This present invention relates to the field of carburetor, in particular, relates to a fuel enrichment simple starting device and method of carburetor, using pre-injection technology to achieve engine fuel enrichment start, That is, in the first step squeeze the purge bulb, pre-inject the quantitative fuel, and then use the choke of the large volume air to achieve simple start, steps: the first step, squeeze the purge bulb; the second step, close the choke; the third step, pull the engine starter to the engine running; the fourth step, increase and decrease the throttle to normal running. If using the fuel enrichment simple starting device and method of carburetor in the present invention, the engine can be started completely by above four steps, the starting device has the advantages of simple operation, less starting times and easy to start at low temperature (such as 0 C.).

An ignition system of a combustion engine has a start-up adjustment curve with a maximum rotational speed, an operating adjustment curve and a switch-over device for switching between curves. The start-up adjustment curve is selected in the case of a start-up of the combustion engine. A rotational speed curve is divided into adjacent cycles. The start of the first cycle is the point in time of the second ignition after the start-up and the start of the subsequent cycles is in each case the point in time of ignition at which the rotational speed is less than in the case of the subsequent point in time of ignition. The criterion for switching to the operating adjustment curve is whether the average of the rotational speeds of successive cycles differs by less than a first tolerance value.

An ignition system of a combustion engine has a start-up adjustment curve with a maximum rotational speed, an operating adjustment curve and a switch-over device for switching between curves. The start-up adjustment curve is selected in the case of a start-up of the combustion engine. A rotational speed curve is divided into adjacent cycles. The start of the first cycle is the point in time of the second ignition after the start-up and the start of the subsequent cycles is in each case the point in time of ignition at which the rotational speed is less than in the case of the subsequent point in time of ignition. The criterion for switching to the operating adjustment curve is whether the average of the rotational speeds of successive cycles differs by less than a first tolerance value.

The invention relates generally to portable internal combustion engine powered devices. Public a small engine control combination switch comprising a knob assembly, a bracket and a choke cable, knob assembly includes a fixed plate, characterized in that the fixed plate with a rail; the bracket including a first hole. The choke cable connects with the rail through the first hole. The height of the rail is gradually increased, rail pivot drives the choke cable on the top of the track moves up and down; also further includes a fuel switch, a fixed plate is provided with a rotating shaft, the shaft connecting the fuel switch. The invention through the choke point of engine control, start-up, operation and shut down control, which simplifies the traditional steps of engines, generators and other equipment, greatly simplifying the operation process, improving the operation efficiency.

A handheld work apparatus has a combustion engine which drives a tool of the work apparatus via a centrifugal clutch. The centrifugal clutch couples in an engagement rotational speed range (n.sub.K) which extends between a lower engagement rotational speed (n.sub.u) and an upper engagement rotational speed (n.sub.o). The engine has a fuel supply device, an ignition device, a control device and a device for detecting the rotational speed (n) of the engine. A method for operating the handheld work apparatus makes provision for the rotational speed profile of the combustion engine to be monitored in the engagement rotational speed range (n.sub.K) and for the power (P) output for driving the tool to be increased from an operating power (P.sub.1) to an increased power (P.sub.2, P.sub.3) when the rotational speed profile corresponds with a predetermined rotational speed profile over a predetermined period of time (?t).

A carburetor with a throttle valve is provided in which a linkage member is in communication with the throttle valve. An idle down handle can be moved from an unactuated position to an actuated position and is in communication with the throttle valve. Movement of the idle down handle to the actuated position causes the throttle valve to be placed into the closed position. When the idle down handle is in the unactuated position the throttle linkage member can cause the throttle valve to be moved back and forth between the open and closed positions.

A carburetor with a throttle valve is provided in which a linkage member is in communication with the throttle valve. An idle down handle can be moved from an unactuated position to an actuated position and is in communication with the throttle valve. Movement of the idle down handle to the actuated position causes the throttle valve to be placed into the closed position. When the idle down handle is in the unactuated position the throttle linkage member can cause the throttle valve to be moved back and forth between the open and closed positions.

A carburetor including a one piece choke valve and shaft assembly including a shaft, a detent plate formed on a first end, a lever arm formed on a second end, a pair of opposing collars formed adjacent the detent plate and lever arm, a valve plate centrally positioned on the shaft, and opposing splines formed on the shaft enabling it to be inserted through an assembly slot cut into a shaft bore in the carburetor body. The detent plate includes a partial annular slot encompassing the angular range of travel of the choke valve. First, second and third detent pockets are formed along an outer edge of the slot. A positive positioning pin engages or interacts with the detent plate to positively position the choke valve in first, second or third angular positions corresponding to close choke, half choke and open choke.

A carburetor including a one piece choke valve and shaft assembly including a shaft, a detent plate formed on a first end, a lever arm formed on a second end, a pair of opposing collars formed adjacent the detent plate and lever arm, a valve plate centrally positioned on the shaft, and opposing splines formed on the shaft enabling it to be inserted through an assembly slot cut into a shaft bore in the carburetor body. The detent plate includes a partial annular slot encompassing the angular range of travel of the choke valve. First, second and third detent pockets are formed along an outer edge of the slot. A positive positioning pin engages or interacts with the detent plate to positively position the choke valve in first, second or third angular positions corresponding to close choke, half choke and open choke.

Proposed is a throttle valve apparatus for an internal combustion engine, with a housing and an intake pipe comprising a through-flow cross section and a throttle valve that is pivotable relative to the through-flow cross section, which is actuatable by means of a throttle valve shaft and with an actuating device arranged on the housing, by means of which the throttle valve can be releasably fixed in a cold starting position in which the through-flow cross section is at least partially opened.