Patent Description:
Generally, an injector of a diesel engine may inject a fuel into a combustion chamber using a pressure difference between an upper end and a lower end in a needle by a control valve. The needle may be arranged in a high-pressure passage in the injector. The control valve may be arranged in a low-pressure passage in the injector.

According to related arts, particles caused by a degeneration of the fuel may be continuously stagnated between the control valve and the low-pressure passage. The particles may be accumulated on an inner wall of the low-pressure passage to generate a malfunction of the control valve. <CIT> describes an internal combustion engine comprising a plurality of cylinders and an injection system. <CIT> describes a method for operating an injection system. <CIT> describes a method for verifying operation of a fuel injector.

Example embodiments provide a method of removing particles in an injector of a diesel engine that may be capable of effectively removing the particles accumulated in a low-pressure passage.

Example embodiments also provide an apparatus for performing the above-mentioned method.

Example embodiments still also provide a diesel engine including the above-mentioned apparatus.

According to the invention, there is provided a method of removing particles in an injector of a diesel engine. In the method of removing the particles in the injector of the diesel engine, a stop of the diesel engine is recognized. An injection signal is inputted into the injector of the stopped diesel engine. A control valve of the injector is moved in a low-pressure passage by the injection signal to remove the particles accumulated on an inner wall of the low-pressure passage.

According to the invention, the method further includes checking a non-input of a cranking signal to the diesel engine from a stop point of the diesel engine to a set time.

According to the invention, inputting the injection signal to the injector includes inputting the injection signal to the injector for a set time by a set period.

In example embodiments, inputting the injection signal to the injector may include inputting the injection signal to a plurality of the injectors in cylinders of the diesel engine.

According to the invention, the method further includes stopping the removal of the particles in the injector of the diesel engine when a cranking signal may be checked in removing the particles.

According to the invention, there is provided an apparatus for removing particles in an injector of a diesel engine. The apparatus includes a controller and a control valve. The controller recognizes a stop of the diesel engine. The controller inputs an injection signal into the injector of the stopped diesel engine. The control valve is moved in a low-pressure passage of the injector by the injection signal to remove the particles accumulated on an inner wall of the low-pressure passage.

According to the invention, the controller further checks a non-input of a cranking signal to the diesel engine from a stop point of the diesel engine to a set time.

According to the invention, the controller inputs the injection signal to the injector for a set time by a set period.

In example embodiments, the controller may input the injection signal to a plurality of the injectors in cylinders of the diesel engine.

According to the invention, the controller further stops the removal of the particles in the injector of the diesel engine when a cranking signal may be checked in removing the particles.

According to the invention, there is provided a diesel engine. The diesel engine includes a controller and a particle-removing apparatus. The controller checks a stop of the diesel engine. The controller inputs an injection signal into the injector of the stopped diesel engine. The particle-removing apparatus includes a control valve. The control valve is moved in a low-pressure passage of the injector by the injection signal to remove the particles accumulated on an inner wall of the low-pressure passage.

According to example embodiments, when the diesel engine may be stopped, a gap between the control valve and the low-pressure passage may be narrower than a gap when the diesel engine may be operated. When the injection signal may be inputted to the injector, the control valve may be moved in the low-pressure passage to remove the particles accumulated on the inner wall of the low-pressure passage. Thus, a malfunction of the control valve caused by the particles may be previously prevented.

Example embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings. <FIG> represent non-limiting, example embodiments as described herein.

Various example embodiments will be described more fully hereinafter with reference to the accompanying drawings, in which some example embodiments are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity.

It will be understood that when an element or layer is referred to as being "on," "connected to" or "coupled to" another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present.

It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention.

Example embodiments are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized example embodiments (and intermediate structures). Thus, example embodiments should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an implanted region illustrated as a rectangle will, typically, have rounded or curved features and/or a gradient of implant concentration at its edges rather than a binary change from implanted to non-implanted region. Likewise, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation takes place. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the present invention.

Hereinafter, example embodiments will be explained in detail with reference to the accompanying drawings.

<FIG> is a cross-sectional view illustrating an injector of a diesel engine with a particle-removing apparatus in accordance with example embodiments and <FIG> are cross-sectional views illustrating operations of the particle-removing apparatus in <FIG>.

Referring to <FIG>, an injector of a diesel engine E may include an injector body <NUM>, a needle <NUM>, a spring <NUM>, a control valve <NUM> and an electromagnet solenoid <NUM>.

The injector body <NUM> may include a fuel chamber <NUM>, an injecting hole <NUM>, a high-pressure passage <NUM> and a low-pressure passage <NUM>. The fuel chamber <NUM> may be formed in the injector body <NUM> to receive a fuel. The injecting hole <NUM> may be extended from the fuel chamber <NUM>. The injecting hole <NUM> may be formed through a lower end of the injector body <NUM> oriented toward a combustion chamber. The fuel in the fuel chamber <NUM> may be injected to the combustion chamber through the injecting hole <NUM>. The high-pressure passage <NUM> may be connected to an upper portion of a side surface of the fuel chamber <NUM>. The low-pressure passage <NUM> may be connected to an upper surface of the fuel chamber <NUM>.

The needle <NUM> may be movably received in the fuel chamber <NUM> along a vertical direction. The needle <NUM> may be moved in the vertical direction by a pressure difference between an upper space and a lower space in the fuel chamber <NUM> to selectively open and close the injecting hole <NUM>.

The spring <NUM> may be arranged in the upper space of the fuel chamber <NUM> over the needle <NUM> to resiliently support the needle in a downward direction, i.e., toward the injecting hole <NUM>. When a pressure of the fuel supplied through the high-pressure passage <NUM> may be higher than a tensile force of the spring <NUM>, the needle <NUM> may be upwardly moved with compression of the spring <NUM> so that the injecting hole <NUM> may be opened.

The control valve <NUM> may be movably arranged in the low-pressure passage <NUM> in the vertical direction. The control valve <NUM> may control flows of the fuel from the high-pressure passage <NUM> to the low-pressure passage <NUM> by a control of the electromagnet solenoid <NUM>. When the electromagnet solenoid <NUM> may receive an injection signal, the control valve <NUM> blocking the low-pressure passage <NUM> may be upwardly moved so that the low-pressure passage <NUM> may be opened. That is, the pressure difference may be generated between the upper space and the lower space in the fuel chamber <NUM> centering around the needle <NUM>. Thus, the fuel in the fuel chamber <NUM> may flow through the low-pressure passage <NUM> so that the needle <NUM> may be upwardly moved with the compression of the spring <NUM>. As a result, the injecting hole <NUM> may be opened to inject the fuel into the combustion chamber through the injecting hole <NUM>. The control valve <NUM> may be continuously moved in the low-pressure passage <NUM> along the vertical direction during the diesel engine E may be operated.

Referring to <FIG>, during the diesel engine E may be operated, a degenerated fuel and/or particles P may be accumulated on an inner wall of the low-pressure passage <NUM>. During the diesel engine E may be stopped, a gap D between the control valve <NUM> and the low-pressure passage <NUM> may be uniformly maintained. In contrast, during the diesel engine E may be operated, a gap D1 between the control valve <NUM> and the low-pressure passage <NUM> may be wider than the gap D due to the fuel having a high pressure in the injector.

Therefore, during the diesel engine E may be operated, the continuously moved control valve <NUM> may not remove the particles accumulated on the inner wall of the low-pressure passage <NUM> due to the wide gap D1. As a result, the particles P may be continuously accumulated on the inner wall of the low-pressure passage <NUM> to hinder the vertical movement of the control valve <NUM>.

In order to prevent the above-mentioned problem, a particle-removing apparatus may be provided to the injector. The particle-removing apparatus may include a controller <NUM> and the control valve <NUM>.

The controller <NUM> may recognize the stop of the diesel engine E. Further, the controller <NUM> may check an input of a cranking signal into the diesel engine E from a stop point of the diesel engine E to a set point.

When the cranking signal may not be inputted into the diesel engine E from the stop point to the set point, the controller <NUM> may transmit an injection signal to the injector. The controller <NUM> may input the injection signal into the injectors of cylinders in the diesel engine E. Particularly, the controller <NUM> may input the injection signal into the injector for a set time by a set period.

The electromagnet solenoid of the injector may operate the control valve <NUM> by the injection signal of the controller <NUM>. As mentioned above, during the diesel engine E may be stopped, because the gap D between the control valve <NUM> and the low-pressure passage <NUM> may be narrower than the gap D1, the control valve <NUM> may be vertically moved in the low-pressure passage <NUM> to remove the particles P on the inner wall of the low-pressure passage <NUM>. Particularly, the removal of the particles P may be performed by the control valve <NUM> of the injector without using an additional part.

In contrast, when the cranking signal may be inputted into the diesel engine E during the stop point of the diesel engine E to the set time, the controller <NUM> may not transmit the injection signal to the injector. Thus, the controller <NUM> may not input the injection signal into the injectors of the cylinders in the diesel engine E to stop the removal of the particles P.

<FIG> is a flow chart illustrating a method of removing particles in the injector using the apparatus in <FIG>.

Referring to <FIG> to <NUM>, in step ST210, the controller <NUM> may recognize the stop of the diesel engine E. For example, the controller <NUM> may recognize an off of an ignition key of the diesel engine E to recognize the stop of the diesel engine E.

In step ST220, the controller <NUM> may check the input of the cranking signal into the diesel engine E from the stop point of the diesel engine E to the set point. The set time may be determined by a user in accordance with kinds, conditions, etc., of the diesel engine E.

When the cranking signal may not be inputted into the diesel engine E from the stop point to the set point, in step ST230, the controller <NUM> may transmit the injection signal to the injector. The controller <NUM> may input the injection signal into the injectors of the cylinders in the diesel engine E. Particularly, the controller <NUM> may input the injection signal into the injector for the set time by the set period.

In step ST240, the electromagnet solenoid of the injector may operate the control valve <NUM> by the injection signal of the controller <NUM>. During the diesel engine E may be stopped, because the gap D between the control valve <NUM> and the low-pressure passage <NUM> may be narrower than the gap D1, an outer surface of the control valve <NUM> may be positioned adjacent to the inner wall of the low-pressure passage <NUM>. Thus, the control valve <NUM> may be vertically moved in the low-pressure passage <NUM> to remove the particles P on the inner wall of the low-pressure passage <NUM>. Particularly, the removal of the particles P may be performed by the control valve <NUM> of the injector without using an additional part.

Claim 1:
A method of removing particles (P) in an injector of a diesel engine (E) including an injector body (<NUM>) and a control valve (<NUM>), wherein the injector body (<NUM>) includes a high-pressure passage (<NUM>) and a low-pressure passage (<NUM>), wherein the control valve (<NUM>) is movably arranged in the low-pressure passage (<NUM>) for controlling flows of a fuel from the high-pressure passage (<NUM>) to the low-pressure passage (<NUM>) such that an outer surface of the control valve (<NUM>) is positioned adjacent to an inner wall of the low-pressure passage (<NUM>) and, when an injection signal is received, the control valve (<NUM>) blocking the low-pressure passage (<NUM>) is moved so that the low-pressure passage (<NUM>) is opened, the method comprising:
recognizing a stop of the diesel engine (E);
recognizing a non-input of a cranking signal to the diesel engine (E) from a stop point of the diesel engine (E) to a set time;
inputting an injection signal to the injector of the stopped diesel engine (E);
moving the control valve (<NUM>) of the injector adjacently to the inner wall of the low-pressure passage (<NUM>) in a low-pressure passage (<NUM>) by the injection signal to remove the particles (P) accumulated on the inner wall of the low-pressure passage (<NUM>),
wherein the injection signal to the injector is inputted for a set time by a set period; and
when a cranking signal is inputted into the diesel engine (E) during removing the particles (P), stopping the removal of the particles (P).