JPS59190477A - Lift detecting device of fuel valve - Google Patents

Abstract

PURPOSE:To enable a valve lift to be easily detected for a fuel valve even if it is of complicated construction electronically and hydraulically controlled, by embedding a valve lift sensor in the vicinity of a point end part of the fuel valve. CONSTITUTION:A hydraulic piston 2, being built in the main unit 1 of a fuel valve and integrally forming a lift detecting part 5 in the part of a push rod 4 connected to a needle valve 3, is controlled by control oil supplied to an upper chamber 6 of the hydraulic piston. Then a coil 8 wound on a bobbin 7 is arranged in the periphery of the lift detecting part 5 as a sensor, cooperatively forming a differential transformer with the lift detecting part 5 to measure the movement of the hydraulic piston 2. Here the movement of the hydraulic piston 2, which performs the action almost equal to that of the needle valve 3, can be considered as the action of the needle valve 3. While a lead wire 10 is drawn out to the outside from a collecting hole 11 of leaking fuel oil through a lead wire guide hole 13. In such way, a lift of the fuel valve, even if it is of complicated construction, can be easily detected.

Description

[Detailed description of the invention] The present invention relates to a fuel valve lift detection device.

Conventionally, as shown in Fig. 1, a sensing pin led out from the top of the nozzle boulder (A) was attached to a push rod connected to a needle valve (A), and a sensing pin was placed at the tip of the sensing pin. Sensor +j (such as differential transformer or electromagnetic induction method)
C) was installed to measure the behavior of the needle valve (4) by positioning the tip of the sensing pin.

Modern fuel valves have complicated structures and are electronically controlled, so it is not possible to easily attach a nozzle boulder to move the needle valve (e) as shown in Figure 1. Detecting the injection timing is extremely difficult.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a fuel valve lift detection device in which a sensor is incorporated into the fuel valve so that the fuel valve lift can be easily detected. be.

In the present invention, a needle valve detection section is provided adjacent to the needle valve in the fuel valve and interlocks with the needle valve, and a bobbin with a coil completely wound around the lift detection section is placed around the lift detection section. The lift detection section and the coil are configured to form a differential transformer, and the behavior of the fuel valve is controlled by the Sentsu embedded near the tip of the fuel valve. Since it can be detected, valve lift can be easily detected even if the fuel valve has a complicated structure due to electro-hydraulic control.

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, a hydraulic piston (2) built into the fuel valve body (1) is connected to a push rod (4) connected to a needle valve (3).
A lift detection section (5) is integrally formed in the section.

It is controlled by control oil supplied to the upper chamber (6) of the hydraulic piston. There is a bobbin (7) around the lift detection part (5).
The coil wound around (8) is arranged as a sensor +7- and works together with the lift detection part (5) to form a differential transformer, which measures the movement of the hydraulic piston (2). Since the hydraulic piston (2) behaves almost the same as the needle valve (3), the movement of the hydraulic piston (2) can be regarded as the behavior of the needle valve (3).

The lead wire OQ of Koi IV (8) is connected to the fuel oil leak recovery hole (
11) is extracted to the outside by 1ffl. The fuel oil leak recovery hole aυ is a hole that guides the leaked fuel oil from the needle valve (3), and the leaked fuel oil is discharged to the outside from the screw plug receiving hole (6). Leak collection hole (1, 1)
The lead wire is led out through the lead hole. The lead wire guide hole Q4 is closed with an adhesive (14) or the like to prevent fuel oil from leaking therefrom.

Further, OQ is a fuel oil supply hole, and (B) is a nozzle chamber. High-pressure fuel oil guided into the nozzle chamber QQ pushes the needle valve (3) upward to perform fuel injection.

Furthermore, it is of course possible to measure the behavior of the needle valve (3) even if the injection valve 0η is replaced freely.

As described above, according to the present invention, since the behavior of the fuel valve is detected by a sensor embedded near the tip of the fuel valve, valve lift can be easily detected even if the fuel valve has a complicated structure due to electronic hydraulic control. can. 1. It is convenient because the guide hole for the coil lead wire to the outside can be shared with the fuel oil leak recovery hole of the fuel valve.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional example, and FIG. 2 is a sectional view showing an embodiment of the present invention. (1)...Fuel valve body, (2)...Hydraulic piston,
(3)...needle valve, (5)...lift detection section,
(7)...Bobbin, (8)...Coil, Lead wire, (I)...Fuel oil leak recovery hole agent
Yoshihiro Morimoto Figure 1 Figure 4 / Figure 2

Claims (1)

[Scope of Claims] 1. A needle valve detection section is provided in contact with the needle valve in the fuel valve and interlocks with the needle valve, and a hobbin with a coil wound around the lift detection section is connected to the lift detection section. 2. A fuel valve lift detection device, characterized in that the fuel valve lift detection device is provided by being fitted onto the outside so that the coil passes through, and the lift detection portion and the coil form a differential transformer. 2. Guide of the coil lead wire to the outside. 2. The fuel valve lift detection device W according to claim 1, wherein the hole is also used as a fuel oil leak recovery hole of the fuel valve.