JPH0542668U - Cooled fuel injection nozzle - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a fuel injection nozzle that does not need to be provided with a cooling oil pipe or a circulation pump outside the fuel injection nozzle with high supercharging and high output. A cavity is provided inside a main body 3 of a fuel injection nozzle, and a working fluid is enclosed in the cavity 4 to form a heat pipe. The working fluid evaporates at a high temperature portion on the seat surface side of the needle valve 2. However, the needle valve seat surface is cooled by condensing in the low temperature portion on the fuel oil passage 6 side.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fuel injection nozzle for an internal combustion engine.

[0002]

[Prior Art]

 FIG. 4 shows a conventional cooling type fuel injection nozzle. The injection nozzle is composed of a needle valve 2 and a main body 13, and a fuel passage 15 and a cooling oil circulation passage 14 are arranged in the main body. It is configured to cool the seat surface of the needle valve 2 of the injection nozzle 11.

[0003]

[Problems to be solved by the device]

 However, in the conventional cooling type fuel injection nozzle, since it is necessary to circulate the cooling oil from the outside of the fuel injection nozzle, it is necessary to provide a cooling oil pipe and a cooling oil circulation pump outside, and the overall structure is complicated. There was a drawback.

An object of the present invention is to solve the above problems of the conventional device, and to cool the fuel injection nozzle, a fuel injection nozzle which does not need to be provided with a cooling oil pipe or a circulation pump outside the fuel injection nozzle. To provide.

[0005]

[Means for Solving the Problems]

 The cooling type fuel injection nozzle of the present invention comprises a needle valve and a main body, wherein a cavity 4 other than the fuel passage provided inside the main body and a seat surface side of the needle valve 2 enclosed in the cavity. It is characterized in that it has a working fluid that evaporates in the high temperature part and condenses in the low temperature part on the side of the fuel oil passage 6 and that functions as a heat pipe.

[0006]

[Action]

 With the above configuration, the working fluid evaporates at the temperature of the seat surface side of the needle valve 2, moves in the cavity 4 provided in the main body 3, and condenses at the temperature of the fuel passage 6 side. By this action, the working fluid selects heat from the seat surface side of the needle valve 2 to the fuel passage 6 side, so that the seat surface side of the needle valve 2 is cooled. Therefore, even in a highly supercharged diesel engine, the fuel injection nozzle There is no risk of seizure.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. 1 is a vertical sectional view of a fuel injection nozzle of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view of an internal combustion engine showing the periphery of the fuel injection nozzle. The fuel injection nozzle 1 is composed of a needle valve 2 and a main body 3. The main body 3 has a main body 3a fitted to the outside of the main body 3b, and a cavity 4 is provided between the main body 3b and the main body 3a. A working fluid is enclosed in the cavity 4 and functions as a heat pipe. A fuel passage 5 is provided in the main body 3b as shown in FIGS. 1 and 2, and a fuel passage 6 for cooling the working fluid is provided at the inlet of the fuel passage 5.

Next, the operation of the above embodiment will be described. When the internal combustion engine is operated, the seat surface side of the needle valve 2 is heated by the high temperature of the combustion gas in the cylinder, and the heat causes the working fluid on the needle valve seat side in the cavity 4 to evaporate and move in the cavity, and the main body 3b The fuel is cooled by the fuel flowing through the fuel passages 5 and 6 provided in the fuel cell, condensed, and drops downward. As a result, heat is transferred from the seat surface side of the needle valve 2 to the fuel passage 6 side of the main body 3, and the seat surface side of the needle valve 2 is cooled.

[0009]

[Effect of the device]

 Since the present invention is configured as described above, the working fluid enclosed in the cavity is heated and evaporated on the side of the needle valve seat, condensed on the side of the fuel passage 6 on the low temperature side, and repeated to repeat the fuel injection. Since the nozzle is sufficiently cooled, it is not necessary to install a cooling oil pipe or circulation pump outside the combustion injection nozzle.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a fuel nozzle according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view of the internal combustion engine showing the vicinity of the fuel injection nozzle.

FIG. 4 FIG. 1 corresponding diagram of the conventional example

[Explanation of symbols]

1 ... Fuel injection nozzle, 2 ... Needle valve, 3 ... Main body (3a and 3b)
4) Cavity, 5, 6 ... Fuel passage.

Claims (1)

[Scope of utility model registration request] 1. A fuel injection nozzle for an internal combustion engine comprising a needle valve and a main body, wherein a cavity (4) other than the fuel passage provided inside the main body; and a needle valve (2) enclosed in the cavity. Of the cooling type fuel injection nozzle, which has a working fluid that functions as a heat pipe by evaporating in the high temperature portion on the seat surface side and condensing in the low temperature portion on the fuel oil passage (6) side.