JPS5937250A - Fuel injection quantity controlling type acceleration pump - Google Patents

Abstract

PURPOSE:To render the fuel consumption economical and reasonable, by controlling the fuel injection quantity automatically over a wide range of engine operation from rapid increase of the output to slow increase of the same by imparting an acceleration pump with a function capable of metering the quantity of fuel to be supplied corresponding to the speed of operation of an output control means. CONSTITUTION:A small hole 3 is formed to communicate with an acceleration pump. At the time of rapid increasing of the output, pressure of fuel in a pump chamber 2 is increased by the rapid downward movement of a pump plunger 1, so that part of the fuel flows back into a fuel supply passage 6 through the small hole 3. However, since the hole 3 is so small, the resistance to the fuel flow through the hole 3 is fairly great, so that most of fuel is ejected into a carburetor by forcing a discharge valve 4 open. At the time of slow increasing of the output, on the other hand, the quantity of fuel passed through the small hole 3 is increased relatively while the quantity of fuel ejected from a nozzle 7 of the acceleration pump is decreased. Thus, the quantity of fuel ejected from the acceleration pump can be controlled automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an improvement of a carburetor acceleration pump that has been conventionally used in internal combustion engines used in automobiles and the like.

Conventionally, carburetor internal combustion engines used in automobiles etc. are subject to sudden load fluctuations, and various measures have been taken to be able to adequately respond to these load fluctuations. In a carburetor-type internal combustion engine, which is the driving force, when the output is rapidly increased, it is impossible to meet the demand with the carburetor alone, so a carburetor with an accelerator pump is adopted to meet this demand. meets the requirements.

However, these conventionally used accelerator pumps for carburetors with accelerator pumps are used only when a sudden increase in output is not desired, such as when gradually increasing output or when controlling output in small increments during speed adjustment. In some cases, the output adjustment device does not require an increase in fuel, but the output adjustment device and the acceleration pump are mechanically connected, so the output adjustment device increases the output even slightly, regardless of whether the internal combustion engine requires it or not. If the engine moves in that direction, fuel proportional to the amount of movement is measured and supplied to the internal combustion engine, which increases the amount of fuel used and is uneconomical.

The present invention improves this drawback by supplying a necessary and sufficient amount of fuel when the output increases rapidly, and less when the output increases gradually, and also supplies a sufficient amount of fuel when the output increases gradually or when the output device operates in small steps. In order to prevent fuel from being supplied from the accelerator pump nozzle at times, it was equipped with a function that measured the amount of fuel supplied in accordance with the operating speed of the output adjustment device.

This is a rational and economical accelerator pump for carburetor internal combustion engines.

To explain the operation using the diagram, the difference from conventional accelerator pumps is that a small hole for communication is provided. As a result, if there is a request for a sudden increase in output, the pump plunger (■) will rapidly descend, causing the pressure of the fuel in the pump chamber (■) to rise, and some of the fuel will be absorbed into the small hole for communication (■). The fuel passes through the pump chamber (■) and is injected into the fuel supply path (■), but since the small communication hole (■) is small, there is a large resistance to the passage of the fuel, and most of the fuel pressurized in the pump chamber (■) flows through the discharge valve (■). is forced open and squirted into the carburetor, rapidly increasing the output of the internal combustion engine.

Next, when the output gradually increases, the pump plunger (■) slowly descends, so the amount of fuel passing through the small communication hole (■) is smaller than the amount of fuel passing through the discharge valve (■). , becomes relatively large, and the amount of fuel ejected from the accelerator pump nozzle (①) decreases. Also, when the output increases very slowly, the fuel passes through the small communication hole (■), so no fuel passes through the discharge valve (■), and no fuel is ejected from the accelerator pump nozzle (■). .

In this way, it is an ideal accelerator pump for carburetor-type internal combustion engines that automatically controls the amount of fuel injection from a sudden increase in output to a very gradual increase in output. Furthermore, by installing a device that variably adjusts the passage of the small hole for communication of the acceleration pump, more general adjustment on the engine side can be made possible.

[Brief explanation of drawings]

The figure is a diagram of the principle of the present invention. ■Pump plunger ■Pump chamber ■Small hole for communication ■Discharge valve

Claims (1)

[Claims] It is attached to the carburetor of a carburetor-type internal combustion engine to compensate for a temporary fuel shortage when the engine suddenly accelerates. A communication port that communicates the pump chamber of the acceleration pump with a supply side that supplies fuel to the acceleration pump, and the flow rate of fuel passing through the communication port can be adjusted or shut off as necessary. An accelerator pump that can control the injection amount by adding a function.