JPS59194067A - Starter of float type carburetter for portable work engine - Google Patents

Abstract

PURPOSE:To ensure simple starting by providing an injection tube of a starting fuel pressure-sending pump provided under the oil surface of fuel to face to a hole at the lower end of a fuel nozzle for facilitating to increase the fuel at the time of starting. CONSTITUTION:In a carburetter in a portable work engine for a mower and the like, a fuel nozzle 3 is provided to be opened to a Venturi 2 of a carburetter main body 1. Another end of the fuel nozzle 3 is opened in a float chamber 4 via an orifice. In the float chamber 4, fuel is contained to maintain a fixed oil face 8 constantly by opening and closing a float valve 6 linked with a float 7. At this stage, an injection tube 15 is positioned to face to a lower end hole 14 of the fuel nozzle 3 opened in the float chamber 4. The injection tube 15 is connected to a pressure-sending pump 11 including a pump button 13 manually operated via a joint 12. When the button 13 is pushed, increased fuel is injected into a carburetter from the fuel nozzle 3 for facilitating the starting of the engine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a starting device for a float type carburetor for a portable working machine engine.

Portable working machines come in hand-held, shoulder-carrying, and backpack-type types depending on the purpose, and are widely used in forestry, agriculture, gardening, etc., such as brush cutters, lawn mowers, pruning machines, and pruning machines. A two-stroke engine is used because it is small and lightweight and requires inclined operation, and a centrifugal clutch-type rotation transmission device is used for workability.Also, due to the nature of the work, it is often used in spring, summer, autumn, and during the cold winter months, it is extremely cold. It is well known that the use of time is extremely rare.

When starting the engine, place the engine on the ground, hold it down with your foot, and pull the recoil starter with your hand.
From a safety point of view, it is particularly necessary for the starting rotation to be about idling rotation (for example, 3000 RPM) or less than the centrifugal clutch engagement rotation (for example, 3500 RPM) so that there is no danger of the cutting tool rotating.

As a carburetor starter for a normal 2-cycle engine, 2
For wheeled vehicles, the one-way type engine is widely used, and for stationary engine engines with centrifugal weight governors, the chalk pulp method is widely used, but second-class engine engines are used in extremely cold winters, so they are kept in a cold state. In order to achieve one rotation torque that can overcome the large engine friction torque at the time, an intake air amount larger than the fitting opening is used, and in this case, a rich mixture is used to suppress the increase in rotation so as not to exceed the clutch rotation. It is widely known that there is a setting (so-called Rinochikun). However, if there is no automatic return device, it is necessary to manually return the high-squeak device and choke-no-Q-lube device, which has the drawback of requiring frequent operations at startup.

In the case of the en-chin portable working machine of the present invention, as mentioned above, the temperature is relatively high in spring, summer, and fall, so the increase in the en-def friction torque during cold conditions is small (if the air-fuel mixture shifts to a rich mixture, the throttle opening will be less than the idle opening). It is possible to start even if the fuel is not in use, and there is no risk of clutch engagement or cutting tool rotation.Therefore, in the case of the present invention, the float chamber fuel is injected into the fuel nozzle by a manual pump installed below the fuel oil level. By raising the engine and ejecting part of it outside the nozzle, it is possible to start by sending a rich mixture to the engine engine with the fitting ring open during recoil operation, and there is also the advantage that there is no need to perform a return operation after starting. .Also, since the pump is operated under the oil level, there is no need for a check valve on the pump, allowing for an extremely simple and inexpensive bob/bob structure.

Another means of enriching the air-fuel mixture is a new tickler device that pushes a float from the outside to raise the fuel oil level, but it is difficult to confirm the degree of rise of the curved surface, and it causes pollution due to fuel seeping out from the vent hole and the outside surface of the carburetor. dirt, excessive engulfment due to excessive oil level rise,
There are also problems such as difficulty in starting, and there is a drawback that starting is not safe and reliable.

The drawing is a longitudinal sectional view of the main part of the present invention. 1 is the carburetor body,
2 penetrates the carburetor body 1] Re-1 ventu IJ-
13 is a fuel nozzle. 4 +t-i1 child chamber, 5 is fuel inlet, 6 is float valve, 71 is float, 8 (1 float valve 7,
This is the fuel 2111 surface formed by the float 7.

9 is a ventilation hole for the float chamber 40, and 10 is a contact surface of the float chamber 4. Reference numeral 11 denotes a starting fuel pressure pump according to the present invention, which is located below the fuel oil level 8 and can be integrated with the float chamber 4 depending on the mounting condition, or it can be a separate body as shown in the figure, and can be connected to the joint 12 at the bottom of the float chamber with flexibility as shown by the dotted line. It is also possible to communicate with a pipe. Reference numeral 13 denotes a pump having an elastic restoring force, and is fixed to the pressure pump 11 with a -1z kun. The ejection cylinder 15 of the pressure pump 11 is located opposite the lower end hole 14 of the fuel nozzle 3 .

The present invention is constructed in this manner. When starting the fuel pump 11 at ℃・ruσ), press the knob 13 to release the fuel inside the fuel nozzle/l. , injects downward from the lower terminal L14 of 3, inside the fuel nozzle 3 σ) /
(The 11irii car rises and a part of it is ejected onto the nozzle and flows out into the bench 1 and 2, forming a rich air-fuel mixture by refilling the engine, making it possible to start easily and reliably.

[Brief explanation of drawings]

The drawing is a longitudinal sectional view of the main part of the present invention. patent applicant Wall Lofer East Co., Ltd. direction

Claims (1)

[Claims] A starting device for a float-type carburetor for a portable working machine engine, which comprises a starting fuel pressure-feeding pump provided below the fuel oil level, with an ejection tube facing a lower end hole of a fuel nozzle.