw motor (4-) a rotation movable gear (54-, 75) caused, wherein the first gear (54-) is connected to the spring (56) and on the Spring which transmits tension energy, and through a detachable Friction clutch (76) which is clutch-wise connected to the second gear (75), the second Gear (75) when held by the friction clutch (76) represents a counteraction means (74 ·) and via the gear (4-7) one turn on the first gear (54-) transmits, and when movement is released by the releasable - 52 209847/0640 Friction clutch (76) the transmission in a rotary motion transmission on the first gear (54) to tension the leather. (56) prevents the releasable friction clutch (76) allows a rotation of the second gear (75) in order to allow the second gear (75) to rotate first gear (5 * 0 depending on the degree of tension to prevent the spring (56). 5. Device according to claim 4, characterized in that that display means (78) in a coupling type connection with both the first (54) and the second Gear (75) stand that the means (83, 84) the movement of the display means (78) as a function of the movement of the Gear wheels (54, 75) to detect incomplete spring tension and that the means (82, 84) indicate the movement of the display means (78) as a function of the movement of the second gear (75) to identify the end of the spring winding process. 6. Apparatus according to claim 4, characterized in that the limiting elements (85) for the stored Amount of energy with the friction clutch (76) are connected in such a way that this selectable the second gear (75) depending on different levels of the in the spring - 53 -2098A7 / 06A0 (56) releases stored energy. 7 · Procedure for starting and restarting a
Chainsaw "in which a« chainsaw engine is started as long as it is cold and below a normal operating temperature and the cutting process is started by the chainsaw ", characterized in that, during
the chainsaw engine is running, one to restart
of the chainsaw motor "a sufficient amount of energy is stored at a normal working temperature, this amount being sufficient to restart the motor,
when it is warm and at a normal working temperature, and this amount of energy is not sufficient to start the engine, when it is cold and is at a temperature that is significantly below the normal working temperature, that the chainsaw is stopped and that the stored For a cold engine start, an insufficient amount of energy is used to restart the chainsaw engine when this engine is warm and at essentially normal operating temperature. 209847/0640