DE202011000616U1 - Starting device for internal combustion engines - Google Patents

Abstract

Starter device (100) for at least one internal combustion engine, in particular cable starter device for at least one two-stroke or four-stroke engine, with at least one cable pulley or cable drum (17) rotatably mounted in a housing (10), which is used to generate a drive torque for a crankshaft by means of at least one starter grip or Pull handle, via at least one power transmission means, in particular via a starter rope or pull rope, can be set in rotation and is connected via at least one coupling member (26) to at least one driver member, in particular to at least one pawl driver, by means of which the drive torque can be transmitted to the crankshaft and that The coupling member (26) is in engagement with the driver member and with the pulley or the cable drum (17) and the power transmission means, characterized in that the coupling member has an energy storage section and a deflection section.

Description

Technical area

The invention relates to a starting device for at least one internal combustion engine, in particular cable pull start device for at least a two-stroke or four-stroke engine, with at least one rotatably mounted in a housing pulley or cable drum, for generating a driving torque for a crankshaft by means of at least one Anwerfergriffs or pull handle, about at least one force transmission means, in particular via a starter rope or traction cable, rotatable and at least one coupling member with at least one driver member, in particular with at least one pawl, connected by means of which the drive torque is transferable to the crankshaft, the coupling member with the driver member and with the pulley or the cable drum and the power transmission means is engaged.

State of the art

The operation of a starting device for an internal combustion engine, in particular a cable start device for an internal combustion engine, in particular for a two-stroke or four-stroke engine, often caused problems in the past, because when starting by the compression in the engine periodically high reaction forces occur, whereby changing and passing very high forces act on the hand of the operator.

To reduce the transmission of these particularly strong, caused by the compression in the engine reaction forces on the handle of the starting device and thereby facilitate the starting process is, for example, in the DE 41 35 405 proposed to elastically cushion the fluctuations of the applied torque to the crankshaft.

For this purpose, between the power transmission means, in particular the Anwerferseil or pull rope, the handle associated pulley or cable drum and the driver member, in particular the jack driver, the crankshaft an elastic member interposed, by means of which mediated by handle and power transmission train movement during the starting process of the above-mentioned variations something or completely freed.

In starting devices for engines of high cubic classes, for example above 50 cm ³ , starting forces of 300-700 N or 30-70 kg are often achieved in the starting device. However, forces of 100-250 N or 10-25 kg are desirable.

In the DE 297 10 169 U1 we described a starting device for an internal combustion engine, in which a crankshaft gear via a first gear meshes with a starter gear, so that the transmission for starting the internal combustion engine can be optimally lived out.

Also from the US 5,111,707 is a starting device is known which has a transmission as a coupling member.

In the DE 301 064 a spring-loaded device for explosion engines is described, in which the rotating spring housing causes the engine to crank while the running engine tightens the spring again.

Disclosure of the invention

Proceeding from this, it was an object of the present invention to provide a device with the same time a force-reduced and harmonic starting forces course is possible.

This object is achieved by the feature combination specified in claim 1.

According to the invention, a starting device for at least one internal combustion engine is now provided, with at least one pulley or cable drum rotatably mounted in a housing, for generating a drive torque for a crankshaft by means of at least one ejector handle or pull handle, via at least one power transmission means, in particular via a starter cable or pull rope, is rotatable and connected via at least one coupling member with at least one driver member, in particular with at least one pawl, by means of which the drive torque is transferable to the crankshaft and the coupling member is in engagement with the driver member and the pulley or the cable drum and the force transmission means and wherein the coupling member has an energy storage section and a deflection section.

The force to be applied, ie the force curve during starting, is subject to high force changes due to the compression and relaxation phases of the engine.

According to the present invention, however, a harmonic force curve is achieved at startup by the energy storage causes a smoothing (the force peaks are capped). By the deflection section can according to the present Invention of the entire force curve paralell, moved to a lower level of force or lowered.

The combination of energy storage with Umlankabschnitt can now therefore cause a power-reducing and harmonious starting power course, which brings a great advantage especially for engines with cubic classes of more than 50 ^cm3.

Due to a new carburettor and ignition technology, a lower number of revolutions of currently approx. 5 revolutions of the engine to <5, preferably 2 to 3, is necessary for starting.

According to a preferred embodiment of the present invention, the energy storage portion comprises or is formed as a three-dimensional spring. Such provided energy storage can be relatively easily integrated into the device.

The spring can have a wire-wound three-dimensional spring, preferably one whose first winding has a smaller cross-sectional area than a subsequent winding. A cross-sectional area here is to be understood as the area enclosed by a turn.

With an embodiment of the starting device according to the invention, it is now possible for a load of the spring, it comes first from a certain strength on the bearing journal of the starter housing to the plant.

By this configuration, a breakage of the spring, which usually occurs at overload at this point, can be prevented, since the first smaller spring coil comes to rest on the journal of the housing.

Thus, it is possible by such a modified embodiment of the coupling member according to the invention, without further component changes, to prevent overloading of the coupling element.

In such an embodiment of the coupling element whose tapered shape follows the incoming cooling air flow of the ventilation elements of the housing.

With an embodiment according to the invention a significantly improved cooling of the internal combustion engine downstream of the starter is achieved, since the cooling air inflow is improved in the arranged behind the starter fan and thus a good flow of a pole wheel can be achieved.

Another advantage of using a spring wound from wire, the cross-sectional areas of which is substantially smaller from the second turn to the other end, that also the space requirement in the starter is lower.

It is according to the present invention not necessary that the spring is formed in a circular shape and thus as a truncated cone. Rather, all possible wound forms with tapered cut surfaces, such as truncated pyramids, Tetraederstümpfe, etc. conceivable. Likewise, a truncated cone shape with elliptical cross-sectional areas or a truncated pyramidal shape with polygonal cross-sectional areas would be conceivable.

According to a particularly preferred embodiment of the present invention, the deflection section comprises a deflection gear, preferably variable.

This deflection gear is in accordance with a particularly preferred embodiment, a force-reducing transmission.

Preferred embodiment of the invention

An embodiment of the invention will be explained below with reference to the drawing. Show it:

1 a schematic exploded view of a starting device according to the prior art;

2 a schematic representation of the starting device 1 ;

3 a schematic exploded view of a starting device according to a first preferred embodiment;

4a) a schematic representation of the starting device 3 as in 4b) a section along AA;

5 a schematic exploded view of a starting device according to another preferred embodiment; and

6a) a schematic representation of the starting device 5 and as well 6b) a section along AA.

In the representations of the prior art and the embodiment shown, the corresponding elements are designated by the same reference numerals, wherein the reference numerals of the prior art are provided with an apostrophe.

In 1 and 2 is a starting device 100 ' represented as known from the prior art. Such a starting device 100 ' is, as well as in 3 to 6 illustrated starting device 100 intended for manually starting an internal combustion engine, which belongs for example to a motor chain saw. The cable start device 100 . 100 ' is in a housing 10 . 10 ' housed in the embodiment according to the prior art ( 1 and 2 ) a removable with vents 11 ' provided lid of the motor housing is. From the inner wall of the housing 10 . 10 ' go a journal 14 . 14 ' (only in 1 . 2 and 5 visible), that of a likewise substantially housing-fixed spring housing 15 ' for a spiral, at the edge of the spring housing 15 ' cantilevered starter spring 16 ' is surrounded. This starter spring 16 ' serves as a return spring for the pulley or rope drum 17 . 17 ' ,

On the pulley or rope drum 17 . 17 ' is as Kraftübertragungsmittel a starter rope or pull rope (not shown) wound, the free end of the housing 10 . 10 ' led out and attached to a handle. By pulling on the starter rope by means of the handle is the pulley or rope drum 17 . 17 ' under settlement of the starter rope or pull rope around the bearing pin 14 . 14 ' set in motion.

The pulley or rope drum 17 . 17 ' has a bearing pin 14 . 14 ' surrounding annular reception space 20 . 20 ' on, in which a spiral spring 26 . 26 ' is arranged and with a ratchet driver member 25 . 25 ' engaged.

The outer, that is the pulley or rope drum 17 . 17 ' facing end of the coil spring 26 . 26 ' is in a slot as shown in the prior art 27 ' hung in an annular shoulder of the pulley or rope drum 17 ' is provided. This paragraph encloses the coil spring 26 ' whose outer winding bears against the inner wall of the shoulder. That the latch driver member 25 ' facing end of the coil spring 26 ' is in the latch driver member 25 ' stored.

In the assembled state of the starting device 100 . 100 ' passes through the bearing pin fixed to the housing 14 . 14 ' a central bore of the end wall of the pulley or rope drum 17 . 17 ' , so that this center hole a bush-shaped receptacle for the journal 14 . 14 ' forms. In an axial internal thread of the journal 14 . 14 ' is a fixing screw 28 . 28 ' screwed in, at the head of the pawl driving member 25 . 25 ' is attached.

If the pulley or rope drum 17 ' According to the embodiment of the prior art, by pulling on the starter rope or pulling rope is set in rotation, takes the pulley or rope drum 17 ' over the coil spring 26 ' the latch driver member 25 ' With. By means of this latch driver link 25 ' So is the rotational movement of the pulley or rope drum 17 ' and thus the torque transferable to the driven crankshaft.

The spiral spring 26 ' as they are in 1 According to the prior art, represents a cylindrical coil spring and thus is also the pawl carrier member 25 ' trained accordingly.

Unlike in 1 and 2 illustrated embodiment according to the prior art is the spring 26 according to the preferred embodiment shown 3 and 4 and also 5 and 6 not with the pawl driver link 25 connected, but with a first transmission part 29 , This first transmission part 29 is at least with another transmission part 30 in engagement and this further transmission part is in turn directly or indirectly with the ratchet driver member 25 engaged.

The 3 . 4 and 5 . 6 show different embodiments of the transmission parts 29 . 30 ,

It is in the 3 the transmission is designed as a planetary gear. The planetary gear includes a sun gear 31 , the ring gear 30 , three planet wheels 32 and the planet carrier 33 , At the planet carrier 33 is a small corner of one of the cones that can ever be seen in a planetary gear 32 intervention.

The driver to the flywheel 25 who also in 5 is different in shape from the driver 25 ' in 1 , The function is the same.

LIST OF REFERENCE NUMBERS

100/100 '

starter

10/10 '

casing

11 '

vents

12

hook

14/14 '

pivot

15/15 '

spring housing

16/16 '

starter spring

17/17 '

Pulley or rope drum

20 '

Reception room of the pulley or rope drum

25/25 '

pawl driver

26/26 '

spiral spring

28/28 '

fixing screw

29

first transmission part

30

another gear part / ring gear

31

sun 31

32

planet

33

planet carrier

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4135405 [0003]
• DE 29710169 U1 [0006]
• US 5111707 [0007]
• DE 301064 [0008]

Claims (7)

Starting device ( 100 ) for at least one internal combustion engine, in particular cable pull start device for at least one two-stroke or four-stroke engine, with at least one in a housing ( 10 ) rotatably mounted pulley or rope drum ( 17 ), for generating a drive torque for a crankshaft by means of at least one Auswerfergriffs or pull handle, at least one power transmission means, in particular via a starter rope or pull rope, set in rotation and at least one coupling member ( 26 ) is connected to at least one driver member, in particular with at least one latch driver, by means of which the drive torque is transferable to the crankshaft and the coupling member ( 26 ) with the driver member and with the pulley or the cable drum ( 17 ) and the power transmission means is engaged, characterized in that the coupling member has an energy storage portion and a deflection portion. Starting device ( 100 ) according to claim 1, characterized in that the energy storage portion comprises a three-dimensional spring. Starting device ( 100 ) according to claim 2, characterized in that the spring comprises a wire wound three-dimensional spring, preferably one whose first winding has a smaller cross-sectional area, than a subsequent winding. Starting device ( 100 ) according to one of the preceding claims 2 and 3, characterized in that the cross-sectional areas of the spring ( 26 ) substantially shrink. Starting device ( 100 ) according to one of the preceding claims, characterized in that the deflection section comprises a deflection gear, preferably variable. Starting device ( 100 ) according to one of the preceding claims, characterized in that the deflection gear is a force-reducing transmission. Starting device ( 100 ) according to one of the preceding claims, characterized in that the wound spring ( 26 ) of the second of the pulley or rope drum ( 17 ) facing winding to a tapered coil spring.

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