JPS614860A - Injection-rate meter - Google Patents

Abstract

PURPOSE:To facilitate the installation and handling of the captioned apparatus with which fuel is jetted into a capacity chamber and the fuel injection rate is measured by obtaining the rate of variation of the pressure increase in the capacity chamber and the liberation and cut-off of fuel is controlled on the basis of the trigger pulses by use of a solenoid valve. CONSTITUTION:The inside of the capacity chamber 2 of a body 1 is filled with fuel in the initial state, and a solenoid valve 4 is in closed state. When fuel is jetted-out from a fuel injection valve 3, the fuel pressure in the capacity chamber 2 increases in accordance with the injection amount. A pressure pickup-up 5 detects said increase, and the rise of pressure is detected through the amplification by an amplifier 6, and the detected output is input into a microcomputer 12. While a trigger signal supplied from a trigger pulse generator 10 is input into a controller 11 and the microcomputer 12. Then, after a set time, the controller 11 opens the solenoid valve 4, and the fuel jetted into the capacity chamber 2 is linerated. When the solenoid valve 4 is opened, linberation occurs over the set pressure of a back-pressure adjusting valve 7, and an initial state is restored.

Description

[Detailed description of the invention] The present invention relates to an injection rate meter.

FIG. 1 shows the structure of a conventional injection rate measuring device.

In the figure, 01 is the injection rate needle body, 02 is the mounting hardware, 0
3 is a nozzle holder, 04 is a measuring tube, and 05 is a pressure measuring strain gauge. 22 The pressure value is measured by an amplifier (not shown). o6 is a needle valve, and 07 is a discharge pipe. The measuring tube o4 is set long enough so that its pressure wave does not return during the duration of the injection from the nozzle.

When a liquid is injected into a liquid-filled tube with a uniform cross-section, a pressure increase occurs depending on the amount injected. That is.

Δp=ρaV, ? == q/A・”・Δp−ρ
a-q/A, that is, Δ, a.

Here, Δp: Pressure rise k19/cm2ρ: Liquid density kg/an4・2 a: Sound velocity in liquid ~YuV2 Flow velocity in liquid q: Flow rate (Yn3/5ee A: Principle of pipe cross-sectional area crn2 This is an application of

To explain the measurement of the injection rate, ink is injected at high pressure from the tip of the nozzle o3 through the injection pipe from an injection pump (not shown). At this time, the measuring tube 04 is filled with fuel.9. Changes in flow velocity occur depending on the injected flow rate. This change in flow rate appears as a change in pressure within the pipe. By detecting this with a pressure measuring strain cage, the injection rate on the open side during injection can be measured.

Here, the action of the needle valve 06 is to send the same amount as the injection amount to the discharge pipe 0.
7, and if it is narrowed too much, the amount of discharge will be small, and if the pressure in the measuring tube 04 is too high, the injection rate will not be accurate.

In addition, if the diaphragm is expanded too much, the amount of emission will be large.Measurement tube 04
This creates a cavity within the cylinder, which also prevents the injection rate from being accurate.

In order to accurately measure the injection rate with the above, it is necessary to adjust the throttle of the needle valve appropriately, and this adjustment requires a great deal of skill. In addition, the nozzle mounting portion and the measuring tube must be precisely uniform without any change in cross section, and are very expensive, and their installation and handling are also very troublesome.

The purpose of the present invention is to focus on the above-mentioned points, and to provide an injection refill that is easy to install and handle, and is inexpensive to manufacture. A device that injects liquid into a container.

A pressure gauge that measures the pressure inside the container, a device that discharges the liquid in the container using a solenoid valve, and a device that generates a reference trigger pulse of one pulse per revolution of the fuel pump camshaft.
It consists of a controller for the electromagnetic valve to which the trigger pulse signal of the device is input, and a computer to which the output signal of the pressure gauge and the trigger pulse signal are input and calculates the injection rate.

In this case, instead of determining the injection rate from the pressure rise due to a change in flow velocity in a conventional uniform pipe, the injection rate is determined by injecting fuel into a uniform volume and determining the rate of change in the pressure rise within the volume chamber. We are trying to measure the rate.

The present invention can be applied to any device that measures momentary changes in the flow rate of liquid that is intermittently discharged.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory diagram showing an injection rate measuring device according to an embodiment of the present invention. - In the figure, 1 is a main body, inside which is a volume chamber 2.

3 is a fuel injection valve, 4 is a solenoid valve, 5 is a pressure pipe,
6 is a pressure signal amplifier. 7 is the back pressure regulating valve body, 8
is a valve, and 9 is a spring.

10 is a trigger nozzle generator synchronized with the rotation angle of a fuel pump camshaft (not shown); 11 is a controller for the solenoid valve 4; and 12 is a microcomputer.

Its components are shown in FIG. Clock signal generator, A74) converter, injection rate calculator (dq/
dt), a D//A converter, a rotation angle calculator, an injection rate calculator (dq/dθ), and a D/A converter. Of these, the clock signal generator, A/D converter, injection rate calculator (dq/dt), and D/A converter are the basic components, and the following items are added as necessary and are further enclosed by broken lines in the figure. It is indicated by the reference numeral 120.

The operation in the case of the above configuration will be described.

First, in the initial state, the volume chamber 2 is filled with fuel and the solenoid valve 4 is in a closed state. At this time, when fuel is discharged due to the rotation of a fuel pump (not shown), fuel is injected from the fuel injection valve 3. Then, the pressure of the fuel within the volume chamber 2 increases in proportion to the injected amount. Detecting this with pressure pizzazzi 5 and amplifying it with Anzoro, the third
As shown in Figure (C), the pressure increase can be detected at the same time as injection. This output signal is input to the microcomputer 12. Further, the trigger pulse generator 10 generates a reference trigger pulse of 1 pulse per revolution. This trigger signal is input to the solenoid valve controller 11 and microcomputer 12.

The solenoid valve controller opens the solenoid valve 4 after a time of Δt1 set from the reference signal, releases the fuel injected into the volume chamber 2, and further opens the solenoid valve for a time of Δt2. When the solenoid valve 4 opens, discharge occurs when the pressure exceeds the set pressure of the back pressure regulating valve 7, and the initial state is returned again.

The operation of the microcomputer will be explained with reference to FIG.

The pressure signal from the amplifier (pressure signal amplifier 7') 6 is converted into a digital value every minute by a clock signal generator installed in the computer (A/D converter).
. The successive changes in this value are determined (injection rate calculation unit), which is then subjected to D/A conversion and the injection rate (ciq,
/at g3/see) is output.

The part indicated by reference numeral 120 indicates the injection rate (dq/
dθ mm'/deg
The injection rate calculator converts t into dq/dθ).

It is shamefully converted and output.

The above case has the following effects.

As described above, since fuel is discharged and closed by the electromagnetic valve, there is no need to adjust the needle valve's throttle, which is a tedious task, and the handling becomes very simple. It also has fewer high-precision parts and is inexpensive to manufacture.

Furthermore, since the injection rate is immediately output by the microcomputer, it is effective in elucidating injection phenomena.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a conventional injection rate needle, Fig. 2 is an explanatory diagram showing an injection rate measuring device according to an embodiment of the present invention, and Fig. 3 is an explanatory diagram showing a signal when the device in Fig. 2 is activated. , clock signal,
A diagram showing the volume chamber pressure, injection rate, needle valve lift, and injection pressure, and FIG. 4 is an explanatory diagram showing the operation of configuration 2 of the microcomputer. 2... Volume chamber, 3... Fuel injection valve, 4... Solenoid valve, 5... Pressure kick-up, 10... Trigger pulse generator, 11... Solenoid valve controller, 12...・
microcomputer. Oγ ″A=1 old

Claims (1)

[Claims] 1. A container filled with liquid, a device to inject liquid into the container, a pressure gauge to measure the pressure in the container, a device to discharge the liquid in the container using a solenoid valve, and one part of the fuel pump camshaft. A device that generates a reference trigger pulse of one pulse per rotation, a controller for the solenoid valve to which the trigger pulse signal of the device is input, and an output signal of the pressure gauge and the trigger pulse signal are input to calculate the injection rate. An injection rate meter comprising a computer.