DE202011000519U1 - Engine working device with an internal combustion engine - Google Patents

Abstract

Motor working device (100) with an internal combustion engine (10) with a carburetor with a choke valve (11) and an ignition module (12) and a sensor element (30) for detecting the speed of the internal combustion engine (10), in particular the rotor rotation angle per unit of time, characterized in that that an adjusting device (21) controlled by the ignition module (12) is provided for the choke valve (11).

Description

The invention relates to an engine working device with an internal combustion engine having a carburetor with a choke flap and an ignition module and a sensor member for detecting the rotational speed of the internal combustion engine, in particular the Polraddrehwinkels per unit time.

Furthermore, the invention relates to a method for starting the internal combustion engine.

Engine working tools, such as chainsaws or comparable portable handsets, are equipped with small internal combustion engines, mostly two-stroke engines, which have to be relatively simple and compact for weight reasons.

Different types of carburetor control principles have become established in engine tools. However, all have a similar handling with respect to the designated choke or choke flap starter flap. During cold start the choke is closed. Once the first ignition is done, the choke is to open, with the throttle in half-throttle position continues to boot. The choke lever is often referred to as a choke, and serves to control the choke function.

On a warm start, however, without choke, d. H. with opened starter flap, but started directly with half throttle. In usual operating concepts, this means a manual insertion of the choke (closing the choke valve) and "automatically half throttle", in which case the choke is to be taken back. This can easily cause operator error. It can be confused with a Chokestellung, so that z. B. trying to start without choke. Or it can be forgotten to take back the choke after ignition, d. H. partially or completely open the starter flap.

State of the art

From the DE 10 2008 059 289 A1 is a portable hand-held working device known, which supplies a fuel / air mixture to an internal combustion engine via an intake passage. The intake opens into a crankcase, wherein a choke flap is arranged in the intake passage. In a main fuel passage, an electromagnetic switching valve is arranged, via which the fuel in the fuel passage is controllable.

The WO 2007 133 125 A1 shows and describes a two-stroke engine with a device for changing the air-fuel mixture. An electromagnetically operable valve for changing the air-fuel mixture can be controlled by a control unit. The control unit is connected to a temperature sensor to optimize engine operation.

DESCRIPTION OF THE INVENTION: Problem, Solution, Advantages

The invention has for its object to provide a motor work tool that can be started in a simple and convenient way, with operator error should be avoided.

This object is achieved in that an adjustment device controlled by the ignition module for the choke flap (choke) is provided.

The inventive interaction between the ignition module and carburetor is achieved in an advantageous manner that the choke is automatically opened during the startup process. In addition, this interaction ensures that the starting process for the operator of the device is simplified.

By the invention it is possible to avoid errors when starting. In this case, the machine starts and the user no longer has to take their hands off the grips to engage the choke lever, i. H. to set the lever for the starter flap. This is particularly relevant for hand-held implements such as chainsaws, as even a partial or short-term release of the handles could lead to accidents.

Before starting, the user only operates the choke half-throttle lever once. Then the boot process will be initiated automatically.

Further advantageous embodiments of the invention are characterized in the subclaims.

In an advantageous development of the engine operating device according to the invention, it is provided that the ignition module and / or an engine component and / or an implement component have an integrated temperature sensor for detecting the temperature of the internal combustion engine and / or the ambient temperature. Preferably, the temperature sensor and / or a temperature sensor circuit for detecting a cold or warm start of the internal combustion engine is designed so that the choke valve is designed to be actuated in response to a temperature detection of the temperature sensor and / or a temperature sensor circuit. The ignition module now monitors the Polraddrehwinkel or the time window per revolution. According to various criteria, the ignition module detects that a first ignition has occurred and gives a signal to the carburetor or to the Carburetor periphery for opening the choke flap. The user continues the starting process unhindered until the machine now starts with half throttle. In the case of a warm start, which detects the ignition module through the integrated temperature sensor, the choke is equal to the first train at z. B. a pull starter opened.

Therefore, it is very advantageous if a detection device for detecting a Polradwinkels and / or a Polradgeschwindigkeit of the internal combustion engine is present, which detects magnetic passages on the ignition module.

This pole wheel monitoring is particularly suitable when an ignition coil and / or a star pull starter with a winding drum are arranged. Alternatively, the detection device could also be designed for direct detection of the drum revolutions during starting.

The ignition module monitors a Polradwinkel of the internal combustion engine preferably in response to a number of Polradumdrehungen or a Polradgeschwindigkeit. The choke flap will open automatically after a while. For the starting process is on the cable drum a rope for z. B. 5 turns (3 to 10 turns are useful). If there is still an increase in speed after the fifth revolution (magnetic passes through the ignition module), there must have been an ignition.

An alternative criterion for the ignition made could be the pole wheel speed. If the flywheel speed is greater than the maximum speed to be reached per cable, ignition must be completed.

In order for the choke flap always to assume a correct position both before a starting operation and directly after the starting process without manual intervention by a user, the choke flap is automatically actuated by an electromagnetic drive, in particular by a lifting magnet. The solenoid therefore automatically opens and closes the choke flap depending on the engine temperature. As a result, a manual choke flap operation is never necessary. At least the solenoid opens the choke flap.

Alternatively, the solenoid could only have a unlatching, unlocking or a similar function for the choke valve. In this embodiment, the user must mechanically insert choke half gas. It could be provided that after the stop of the engine or after the last turn done choke and half gas must always be inserted. Here, the use of a spring would be appropriate, so that this insertion takes place against the spring force and energy is stored. Ie. in the inserted choke position the choke flap latches. As soon as the starting process begins, the ignition module analyzes the situation with regard to cold start and warm start and opens the choke flap immediately or only after the first ignition, controlled by means of the lifting magnet or by a voltage supply from the ignition module. Therefore, the adjusting device may comprise a drive or even an unlocking device. A combination of both solutions is possible.

In a further advantageous embodiment of the invention, a half-throttle function is coupled to the choke or the choke flap. This has proven very successful with hand-held implements. Due to the half-throttle function, the start is made much easier, without any additional operation of the throttle lever by the user would be required. In combination with the invention, the user only has to pull the cable to start the device. So he does not have to worry about a gas position, d. H. a throttle position still worry about a motor temperature or Chokestellung. Through the use of the solenoid is an automatic switch to an environmentally friendly idle.

According to the invention, a method is provided for starting the internal combustion engine of the engine tool in which an engine state detection step is present at start, wherein in the engine state detection step, a warm start or a cold start is detected, wherein in the case of a cold start z. B. is started automatically with a choke or with closed choke flap and is automatically started in the case of a warm start without a choke or with closed choke flap.

For this purpose, semi-automatic or fully automatic systems can be selected. In both cases, the choke is automatically opened during cold start during startup.

So that the choke is set correctly during the restart, it is provided according to an advantageous embodiment of the method according to the invention that after a stop of the internal combustion engine, the choke is automatically activated or the choke flap is closed.

A structurally very simple to implement solution is that a warm start is detected and is automatically withdrawn by spring action before a first start of the internal combustion engine after manually inserting the choke of the choke. Alternatively, the activation of a lifting solenoid valve may be provided.

A further advantageous variant of the method is that before a first start of the internal combustion engine after manual or automatically activated insertion of the choke at the first train on the starter rope detected a warm start and the choke is automatically withdrawn, in particular by spring action.

Best way to carry out the invention

An embodiment will be explained in more detail with reference to the drawings, wherein further advantageous developments of the invention and advantages thereof are described. Show it:

1 a schematic representation of an internal combustion engine of a hand-held implement,

2 a schematic representation of a first embodiment of a choke device,

3 a schematic representation of a second embodiment of the choke device,

4 a schematic representation of the hand-held implement,

5 a flow chart for a cold start, and

6 a flow chart for a warm start.

1 shows an internal combustion engine 10 a motorized working device. In 4 is the engine tool 100 shown as a chainsaw.

The internal combustion engine 10 is with a carburetor 19 , with a choke flap 11 and a throttle 11a and an ignition module 12 Mistake. Furthermore, the internal combustion engine comprises 10 a sensor member 30 for detecting the rotational speed of the internal combustion engine or the Polraddrehwinkels per unit time, wherein the sensor dress 30 ' in the ignition module 12 can be integrated.

Further shows 1 a crankcase 13 , a piston 14 , a cylinder 15 , a spark plug connected to the ignition module 16 , an outlet channel 17 with a silencer 18 as well as the carburetor 19 to provide a fuel-air mixture in which the choke flap 11 and the throttle 11a are arranged. The fuel supply via a nozzle is included 20 indicated. The choke flap 11 or the choke is coupled to a half-throttle function. The basic arrangement and components of the illustrated two-stroke engine, such as connecting rod, carburetor body, filter elements u. Like. Are well known and are therefore not explained in detail.

2 shows one from the ignition module 12 controlled adjusting device 21 for the choke flap 11 , The adjusting device 21 is z. B. with a control line 22 with the ignition module 12 connected and as a solenoid 23 executed or with a solenoid 23 Mistake. The lifting magnet 23 is with an actuator 24 connected, which causes an opening and closing of the choke flap. The adjusting device 21 in 2 is an electromagnetic drive.

Furthermore, the ignition module 12 with a built-in motor temperature sensor 25 for detecting the temperature of the internal combustion engine 10 connected. Alternatively or additionally, the temperature sensor 25 or an additional sensor (only) to detect the ambient temperature. The temperature sensor 25 can be integrated in an engine component and / or in an implement component. The temperature sensor 25 or a temperature sensor circuit is used to detect a warm start of the internal combustion engine. This is the choke flap 11 depending on the temperature detection of the temperature sensor 25 through the adjusting device 21 actuated.

One the sensor link 30 comprising detecting means for detecting the Polradwinkels, more precisely, the Polradgeschwindigkeit the internal combustion engine (Polraddrehwinkel per unit time).

As the 3 illustrates, the adjustment 21 an unlocking device 26 include. The choke flap 11 is with an actuator 24 ' connected with a spring 27 , z. B. a tension spring is in operative connection. The unlocking device 26 can be a latch or nose 28 have, so by a solenoid 23 ' the adjustment 21 the cocked spring 27 can be released.

As 4 shows, the implement has a pull starter 31 with a rope 32 and a winding drum 33 on. The detection means for detecting the Polradwinkels detects the drum revolutions when starting the engine.

The 5 and 6 show a boot process in cold ( 5 ) and in warm ( 6 ) Engine condition.

At the cold start (step S10), choke and half throttle are manually set (step S11) and the engine with the starter rope 32 started (step S12). The starter rope 32 has a length of z. B. five turns on the pulley or winding drum 33 , If an acceleration of the engine after the five turns, the engine will run. Therefore, the detector counts the revolutions or a comparable size of the winding drum. Alternatively, the pole speed can also be detected. Namely, if the speed of the fan wheel is higher than the maximum speed of the starting operation, it can be assumed that the engine is running.

This engine state or the start of the engine detects the ignition module 12 , In step S14, the choke flap is released, automatically by the adjusting device 21 (Magnetic valve). Subsequently, the engine is running without choke (step S15).

Additionally or alternatively, after the stop of the engine, choke and half gas can be automatically activated by the activation spring 27 which ensures the required release. The engine is then ready for a reboot.

In 6 the warm start of the engine is performed (step S20). Again, choke and half gas are activated. In step S21, the choke flap is closed. The start (S22, S23) thus takes place without choke.

• – Choke-Halbgas einlegen
• – Seilzugstarter betätigen bis Maschine läuft.

For the user, the handling is simplified according to a first variant of the invention, because there is only one start algorithm, namely:

• - Insert choke half gas
• - Actuate pull-starter until the machine is running.

Behind this operation hide the following processes:
The cold start is done with choke and half gas. After the first ignition, the choke is opened and it is started with half throttle.

The invention provides a detection of a warm start, then immediately the choke is opened and starting only with half throttle continued operation. Appropriately, there is a recognition of (at least) the first revolution with the ignition.

This operation can be combined with the so-called "touch-off". In this case, the user no longer needs to operate a switch before starting. The machine is always ready to start.

By integrating queries or a query algorithm (eg with a computer program or microprocessor) into the ignition module 12 and creating an interaction between ignition module 12 and the carburetor, it is possible that the user of the machine always choke and half gas before starting. During the starting process then decides the ignition module 12 whether it is a cold or warm start. Next decides the ignition module 12 during startup, when the first ignition has occurred and automatically opens the choke flap.

in the second embodiment of the invention, the user does not even need to insert choke half gas. The machine is always ready to start. This is achieved by the lifting magnet 23 according to 2 Choke semi-gas is automatically inserted or removed depending on the engine temperature before and after take-off.

LIST OF REFERENCE NUMBERS

100

Engine working machine

10

Internal combustion engine

11

choke

11a

throttle

12

ignition module

13

crankcase

14

piston

15

cylinder

16

spark plug

17

exhaust port

18

silencer

19

carburettor

20

Fuel supply

21

adjustment

22

control line

23, 23 '

solenoid

24

actuator

25

temperature sensor

26

unlocking

27

feather

28

nose

29

30, 30 '

sensor element

31

pullstarter

32

starter rope

33

winding drum

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 102008059289 A1 [0006]
• WO 2007133125 A1 [0007]

Claims (8)

Engine tool ( 100 ) with an internal combustion engine ( 10 ) with a carburettor with a choke flap ( 11 ) and an ignition module ( 12 ) and a sensor member ( 30 ) for detecting the rotational speed of the internal combustion engine ( 10 ), in particular the Polraddrehwinkels per unit time, characterized in that one of the ignition module ( 12 ) controlled adjusting device ( 21 ) for the choke flap ( 11 ) is provided. Engine working device according to claim 1, characterized in that the ignition module ( 12 ) and / or an engine component and / or an implement component an integrated temperature sensor ( 25 ) for detecting the temperature of the internal combustion engine ( 10 ) and / or the ambient temperature. Engine working device according to claim 2, characterized in that the temperature sensor ( 25 ) and / or a temperature sensor circuit for detecting a cold or warm start of the internal combustion engine ( 10 ) are executed, so that the choke flap ( 11 ) in dependence of a temperature detection of the temperature sensor ( 25 ) and / or the temperature sensor circuit is executed operable. Engine working device according to one of the preceding claims, characterized in that a detection device, in particular with the sensor member ( 30 ), for detecting a Polradwinkels and / or Polradgeschwindigkeit the internal combustion engine ( 10 ), the magnet passages on the ignition module ( 12 ) detected. Motor work tool according to one of the preceding claims, characterized in that a pull starter ( 31 ) with a winding drum ( 33 ) is arranged, wherein a detection device for detecting the drum revolutions is present at the start. Engine working device according to one of the preceding claims, characterized in that the choke flap ( 11 ) by an electromagnetic drive, in particular by a lifting magnet ( 23 ) is carried out actuated. Engine working device according to one of the preceding claims, characterized in that the adjusting device ( 21 ) a drive and / or an unlocking device ( 26 ). Engine working device according to one of the preceding claims, characterized in that with the choke or the choke flap ( 11 ) a half-gas function is coupled.

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