Fuel injection device

Abstract

A fuel injection device (100) includes a control body (40) which is provided with an injection port (44), a nozzle needle (60) which opens or closes the injection port (44), a pressure control chamber (53) for controlling a movement of the nozzle needle (60), an inlet channel (52) through which high-pressure fuel is introduced into the pressure control chamber (53), an outlet channel (54) through which the fuel is discharged from the pressure control chamber (53), and a floating plate (70) which opens or closes the inlet channel (52).In the fuel injection device (100), the control body (40) includes a cylinder (56) which defines the pressure control chamber (53) in the radial direction, and an inner wall section (56a) of the cylinder (56) includes a connecting groove (57a) which connects an inlet chamber (53a) provided in the pressure control chamber (53) on one side of the inlet channel (52) with respect to the floating plate (70), with a back pressure chamber (53b) provided in the pressure control chamber (53) on one side of the nozzle needle (60) with respect to the floating plate (70).

Description

CROSS-REFERENCE TO RELATING REGISTRATION

[0001] The application is based on the Japanese patent application JP 2010-080838 A, filed on March 31, 2010, and JP 2010-270647 A, filed on December 3, 2010, the disclosures of which are hereby incorporated by reference. TECHNICAL AREA

[0002] The present invention relates to a fuel injection device that injects high-pressure fuel into a combustion chamber of an internal combustion engine. BACKGROUND OF THE INVENTION

[0003] A fuel injection device is known, including a valve body having a high-pressure passage and a pressure control chamber therein, and a valve element for opening / closing an injection port in response to axial movement of the valve body within the body. The valve element movement is controlled by fuel pressure in the pressure control chamber. For example, Patent Document 1, as an example of the fuel injection device, teaches a method for the fuel injection device with a control element that is displaceable or movable axially within the pressure control chamber and opens or closes an inlet channel. When the control element closes the inlet channel, it prevents high-pressure fuel from flowing into the pressure control chamber. The fuel pressure in the pressure control chamber is rapidly increased by the operation of the control element.Thus, the valve element, which is controlled by the fuel pressure in the pressure control chamber, can quickly open the injection port. State of the art documentation

[0004] [Patent document 1] EP 1656498 A1

[0005] In the fuel injection device disclosed in patent document 1, the pressure control chamber can be divided by the control element located therein. To prevent a deterioration of pressure recovery in a back-pressure chamber, which is located on the valve element side with respect to the control element in the pressure control chamber, a passage must be provided for the fuel flowing from an inlet chamber, which is located on the inlet channel side with respect to the control element in the pressure control chamber, to the back-pressure chamber. Therefore, a gap through which the fuel can flow can be provided between an inner wall surface section, which defines the pressure control chamber, and an outer wall surface section, which is one of the control elements and is opposite the inner wall surface section.

[0006] However, if the gap between the inner wall surface section defining the pressure control chamber and the wall surface section of the control element is enlarged to create a sufficient channel area for fuel flow, the control element may tilt relative to the axial direction of the valve body. Consequently, with respect to the tilted control element, it may be difficult for it to move smoothly within the pressure control chamber, potentially leading to wear and tear on the opening of the pressure control chamber's inlet channel. This could restrict fuel flow into the pressure control chamber.

[0007] If the gap between the inner wall surface section defining the pressure control chamber and the wall surface section of the control element is narrowed to limit the tilt or deflection of the control element, pressure recovery in the back pressure chamber may take longer. Conversely, if the gap between the inner wall surface section defining the pressure control chamber and the control element is increased for faster pressure recovery in the back pressure chamber, the flow of high-pressure fuel into the inlet chamber is restricted, making it difficult to improve pressure recovery in the back pressure chamber. Consequently, it may be difficult to improve the response or responsiveness of the valve element when the valve is closed. SUMMARY OF THE INVENTION

[0008] In view of the above and further problems, it is an object of the present invention to provide a fuel injection device which improves the response or reaction capability of the valve element at the time of valve closure.

[0009] According to an example of the present invention, a fuel injection device comprises a valve body in which a high-pressure fuel passage is provided, and which has an injection opening at a tip end ora nozzle from which the high-pressure fuel is injected into a combustion chamber of an internal combustion engine; a valve element which is axially movable inside the valve body and opens or closes the injection port; a pressure control chamber which is provided in the valve body on one side opposite the injection port with respect to the valve element and which introduces the high-pressure fuel and controls the movement of the valve element by the fuel pressure; an inlet channel through which the high-pressure fuel is introduced into the pressure control chamber; an outlet channel through which the fuel is discharged from the pressure control chamber to an external low-pressure side; and a control element which is axially movable inside the pressure control chamber and opens or closes the inlet channel.In the fuel injection device, the valve body includes a cylindrical inner wall section that defines the pressure control chamber in its radial direction, and the cylindrical inner wall section includes a connecting groove or channel that connects an inlet chamber, which is provided in the pressure control chamber on one side of the inlet channel with respect to the control element, with a back pressure chamber, which is provided in the pressure control chamber on one side of the valve element with respect to the control element.

[0010] According to the preceding aspect of the present invention, the fuel introduced into the inlet chamber, which is located in the pressure control chamber on the side of the inlet channel relative to the control element, flows through the connecting groove provided on the cylindrical inner wall section into the back pressure chamber, which is located in the pressure control chamber on the side of the valve element relative to the control element. Therefore, a sufficient channel area or cross-section for the fuel flow from the inlet chamber to the back pressure chamber is ensured, thus preventing the pressure recovery in the back pressure chamber from being interrupted by the control element.

[0011] Furthermore, by providing a connecting groove, the gap between the cylindrical inner wall section and a wall section of the control element, which is radially opposite to the cylindrical inner wall section, can be reduced due to the suitable channel area or cross-section. Reducing this gap limits the tilting of the control element's axis relative to the axial direction of the valve body. This allows the control element to move smoothly within the pressure control chamber, enabling rapid opening of the inlet port to the pressure control chamber. This prevents the control element from restricting fuel intake into the pressure control chamber.

[0012] Thus, when the control element opens the intake port, the fuel is quickly introduced into the intake chamber, and the fuel can also flow easily into the back pressure chamber. This reduces the time required for pressure recovery before the valve element begins to move, thereby improving the response or responsiveness of the valve element during the valve closing start time of the fuel injection system.

[0013] For example, the cylindrical inner wall section can be provided with a movable contact surface that slidably contacts an outer circumferential wall section about the displacement axis of the control element. Thus, the sufficient channel area required for communication between the inlet chamber and the back-pressure chamber is ensured by the provision of the connecting groove. This prevents the pressure recovery in the back-pressure chamber from being disturbed by the control element, even if the movable contact surface, which slidably contacts or touches the outer circumferential wall section about the displacement axis of the control element, is located on the cylindrical inner wall section. Furthermore, the sliding and reciprocating motion of the control element on the movable contact surface can precisely limit the inclination of the control element's axis.Thus, the control element in the pressure control chamber can be shifted and moved back and forth with such precision that a high-pressure fuel injection into the intake port can be carried out without interference. Therefore, the time required for pressure recovery in the back pressure chamber is reduced so precisely that the responsiveness of the valve element during valve closure can be effectively improved.

[0014] Furthermore, the cylindrical inner wall section can be provided with a connecting wall surface that defines a connecting gap between the cylindrical inner wall section and an outer circumferential wall about a displacement axis of the control element, and the connecting gap connects the inlet chamber to the back pressure chamber.

[0015] Thus, the sufficient or appropriate channel area can be ensured by providing the connecting groove, so that the channel area defined by the connecting gap does not need to be enlarged. Therefore, the size of the connecting gap can be reduced to decrease the inclination of the control element's axis. Even if the channel area of ​​the connecting gap is small, as described above, forming the connecting gap results in an increase in the overall area of ​​the passage connecting the inlet chamber to the back pressure chamber. This reduces the time required for pressure recovery in the back pressure chamber, thereby improving the response or responsiveness of the valve element during valve closure.

[0016] Furthermore, the cross-section of the bottom section of the connecting groove can be arc-shaped in the radial direction. In this case, high pressure is applied to the connecting groove through which the high-pressure fuel flows. Since the bottom section of the connecting groove is arc-shaped, no excessive forces occur on the cylindrical inner wall section near the bottom section of the connecting groove. Thus, the provision of the connecting groove prevents wear on the cylindrical inner wall section. This improves the response or reaction time of the valve element at the valve closing time in the fuel injection device, thereby increasing the service life of the fuel injection device.

[0017] Furthermore, multiple connecting grooves can be arranged on the cylindrical inner wall section and offset from one another in the circumferential direction of the cylindrical inner wall section. In this case, the channel area of ​​the passage through which the fuel flows from the inlet chamber to the back pressure chamber can be easily enlarged. This allows a large quantity of fuel to flow into the back pressure chamber, so that pressure recovery in the back pressure chamber is achieved quickly. Therefore, the responsiveness of the fuel injection device at a valve closing time can be improved as desired.

[0018] Furthermore, the connecting grooves can be uniformly spaced circumferentially. In this case, the fuel flow around the control element becomes uniform. This limits the control element's tilt. Arranging multiple connecting grooves results in an increase in the fuel flow rate into the backpressure chamber. Furthermore, the uniform fuel flow is achieved by arranging the connecting grooves at equal intervals, allowing the pressure in the backpressure chamber to recover quickly and without change. Thus, the valve element's movement start time can be advanced, and time variation can be reduced. Therefore, the valve element's response time to valve closure in the fuel injection device can be improved and stabilized.

[0019] Furthermore, the valve body can be provided with a restraint section which faces a surface of the control element on one side of the backpressure chamber and restricts displacement of the control element by contacting its end surface during a displacement in the direction of disengagement from the inlet channel. The restraint section can also be provided with a sub-connecting groove which, together with the connecting groove, connects the inlet chamber to the backpressure chamber.

[0020] Thus, the arrangement of the restriction section, which limits the displacement of the control element by contacting the control element end face located on the side of the back pressure chamber, results in the restriction of the control element displacement in the direction of release from the intake port. Therefore, the displacement of the control element is limited by the restriction section. As a result, at the moment the valve element closes, the control element quickly closes the intake port and stops the introduction of high-pressure fuel into the pressure control chamber.

[0021] Furthermore, the sub-connecting groove, which connects the inlet chamber to the back-pressure chamber along with the connecting groove, is provided in the restriction section. Therefore, the fuel flow from the inlet chamber to the back-pressure chamber can be ensured in such a way that the pressure recovery in the back-pressure chamber is prevented from being interrupted by contact between the end face and the restriction section. Thus, the responsiveness of the valve element can be improved both at the valve closing and valve opening times in the fuel injection device.

[0022] Furthermore, the constraint section can be configured in a stepped shape that extends radially inwards with respect to the cylindrical inner wall section, so that the constraint section can precisely limit the displacement of the control element while keeping the design simple.

[0023] A channel area of ​​the sub-connection groove can be configured such that it becomes larger downstream in the direction of flow, i.e., in the direction of flow from the inlet chamber to the back pressure chamber.

[0024] In this case, the pressure of the fuel flowing through the sub-connecting groove decreases upon reaching the downstream side. This pulls the fuel flowing through the connecting and sub-connecting grooves downstream, allowing it to flow more easily from the inlet chamber into the back pressure chamber. This reduces the time required for pressure recovery before the valve element moves, further improving the valve element's responsiveness at valve closing time.

[0025] For example, the cylindrical inner wall section can be provided with connecting grooves that are uniformly offset from each other in the circumferential direction of the cylindrical inner wall section, the limiting section can be provided with sub-connecting grooves that are connected to the multiple connecting grooves accordingly and are uniformly offset from each other in the circumferential direction, and the connecting grooves and the sub-connecting grooves can be uniformly offset from each other in the circumferential direction.

[0026] In this case, the channel area of ​​the passage through which the fuel flows from the inlet chamber to the back-pressure chamber can be easily enlarged. Furthermore, by uniformly spacing the multiple connecting grooves and sub-connecting grooves circumferentially around the control element, the fuel can flow uniformly around the control element. This limits the tilt or deflection of the control element. As described above, by enlarging the channel area during the stabilization of the release plate or floating plate position, pressure recovery in the back-pressure chamber can be achieved quickly and easily. Thus, the movement time of the valve element can be shifted further forward, and the time variation can be small. Therefore, the response or responsiveness of the valve element at the valve closing time can be continuously enhanced.

[0027] Furthermore, the bottom section of the connecting groove can have a circular arc cross-section in the radial direction, and the sub-connecting groove can be configured in a circular arc shape that is coaxial to the bottom section and has the same radius as the bottom section.

[0028] Thus, when forming the connecting grooves and sub-connecting grooves on the valve body by cutting, the cutting process for forming the connecting grooves and sub-connecting grooves can be performed simultaneously with the same tool. Therefore, due to the configuration for the simultaneous formation of the connecting groove and sub-connecting groove, it is possible to supply the valve body with both the connecting groove and the sub-connecting groove at a low cylinder manufacturing cost. This allows the responsiveness of the valve element to be improved at a lower manufacturing cost for both the valve closing time and the valve opening time in the fuel injection device.

[0029] Furthermore, the center of the circular arc of the sub-connecting groove can be located on an inner circumferential side of the restricting section in its radial direction. In this case, the channel area of ​​the sub-connecting groove increases in the flow direction from the inlet chamber to the back-pressure chamber as it approaches downstream in the flow direction. This allows the fuel to flow smoothly from the inlet chamber into the back-pressure chamber, further improving the responsiveness of the valve element at valve closing time.

[0030] Furthermore, the cylindrical inner wall section can be knurled to form the connecting grooves. Even in this case, fuel can flow from the inlet chamber to the back pressure chamber. A preferred knurling method in this case is, for example, knurling as defined in JISB-0951, such as parallel knurling, in which several grooves extend along the axial direction, or diamond knurling, in which each groove intersects another, creating the diamond pattern.

[0031] Furthermore, the configuration of the connecting groove, which extends axially along the valve body, reduces the resistance to high-pressure fuel flow through the groove. This allows the fuel to flow more easily from the inlet chamber to the back pressure chamber. Consequently, the time required for pressure recovery in the back pressure chamber can be shortened, further improving the valve body's responsiveness at valve closure.

[0032] Furthermore, the configuration of the connecting groove is not limited to the shape extending along the axial direction, so that the connecting groove can, for example, also extend spirally around the central axis of the cylindrical inner wall section.

[0033] Furthermore, the valve body can be provided with a supply passage through which the high-pressure fuel flows into the injection port located at its tip end, and can have a cylindrical element which is held in the supply passage, configures the cylindrical inner wall section on the inner circumferential side and separates the pressure control chamber from the supply passage.

[0034] Furthermore, the valve body can contain a nozzle element that forms the tip end at which the injection port is provided, wherein the nozzle element represents the pressure control chamber defined by the cylindrical inner wall section and the supply passage located on an outer circumferential side of the pressure control chamber and feeding the high-pressure fuel into the injection port.

[0035] As described above, the component defining the pressure control chamber can be modified depending on the fuel injection device configuration. However, regardless of the component defining the pressure control chamber, pressure recovery in the back pressure chamber can be achieved quickly if the connecting groove is formed on the cylindrical inner wall section that defines the pressure control chamber, allowing fuel to flow into the back pressure chamber. Thus, forming the connecting groove, regardless of the fuel injection device configuration, results in an improvement in the valve element's responsiveness at valve closing time. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Fig. Figure 1 shows a schematic diagram of a fuel supply system with a fuel injection device according to a first embodiment of the present invention;

[0037] Fig. 2 shows a longitudinal sectional view of the fuel injection device according to the first embodiment of the present invention;

[0038] Fig. Figure 3 shows a partially enlarged view representing a section of the fuel injection device according to the first embodiment of the present invention;

[0039] Fig. Figure 4 shows an enlarged partial view representing the section of the fuel injection device according to the first embodiment of the present invention;

[0040] Fig. Figure 5 shows a cross-sectional view along a line VV in Fig. 4, which represents a embodiment of the connecting groove of the first embodiment;

[0041] Fig. Figure 6 shows a partially enlarged view representing part of the fuel injection device according to a second embodiment of the present invention, which is a modification example of Fig. 4 is;

[0042] Fig. Figure 7 shows a cross-sectional view along a line VII-VII in Fig. 6, which is a modification example of Fig. 5 represents;

[0043] Fig. Figure 8 shows a partially enlarged view showing a section of the fuel injection device according to a third embodiment of the present invention and a cross-sectional view along a line VII-VII in Fig. 9 shows a floating plate held in a cylinder;

[0044] Fig. Figure 9 shows a cross-sectional view along a line IX-IX in Fig. 8, which represents a structure of a connecting groove and a sub-connecting groove of the third embodiment according to the present invention;

[0045] Fig. Figure 10 shows a cross-sectional view representing a section of a fuel injection device according to a fourth embodiment of the present invention, which is a modification example of Fig. 7 is;

[0046] Fig. Figure 11 shows a cross-sectional view representing a section of a fuel injection device according to a fifth embodiment of the present invention, which is a further modification example of Fig. 7 is;

[0047] Fig. Figure 12 shows a cross-sectional view along a line XII-XII in Fig. 6 and represents a section of a fuel injection device for describing a connecting groove according to a sixth embodiment of the present invention;

[0048] Fig. Figure 13 shows a cross-sectional view representing a section of a fuel injection device according to a seventh embodiment of the present invention, which is a modification example of Fig. 12 is; and

[0049] Fig. Figure 14 shows a cross-sectional view representing a section of a fuel injection device according to the seventh embodiment of the present invention, which is a further modification example of Fig. 3 is. Preferred methods for implementing the invention

[0050] Various embodiments of the present invention are described with reference to the accompanying drawings. In the following embodiments, similar or corresponding components are provided with the same reference numerals, thereby omitting redundant descriptive sections. (First embodiment)

[0051] A fuel supply system 10, in which a fuel injection device 100 as used according to a first embodiment of the present invention, is in Fig. 1 shown. The fuel supply system 10 is a so-called direct injection fuel supply system, in which fuel is injected into a combustion chamber 22 a diesel engine 20 as a combustion engine, it is injected directly.

[0052] The fuel supply system 10 consists of a feed pump 12 , a high-pressure fuel pump 13 , a common rail 14 , a machine control device 17 (Machine ECU), the fuel injection device 100 , and the like.

[0053] The feed pump 12 is an electrically driven pump and is located in a fuel tank 11 recorded. The feed pump 12 This creates a pressure on the fuel in the fuel tank. 11stored fuel at a pressure higher than the fuel's vaporization pressure. The feed pump 12 is with the high-pressure fuel pump 13 via a fuel line 12a connected and carries the fuel, which is pressurized to a predetermined supply pressure, to the high-pressure fuel pump 13 in liquid state. The fuel line 12a It features a pressure control valve (not shown) fitted within it, and the pressure of the fuel that supplies the high-pressure fuel pump 13 The amount supplied is maintained at a fixed value.

[0054] The high-pressure fuel pump 13 is on the diesel engine 20 It is attached and powered by an output shaft of the diesel engine. 20 controlled. The high-pressure fuel pump 13 is with the common rail 14 via a fuel line 13aconnected, and furthermore brings pressure to the fuel which is supplied by the feed pump 12 is supplied to, in order to the common rail 14 to supply high-pressure fuel. Furthermore, the high-pressure fuel pump features 13 an electromagnetic valve (not shown) that is connected to the machine control device 17 It is electrically connected. The electromagnetic valve is controlled by the machine control device. 17 opened or closed, thereby changing the pressure of the fuel supplied by the high-pressure fuel pump. 13 to the common rail 14 The fluid supplied is optimally controlled to a preset pressure.

[0055] The common rail 14 is a tubular element made of metal such as chromium-molybdenum steel and has a plurality of branching parts 14a The number of branch sections. 14aThis corresponds to the number of cylinders per bank of the diesel engine. Each of the branch sections 14a is with the fuel injection device 100 via a fuel line that has a supply channel 14d forms, connected. The fuel injection device 100 and the high-pressure fuel pump 13 are connected by a fuel line that includes a return channel 14f trains, connected. According to the aforementioned structure, the common rail stores 14 temporarily the fuel that passes through the high-pressure fuel pump 13 It is supplied under high pressure and distributes the fuel to the majority of the fuel injection devices. 100 with the pressure maintained in the high-pressure state through the supply channels 14d Furthermore, the common rail exhibits 14 a common rail sensor 14bon, which is provided at one end section of the two end sections in the axial direction, and has a pressure regulator 14c on, which is provided at its other end. The common-rail sensor is connected to the machine control device. 17 electrically connected, it measures the pressure and temperature of the fuel and transmits these values ​​to the engine control unit. 17 off. The pressure regulator 14c maintains the fuel pressure in the common rail. 14 At a constant value, it decompresses excess fuel and releases it to a low-pressure side. The excess fuel, which passes through the pressure regulator, 14c This happens through a channel in a fuel line 14e , which the common rail 14 with the fuel tank 11 connects to the fuel tank 11 returned.

[0056] The fuel injection device 100is the device for pressurizing the fuel and injecting the high-pressure fuel, which passes through the branch section 14a the common rail 14 is supplied from an injection port 44 More precisely, the fuel injection device features 100 a valve section 50 on, which is the injection of the high-pressure fuel, which is from the injection port 44 The injection is based on a control signal from the machine control device. 17 controls. The high-pressure fuel is pumped by the high-pressure pump. 13 through the feed channel 14d supplied. Additionally, it is used in the fuel injection system. 100 the excess fuel, which is part of the high-pressure fuel that comes from the supply channel 14d is supplied and not from the injection opening 44 is injected into the return channel 14f, through which the fuel injection device 100 with the high-pressure fuel pump 13 is connected, omitted, and then to the high-pressure fuel pump 13 returned. The fuel injection device 100 is in an injection opening which is in a head element 21 , which is located in a section of the combustion chamber 22 the diesel engine 20 It is arranged, inserted, and fitted. In the present embodiment, a plurality of fuel injection devices are 100 for the respective combustion chambers 22 the diesel engine 20 arranged, and each of them injects the fuel directly into the combustion chamber 22 one, more precisely, with an injection pressure in the range between 160 and 220 MPa.

[0057] The machine control device 17consists of a microcomputer or similar device. The machine control unit 17 is not only with the common rail sensor described above 14b , but also with various sensors such as a speed sensor to detect the rotational speed or rotational speed of the diesel engine 20 The machine control device is electrically connected to a throttle sensor for detecting throttle valve opening, an air flow sensor for detecting intake air volume, a boost pressure sensor for detecting boost pressure, a water temperature sensor for detecting coolant temperature, and an oil temperature sensor for detecting the oil temperature of a lubricating oil. 17 It is used to control the opening / closing of the electromagnetic valve of the high-pressure fuel pump. 13 and the valve section 50 from each fuel injection device 100Based on the signal from the respective sensors, an electrical signal is sent to the electromagnetic valve of the high-pressure fuel pump. 13 and to each fuel injection device 100 out of.

[0058] Next, based on Fig. 2 or Fig. 3. The design of the fuel injection device 100 described in detail.

[0059] The fuel injection device 100 contains a control valve actuator 30 , a control body 40 , a jet needle 60 , a feather 76 and a floating plate or movable plate 70 .

[0060] The control valve control unit 30 is in the control body 40 recorded. The control valve actuator. 30 includes a connection 32 , a solenoid 31 , a fixed element 36 , a movable element 35 , a feather34 , and a valve seat element 33 The connection 32 , which consists of an electrically conductive material and has two end sections, has one end section that is located outside the control body 40 extends, and another end section that connects to the solenoid. 31 is connected. The solenoid 31 is wound in a spiral shape and is powered by a pulsed current from the machine control device 17 through the connection 32 powered or supplied. If the solenoid 31 is supplied with pulsed current, or this current is supplied to the solenoid. 31 When applied, the solenoid generates 31 A magnetic field that rotates along the axial direction. The fixed element 36 is a cylindrical element made of a magnetic material and is located in the area defined by the solenoid 31 The generated magnetic field magnetizes the movable element. 35It consists of magnetic material, has a cylindrical shape with two steps, and is located at one tip in the axial direction of the fixed or defined element. 36 arranged. The movable element 35 becomes a base end face in the axial direction through the magnetized fixed element 36 pulled. The spring 34 , which is a spiral spring formed by winding a metal wire in a circular shape, pushes the movable element 35 in one direction to move the movable element 35 from the fixed element 36 to space. The valve seat element 33 forms a pressure control valve 80 together with a control valve seat section 47a of the steering body 40 The control valve seat section 47a The valve seat element will be described later. 33 is on the opposite side of the fixed element 36 in the axial direction of the moving element 35arranged and on the control valve seat section 47a attached. When the magnetic field of the solenoid 31 If not generated, the valve seat element is located 33 through the restoring force of the spring 34 on the control valve seat section 47a up. When the magnetic field of the solenoid 31 The valve seat element is generated 33 from the control valve seat position 47a spaced apart.

[0061] The control body 40 , which has a nozzle body 41 , a cylinder 56 , an opening plane 46 , a holder 48 and a retaining nut 49 It has an elongated shape and contains a high-pressure fuel passage. The nozzle body 41 , the opening plane 46 and the holder 48They are arranged in this order from one point in the direction in which they are inserted into the combustion chamber. Furthermore, the injection port... 44 , through which the high-pressure fuel flows to the combustion chamber 22 (see Fig. 1) the diesel engine 20 is injected at one tip of the control body. 40 arranged.

[0062] The control body 40 features an inlet channel 52 , an outlet channel 54 , a pressure control chamber 53 and one for the pressure control chamber 53 showing opening wall surface 90 open. One end of the intake channel 52 is connected to one side of the feed channel 14d (see Fig. 1), which is connected to the high-pressure fuel pump 13 and the common rail 14 is connected, in connection, and the other end of the inlet channel 52 is connected to the pressure control chamber 53in connection. The inlet channel 52 shows an opening of an inlet connection 52a , which forms a passage end opposite one side of the feed channel 14d is on the opening wall side 90 This allows the high-pressure fuel to pass through the intake port. 52 into the pressure control chamber 53 to be introduced. Furthermore, there is an end to the outlet channel. 54 with one side of the feedback channel 14f (see Fig. 1) the one with the high-pressure fuel pump 13 is connected, in connection, and the other end of the outlet channel 54 is connected to the pressure control chamber 53 in connection. The outlet channel 54 has an opening of an outlet connection 54a , which forms a passage end opposite one side of the return channel 14f is, on the opening wall surfaces 90 This allows the fuel to enter the pressure control chamber. 53through the outlet channel 54 flow to the low-pressure side. The pressure control chamber 53 is through the opening plate or opening plane 46 and the cylinder 56 defined. The pressure control chamber 53 is in the control body 40 regarding the jet needle 60 on one side opposite the injection opening 44 planned. The pressure control chamber 53 is configured in such a way that the high-pressure fuel is drawn from the inlet channel 52 inserted and through the outlet channel 54 is drained.

[0063] The nozzle body 41 It consists of metal, such as chromium-molybdenum steel, and has a cylindrically shaped base section. The nozzle body 41 features a nozzle body housing section 43 , a valve seat section 45 and an injection port 44 The nozzle body housing section 43is along the axial direction of the nozzle body 41 formed, and is a cylindrical opening in which a nozzle needle 60 is recorded. In the nozzle needle housing section 43 high-pressure fuel is contained within, supplied by the high-pressure fuel pump. 13 and the common rail 14 is supplied (see Fig. 1) A feed passage 43a , through which the high-pressure fuel flows to the injection opening 44 The flow is guided through the nozzle needle housing section. 43 and the cylinder 56 defined. The valve seat section 45 is on the bottom wall of the nozzle needle housing section 43 formed and touches the tip of the nozzle needle 60 The injection port 44 is at the tip of the nozzle body 41 arranged which, with respect to the valve seat element section 45 opposite to the opening plate 46 is. From the injection ports44 , which originate from inside the nozzle body 41 Multiple jets are formed when the fuel radiates outwards. When the high-pressure fuel passes through the injection opening... 44 Once it reaches the air, the high-pressure fuel is atomized and atomized, allowing the fuel to mix well with the air.

[0064] The cylinder 56 , which is made of a metallic material, defines the pressure control chamber 53 in the radial direction of the chamber 53 Furthermore, the cylinder 56 coaxial in the nozzle needle housing section 43 recorded and defines the feed passage 43a and the pressure control chamber 53 .

[0065] The cylinder 56 has an interior wall surface section 56a on, which has a cylindrical shape. The inner wall surface section 56a is with a control wall surface section 57 , a cylindrical displacement surface section 59, a plate stopper section 58a and a needle stopper section 58b equipped. The control wall surface section 57 is on one side of the valve body 46 in the axial direction of the cylinder 56 arranged and encompasses the perimeter of the opening wall surface 90 The cylindrical displacement surface section 59 is located at a point opposite the aperture plate or opening plate 46 in the axial direction of the cylinder 56 is, so that the jet needle 60 movable on the cylinder displacement surface section 59 along the axial direction. An inner diameter of the cylindrical displacement surface section. 59 is with respect to an inner diameter of the control wall surface section 57 reduced.

[0066] The plate stopper section 58aexhibits a stepped shape, which extends towards a radial inner side of the inner wall surface section. 56a extends, and is defined by the difference between the inner diameter of the cylinder displacement surface section. 59 and the control wall surface section 57 configured or defined. The plate stop section 58a lies opposite the floating plate 70 in the axial direction of the cylinder 56 The plate stopper section 58a is configured, the floating disk 70 by shifting them from the inlet channel 52 to touch in such a way that the displacement of the floating plate 70 towards the jet needle 60 can be controlled. The needle stopper section 58b is located on an opposite side, which is opposite to the control wall surface section 57 regarding the cylinder displacement surface section 59in the axial direction of the cylinder 56 is. The needle stopper section 58b is opposite a side that is opposite the plate stop section 58a in the axial direction of the cylinder 56 is, so that the displacement of the jet needle 60 towards the floating plate 70 can be controlled.

[0067] The opening plate 46 , which is made of metal, such as chromium-molybdenum steel, has a cylindrically shaped element and is located between the nozzle body 41 and the holder 48 held. The opening plate 46 includes the control valve seat section 47a , the opening wall surface 90 , the outlet channel 54 and the intake channel 52 The control valve seat section 47a is at one end face of the opening plate 46 arranged, which one side of the holder 48 in the axial direction of the opening plate46 is, and is configured or defined together with the valve seat element 33 of the control valve control unit 30 the pressure control valve 80 The opening wall surface 90 is a flat surface which is located on or at one side of the nozzle body 41 arranged and in a central position in the radial direction of the other end face of the opening plate 46 is configured. The opening wall area 90 is through the cylinder 56 It is surrounded and has a circular shape. The outlet channel 54 extends towards the control valve seat section 47a from a radial central section of the opening wall surface 90 The outlet channel 54 is with respect to the axial direction of the opening plate 46 inclined. The intake channel 52 extends towards one end surface, which is the control valve seat section 47aexhibits, from the radial outside of the outlet channel 54 into the opening wall surface 90 The intake channel 52 is with respect to the axial direction of the opening plate 46 inclined.

[0068] The holder 48 is an element made of a metallic material, such as chromium-molybdenum steel, in the form of a cylinder, and has elongated holes 48a , 48b along the axial direction, and has a base section 48c The elongated hole 48a is a fuel channel that connects to the supply channel 14d (see Fig. 1) with the inlet channel 52 connects. The elongated hole 48b It contains the control valve control unit. 30 on one side of the opening plate 46 on. Also, in the elongated hole 48b the base section 48c in a section opposite the opening plate 46 configured to open the elongated hole 48bto block the base section 48c indicates an end of the connection 32 of the control valve control unit 30 , which extends into it, and a plug section (not shown) that is removablely fitted into it. The plug section is connected to the machine control device. 17 connected. If the base section 48c which is connected to the plug section (not shown), can be connected to the control valve control unit. 30 from the machine control device 17 A pulsed current is transmitted.

[0069] The retaining nut 49 It consists of a metallic material and has a two-stage cylindrical shape. The retaining nut 49 takes up a section of the nozzle body 41 and the opening plate 46 up and is on the side of the opening plate 46 the holder 48 provided with a thread. Furthermore, the retaining nut has 49a stepped section on its inner perimeter wall section 49a open. If the retaining nut 49 on the holder 48 The stepped section expresses the fit. 49a the nozzle body 41 and the opening plate 46 towards the holder 48 . In this way the retaining nut holds 49 the nozzle body 41 and the opening plate 46 with the holder 48 together.

[0070] The jet needle 60 , which is made of a metallic material, such as high-speed tool steel, is configured as an essentially cylindrical shape and can be located in the control body 40 moved in the axial direction. The jet needle 60 features a seating section 65 , a pressure-bearing surface 61 , a spring housing section 62 , a needle displacement section 63 , a needle anchoring section 68, a return spring 66 and a collar element 67 up. The seating area 65 is at an end section, which is one of the two end sections in the axial direction of the jet needle 60 is, trained, opposite to the pressure control chamber 53 arranged and on the valve seat section 45 of the steering body 40 attached. The seat section 65 and the valve seat section 45 define a valve section 50 , which is the injection port 44 , through which the high-pressure fuel, which enters the nozzle needle housing section 43 is guided, omitted, opens or closes.

[0071] The pressure-bearing surface 61 is designed as an end section, which separates one end from the two end sections in the axial direction of the nozzle needle 60 is, and on one side of the pressure control chamber 53 opposite the seating section 65arranged. The pressure-bearing surface 61 separates the pressure control chamber 53 together with the opening wall surface 90 and the control wall surface section 57 , and takes the pressure of the fuel into the pressure control chamber 53 This results in the displacement of the jet needle. 60 through the fuel pressure in the pressure control chamber 53 controlled. The spring housing section 52 is a cylindrical opening or hole, which is coaxial to the nozzle needle 60 and in a radial central section of the pressure-bearing surface 61 is arranged. The spring housing section 62 takes a section of a spring 76 on.

[0072] The needle displacement section 63 , which is a section of the round, barrel-shaped outer circumferential wall of the nozzle needle 60 is closer to the pressure-bearing surface 61 as the control wall surface section57 arranged. The needle displacement section 63 is through the cylinder displacement surface section 59 , which passes through the inner circumferential wall of the cylinder 56 The collar element is defined as being slidably mounted. 67 is a ring-shaped element that is attached to the outer circumferential wall section of the nozzle needle 60 It fits and goes through the jet needle. 60 is held. The needle anchorage section 68 is on the side of the seating section 65 relative to the nozzle needle displacement section 63 mounted in the axial direction, and is a stepped section created by increasing or widening the outer diameter of the nozzle needle. 60 is configured. The needle anchor section 68 defines an area which corresponds to the needle stopper section 58b of the cylinder 56 in the axial displacement direction of the nozzle needle 60opposite. The needle anchor section 68 is with the needle stopper section 58b locked in such a way that the displacement of the jet needle 60 towards the floating plate 70 is limited.

[0073] The jet needle 60 is on one side of the valve section 50 by a return spring 66 pre-tensioned. The return spring 66 It is a spiral spring formed by circularly winding a metal wire. The return spring 66 has an end in the axial direction that is located on a side surface of the pressure control chamber 53 of the collar element 57 is attached, with the other end correspondingly on an end face of the valve section side of the cylinder. 56 is attached. According to the design described above, the nozzle needle 60 in the axial direction of the cylinder 56 regarding the cylinder 56in response to the pressure exerted on the pressure-receiving surface 61 is applied, i.e., the pressure of the fuel in the pressure control chamber 53 moved linearly back and forth to move the seat section 65 on the valve seat section 45 to set or the seating section 65 from the valve seat section 45 to space it apart, whereby the valve section 50 is closed or opened.

[0074] The floating plate 70 , which consists of a metallic material and is designed as a round disc body, presses against the opening wall surface 90 such that they open the inlet channel 52 blocked. The floating plate 70 has a printing surface 73 , a pressure-bearing surface 77 , a plate anchoring section 78 , an outer perimeter wall surface section 74 and a connecting hole 71 up. The floating plate 70is for back-and-forth movement in the axial direction of the cylinder 56 of the control body in the pressure control chamber 53 Arranged in a sliding manner. The floating plate. 70 exhibits a displacement axis direction that runs along the axial direction of the nozzle needle 60 This is the case for both end faces in the displacement axis direction of the floating plate. 70 The end surface is opposite to the opening wall surface. 90 in the direction of the displacement axis, the pressure surface section 73 out. The pressure area section 73 , which is round or ring-shaped, is bordered by the back-and-forth movement of the floating plate 70 to the opening wall surface 90 The end surface of the floating plate 70 , which are opposite to the pressure surface 73 The pressure-bearing surface lies in the direction of the displacement axis. 77 from which of the pressure-bearing surface 61is opposite in the direction of the displacement axis. The pressure-bearing surface 77 is caused by the pressurized fuel in the pressure control chamber 53 towards the opening wall surface 90 pressed.

[0075] Furthermore, the outer circumferential edge of the print-bearing surface 77 the plate anchoring section 78 , which belongs to the plate stopper section 58a of the cylinder 56 is opposite in the direction of the displacement axis. The plate anchorage section 78 is with the plate stop section 58a locked in such a way that the movement of the floating plate is prevented 70 towards the jet needle 60 is limited.

[0076] The outer perimeter wall surface section 74 the floating plate 70 , which defines the printing area 73 with the pressure-receiving surface 77 connecting is the control wall surface section 57in the radial direction of the cylinder 56 On the contrary. Furthermore, there is an entrance chamber. 53a a space located on one side of the inlet channel 52 relative to the floating plate 70 in the pressure control chamber 53 is positioned. In addition, there is a counter-pressure chamber. 53b a space located on one side of the nozzle needle 60 relative to the floating plate 70 in the pressure control chamber 53 is positioned.

[0077] The connecting hole 71 extends from the radial central section of the pressure-bearing surface 77 to the outlet opening 54a in the floating plate 70 The direction of extension of the connecting hole 71 is along the displacement axis of the floating plate. One end of the connecting hole 71 is on the radial central section of the pressure surface 73 , which of the outlet opening 54ais open in the opposite direction. The pressure control chamber 53 is aligned with the outlet opening 54a through the connecting hole 71 in a connected state in which the printing surface 73 the floating plate 70 to the opening wall side 90 borders.

[0078] The connecting hole 71 has a tapered section 71a and an in-depth section 72 open. A tiny section of the connecting hole. 71 is due to the size of the tapered section 71a defined in such a way that the tapered section 71a the volume flow of fuel passing through the connecting hole 71 flows, controls. The canal area of ​​the narrowed section 71a is smaller than the opening area of ​​the outlet opening 54a The rejuvenated section 71a is positioned closer to the end surface, which is one of the two end surfaces of the floating plate70 in whose axial direction and the pressure surface 73 forms, as on the other end surface, which is the pressure-bearing surface 77 trains. The advanced section 72 , which is coaxial with the floating plate 70 and a cylindrical hole is, is from the pressure-bearing surface 77 to one side opposite the pressure-bearing surface 61 so deepened or excavated that the channel area of ​​the connecting hole 71 through the in-depth section 72 is partially enlarged. The opening of the connecting hole. 71 in the pressure-bearing area 77 is through the in-depth section 72 enlarged. The pressure-bearing surface 77 However, it is due to the spring 76 Prestressed in the direction of the displacement axis.

[0079] The spring 76 A coil spring is a spiral spring made by winding a metal wire in a circular motion.76 has an end in the axial direction that rests on the pressure-receiving surface 77 the floating plate 70 is attached. The spring 76 has the other end in the axial direction, which is in the spring housing section 62 the jet needle 60 is recorded. The spring 76 is coaxial between the floating plate 70 and the jet needle 60 arranged and provided in a compressed form in the axial direction.

[0080] According to the above design, the spring tensions 76 the floating plate 70 to the side of the opening wall surface 90 regarding the jet needle 60 even if there is a pressure difference between the inlet chamber 53a and the counter-pressure chamber 53b The floating plate is small. 70 due to the preload force of the spring 56 on the opening wall surface 90 pre-stressed, whereby the pressure surface section73 on the opening wall surface 90 adjacent to or resting on it.

[0081] Next, the illustrated section of the fuel injection device will be discussed. 100 with reference to Fig. 3 and Fig. 5 described in detail.

[0082] In the interior wall surface section 56a of the cylinder 56 are a connecting groove 57a and a movable contact wall surface 57b arranged. The connecting groove 57a extends from an axial end of the cylinder 56 , which is the side of the opening wall surface 90 in the axial direction of the cylinder 56 is, to the plate stopper section 58a along the axial direction of the cylinder 56 that the connecting groove 57a the entrance chamber 53a with the counter-pressure chamber 53b connects. In the interior wall surface section 56a are several connecting grooves 57aprovided and spaced apart from each other circumferentially by a predetermined distance. More precisely, according to the first embodiment, three connecting grooves are provided. 57a in the interior wall surface section 56a The connecting groove is designed and equidistant from each other in the circumferential direction. 57a points in the circumferential direction of the cylinder 56 an arc-shaped cross-section and a central angle of the arc-shaped connecting groove 57a is approximately 90°.

[0083] The connecting groove 57a is through a section of ground 57d defines which one runs along the circumferential direction of the cylinder 56 is provided for, and a side section 57e , which runs along the radial direction of the cylinder 56 is provided. In cross-section in the radial direction of the cylinder. 56 is a corner section 57f , which is the section of ground 57d and the side section 57econnects, forming a circular arc. As described above, this is achieved by forming the corner section. 57f in arc shape the force which is exerted by the pressurized fuel passing through the connecting groove 57a flows onto the interior wall surface section 56a is applied to the corner section 57f concentrated.

[0084] The movable contact wall surface 57b is between the connecting grooves 57a , which leads to the movable contact wall surface 57b in the circumferential direction of the cylinder 56 are adjacent, arranged. The movable contact wall surface 57b contacts or touches the outer perimeter wall surface section 74 around the displacement axis of the floating plate 70 Adjustable. The connecting grooves 75a are spaced equally apart from each other in the circumferential direction, such that three movable contact wall surfaces 57bin the circumferential direction of the cylinder 56 are equally spaced. Therefore, the contact sections between the movable contact wall surface are 57b and the outer perimeter wall surface section 74 spaced apart from each other by approximately 120°, so that the floating plate 70 through the movable contact wall surface 57b inwards in the radial direction of the floating plate 70 is held.

[0085] Furthermore, even between the movable contact wall surface 57b and the outer perimeter wall surface section 74 A small fuel flow, such as a very small fuel leak, can occur. However, if a total channel area through which the fuel flows from the intake chamber... 53a to the counter-pressure chamber 53bflow, is determined, the total channel area to obtain the required flow without taking into account the volume of fuel that flows between the movable contact wall surface 57b and the outer perimeter wall surface section 74 and into the counter-pressure chamber 53b flows, defined. Thus, the channel area of ​​the connecting groove is defined. 57a , the radial groove 77a , which extends in a radial direction, and the connecting hole 71 defined in such a way that the required amount of fuel flow, which is supplied by the intake chamber 53a to the counter-pressure chamber 53b flows, by forming three connecting grooves 57a and the three radial grooves 77a determined to use the connecting hole 71 to communicate or to be in contact with it. Furthermore, the total channel areas of the three connecting grooves are 57a and the connecting hole 71larger than the opening area of ​​the inlet opening 52a determined.

[0086] Furthermore, the plate anchoring section 78 the floating plate 70 with the multiple radial grooves 77a provided. The multiple radial grooves 77a They are spaced apart from each other in the circumferential direction. The radial grooves 77a extend in the radial direction of the floating plate 70 The radial groove 77a forms a passage through which the fuel flows between the plate anchoring section 78 and the plate stopper section 58a can flow.

[0087] Next, the operation of the fuel injection system will be performed. 100 , which controls the opening / closing of the valve section 50 controls and according to a control signal from the machine control device 17 is dispensed, fuel is injected, based on the Fig. 2 to Fig. 5 described.

[0088] In a state where the pressure control valve 80 the outlet opening 54a and the return channel 14f blocked (see Fig. 1) the printing surface 73 the floating plate 70 by means of the spring preload 76 towards the closed position of the inlet channel 52 on the opening wall surface 90 on. If the outlet channel 54a with the feedback channel 14f through the operation of the pressure control valve 80 Once connected, the fuel begins to flow in the pressure control chamber. 53 through the outlet channel 54 to flow out. This creates a point adjacent to the outlet opening. 54a such decompression that the floating plate 70 towards the opening wall surface 90 is pulled, the pressure area 73 on the opening wall surface 90presses and the inlet opening 52a is blocked.

[0089] The fuel in the counter-pressure chamber 53b the pressure control chamber 53 flows through the connecting hole 71 from the outlet opening 54a If the flow from the outlet opening 54a As the process progresses, the fuel pressure in the pressure control chamber will increase. 53 reduced. If the fuel pressure in the pressure control chamber 53 If the pressure falls below a predetermined value, the nozzle needle will... 60 towards the pressure control chamber 53 moved, so that the seat section 65 from the valve seat section 45 is spaced apart, which causes the valve section to 50 opens. In the following description, the pressure at the point in time when the nozzle needle begins to move will be referred to, for simplicity, as the predetermined pressure. The movement of the nozzle needle is then described. 60towards the pressure control chamber 53 through the attachment of the needle anchoring section 68 at the needle stopper section 58b limited.

[0090] If the communication or connection between the outlet opening 54a and the return channel 14f (see Fig. 1) by closing the pressure control valve 80 If interrupted, the floating plate 70 through the high-pressure fuel that passes through the intake port 52 is inserted in the direction of the jet needle 60 pressed. When the force exerted by the high-pressure fuel in the intake port 52 is generated and moves towards the jet needle 60 acts higher than the preload force of the spring 76 which is directed towards the opening wall surface 90 The floating plate takes effect. 70 to shift. Spacing the floating plate 70 from the opening wall surface 90results in a connection between the intake channel 52 and the pressure control chamber 53 This results in high-pressure fuel entering the intake chamber. 53a introduced. The displacement of the floating plate 70 towards the jet needle 60 is due to the purpose of the plate anchoring section 78 at the plate stop section 58a limited.

[0091] Then the fuel flows, which comes from the intake port. 52 into the entrance chamber 53a is introduced through the three connecting grooves 57a and the three radial grooves 77a , which are located on the interior wall surface section 56a of the cylinder 56 are arranged, and the connecting hole 71 into the counter-pressure chamber 53b Through pressure recovery in the counter-pressure chamber 53b will the jet needle 60 towards the valve section 50pressed downwards. Thus, the jet needle causes 60 that the seat section 65 on the valve seat section 45 is placed on top and the injection opening or injection hole 44 blocked.

[0092] Even after the valve section 50 When the valve is closed, the fuel flow proceeds from the intake chamber. 53a to the counter-pressure chamber 53b forward. Thus, the pressure difference between the inlet chamber 53a and the counter-pressure chamber 53b in the pressure control chamber 53 Gradually reduced. Thus, the spring preload is reduced. 56 greater than the force of the floating plate 70 , which in the direction of the jet needle 60 It works, so that the floating plate 70 the plate anchoring section 78 from the plate stopper section 58a spaced apart and in the direction of the opening wall surface 90shifts. Then the floating plate moves. 70 back to the state in which the printing surface 73 due to the preload force of the spring 76 on the opening wall surface 90 is pending.

[0093] In the first embodiment, the channel area is sufficient or suitable to allow fuel flow from the inlet channel. 53a to the counter-pressure chamber 53b through the connecting grooves 57a This creates pressure recovery in the counter-pressure chamber. 53a through the floating plate 70 Basically, not restricted.

[0094] However, the gap between the inner wall surface section can 56a of the cylinder 56 and the outer perimeter wall surface section 74 the floating plate 70 due to the creation of sufficient channel area by the connecting grooves 57aThe gap can be reduced. By reducing or narrowing the gap, the inclination of the displacement axis of the floating plate can be adjusted. 70 relative to the axial direction of the cylinder 56 be limited. Thus, the floating plate 70 easily movable and can be used in the pressure control chamber 53 can be moved. Thus, the floating plate allows it to be moved. 70 the inlet channel 52 into the pressure control chamber 53 They can be opened quickly. Therefore, the introduction of fuel into the pressure control chamber is 53 not through the floating plate 70 limited.

[0095] Thus, if the floating plate 70 the inlet channel 52 When it opens, the fuel quickly enters the intake chamber. 53a inserted and can be easily moved into the counter-pressure chamber 53b flow. This can result in a time that is needed for printer recovery during the start-up phase of the nozzle needle shift.60 The required reaction time can be shortened. Therefore, the responsiveness of the nozzle needle can be reduced. 60 in the fuel injection device 100 The valve closure time can be improved.

[0096] Furthermore, according to the first embodiment, the channel area of ​​the passage is sufficient for connecting or communicating with the inlet channel. 53a with the counter-pressure chamber 53b through the connecting groove 57a created. Thus, even if the movable contact wall surface 57b , which defines the outer perimeter wall surface section 74 the floating plate 70 Movable contact, on the inner wall surface section 56a of the cylinder 56 is arranged to prevent pressure recovery in the counter-pressure chamber 53a through the floating plate 70 is interrupted. The floating plate 70 is attached to the movable contact wall surface 57bshifted and moved back and forth in such a way that the axis of the floating plate is tilted. 70 can be limited. Thus, the floating plate 70 in the pressure control chamber 53 so precisely shifted and moved back and forth that the high-pressure fuel introduction into the intake channel 53a is not interrupted. Therefore, the time required for pressure recovery in the counterpressure chamber is 53a is required, shortened so precisely that the reaction capacity of the nozzle needle 60 The valve closure time can be further improved.

[0097] According to the first embodiment, the high pressure of the high-pressure fuel acts on the connecting groove. 57a , through which the high-pressure fuel flows. In the radial direction of the cross-section of the connecting groove 57a is the corner section 57f between the floor section 57d and the side section 57ethe connecting groove 57a shaped in a circular arc, so that it can be prevented from hitting the corner 57f excessive stress has an effect. Furthermore, the connecting groove 57a It is curved and extends in the circumferential direction in such a way that the above-described sufficient channel area is created, and the connecting groove 57a It can be formed with a shallow depth in the radial direction. Therefore, it is easy to achieve a sufficiently thick cylinder wall. 56 to create in the radial direction that the aging or decrease in load-bearing capacity of the cylinder 56 This can limit the wear and tear on the cylinder. 56 , which is achieved by providing the connecting groove 57a is caused, but can be limited. Therefore, the responsiveness of the jet needle can be limited. 60 at the valve closing time in the fuel injection device 100be improved, while ensuring the longevity of the fuel injection system 100 is achieved.

[0098] According to the first embodiment, the three connecting grooves 57a separately from each other in the circumferential direction such that the channel area of ​​the passage through which the fuel flows from the inlet chamber 53a into the counter-pressure chamber 53b The flow can be easily increased. This allows such a large volume of fuel to flow towards the backpressure chamber. 53b This ensures that pressure recovery occurs in the counter-pressure chamber. 53b can be reached quickly. Furthermore, the three connecting grooves 57a in the circumferential direction of the cylinder 56 arranged at equal intervals and spaced apart from each other, so that the fuel flows from the three sections into the counter-pressure chamber 53b flows. Thus, the fuel flow can around the floating plate. 70become uniform.

[0099] The provision of the three connecting grooves 57a This results in an increase in the flow rate of fuel entering the back pressure chamber. 53b flows, and the uniform fuel flow is ensured by the arrangement of the connecting grooves. 57a at equal intervals, so that the deflection or tilt of the floating plate 70 This can be limited relative to its axial direction. This restricts the pressure recovery in the counter-pressure chamber. 53b This is achieved quickly and easily. Thus, the start-up time of the jet needle is reduced. 60 It is positioned further forward, and the fluctuation or variation in the movement start time can be small. Therefore, the reaction time of the nozzle needle can be 60 at the valve closing time in the fuel injection device 100 can be improved.

[0100] Furthermore, according to the first embodiment, the design of the connecting groove can be 57a, which extend in the axial direction of the cylinder 56 extends, the resistance of the river through the connecting groove 56a This reduces the fuel flow from the intake chamber. 53a to the counter-pressure chamber 53b It can be made less frictional. Therefore, the time required for pressure recovery in the counter-pressure chamber can be reduced. 53b The required length is shortened to such an extent that the response or reaction capacity of the jet needle is reduced. 60 The valve closure time can be further improved.

[0101] Furthermore, according to the first embodiment, the plate stopper section 58a , which has a stepped section, in the cylinder 56 of the steering body 40 arranged in such a way that the displacement of the floating plate 70 in the direction of spacing from the inlet channel 52 is suitably limited by a simple structure. This closes the floating plate.70 at the moment the jet needle closes 60 quickly the intake channel 52 and stops the introduction of high-pressure fuel into the counter-pressure chamber 53 The fuel flow from the intake chamber 53a to the counter-pressure chamber 53b However, a connection between the plate anchoring section is possible. 78 and the plate stopper section 58a be restricted. According to the present embodiment, the radial groove 77a in the plate anchoring section 78 arranged in such a way that the fuel can flow even when the plate anchoring section 78 and the plate stopper section 58a are in contact. Thus, the function of the connecting groove can be fulfilled. 57a , which reduces the time for pressure recovery in the counter-pressure chamber 53b can be shortened, used effectively, without affecting the contact of the plate anchoring section. 78and the plate stopper section 58a is interrupted. Therefore, the responsiveness of the jet needle can be affected. 60 both the valve closing time and the valve opening time in the fuel injection device 100 can be improved.

[0102] According to the first embodiment, the diesel engine 20 An example of the combustion engine described in the claims, the control body 40 An example of the valve body described in the claims, the nozzle body 41 An example of the nozzle element described in the claims, the cylinder 56 an example of a cylindrical element described in the claims, the inner wall surface section 56a An example of a cylindrical inner wall section described in the claims, the nozzle needle 60 an example of a valve element described in the claims and the floating plate 70an example of a control element described in the claims. (Second embodiment)

[0103] A second embodiment of the present invention, which is described in the Fig. 6 and Fig. Figure 7 shows a modified example of the first embodiment described above. In a fuel injection device 200 In the second embodiment, a cylinder 256 corresponding to the cylinder 56 (see Fig. 3) of the first embodiment. Furthermore, the fuel injection device 200 on a design corresponding to the spring 76 (see Fig. 3) omitted in the first embodiment. Next, the detailed construction of the fuel injection device will be described. 200 as described in the second embodiment.

[0104] A connecting groove 257a and a movable contact wall surface 257bare in the interior wall surface section 256a of the cylinder 256 arranged. The connecting groove 257a and the movable contact wall surface 257b correspond to the one in the cylinder 56 the connecting groove arranged in the first embodiment 57a and the movable contact wall surface 57b (see Fig. 4).

[0105] The connecting groove 257a , which is the entrance chamber 53a with the counter-pressure chamber 53b connects, extending from one end of the cylinder 256 on the side of the opening wall surface 90 to a plate stop section 258a along the axial direction of the cylinder 256 In the second embodiment, the four connecting grooves 257a in the circumferential direction of the cylinder 256 provided at equal intervals. The connecting groove 257aIt has a semicircular cross-section in the radial direction. As described above, creating a floor section results 257d the connecting groove 257a in a circular arc shape of the cross-section perpendicular to the axial direction, resulting in a lower force concentration on the high-pressure fuel passing through the connecting groove. 257a flows.

[0106] The movable contact wall surface 257b , which defines the outer perimeter wall surface section 74 the floating plate 70 touched in a sliding manner, is located between the connecting grooves 257a , which border each other, in the circumferential direction of the cylinder 256 arranged. The movable contact wall surface 257b contacts or touches the outer perimeter wall surface section in this way 74 that the floating plate 70 through the movable contact wall surface 257b radially inwards with respect to the floating plate70 is held. Furthermore, according to the first embodiment, even between the movable contact wall surface 257b and the outer perimeter wall surface section 74 A small amount of fuel, such as from a very small fuel leak, flows.

[0107] Next, the operation will be used to open and close the valve section. 50 in the fuel injection device described above 200 regarding the Fig. 2, Fig. 6 and Fig. 7 described.

[0108] Before the outlet opening 54a with the feedback channel 14b through the operation of the pressure control valve 80 The plate anchoring section is connected or brought into contact with the plate anchoring section. 78 the floating plate 70 on the plate stop section 258a installed. When the operation or actuation of the pressure control valve 80 the outlet opening 54awith the feedback channel 14f connects (see Fig. 1) the fuel flows out of the counter-pressure chamber 53 through the outlet channel 54 This creates a phenomenon near the outlet opening. 54a such decompression that the floating plate 70 towards the opening wall surface 90 is pulled, thereby increasing the pressure area 73 on the opening wall surface 90 presses and this opens the inlet 52a blocked. Therefore, the jet needle opens. 60 , according to the first embodiment, when the pressure in the pressure control chamber 53 The pressure drops below the predetermined value, causing the valve section to close. 50 .

[0109] The floating plate 70 , which are located on the opening wall surface 90 When it is in contact with the opening wall surface, it presses against it. 90 , which opens the inlet 52a It is blocked. Due to the outflow through the connecting hole. 71flowing fuel enters the pressure control chamber 53 , in which the fuel flow from the inlet opening 52a interrupted, a rapid decompression of the pressure occurs. This decompression of the pressure in the pressure control chamber. 53 will the jet needle 60 in the direction of the pressure control chamber 53 pushed upwards so that the seat section 65 from the valve section 45 spaced apart, whereby the valve section 50 is held in the open position.

[0110] If the connection between the outlet opening 54a and the return channel 14f (see Fig. 1) by closing the pressure control valve 80 If interrupted, the floating plate 70 through the high-pressure fuel that passes through the intake port 52 It is inserted in this way in the direction of the jet needle. 60 pressed that the floating plate 70It begins to move. The spacing out or loosening of the floating plate. 70 from the opening wall surface 90 results in the opening of the intake channel 52 into the pressure control chamber 53 This results in high-pressure fuel entering the intake chamber. 53a introduced.

[0111] Then the water flows from the inlet channel. 52 into the entrance chamber 53a introduced fuel in the direction of the counter-pressure chamber 53b , through the four connecting grooves 257a , which are located on the interior wall surface section 256a of the cylinder 256 are arranged, and the four connecting holes 71 Through pressure recovery in the counter-pressure chamber 53b will the jet needle 60 towards the valve section 50 Pressed down. The jet needle 60 caused the seat section 65 such on the valve seat section 45is positioned so that the injection opening 44 is blocked. According to the second embodiment, the floating plate remains. 70 in contrast to the first embodiment, spaced apart or detached from the opening wall surface 90 , until the outlet opening 54a through the pressure control valve 80 with the feedback channel 14f (see Fig. 1) is associated with.

[0112] According to the second embodiment, the sufficient channel area to allow fuel flow is provided by the inlet channel. 53a to the counter-pressure chamber 53b through the connecting groove 257a This ensures that pressure recovery in the counter-pressure chamber is prevented. 53a through the floating plate 70 is interrupted.

[0113] Furthermore, the movable contact wall surface touches 257a the outer perimeter wall surface section 74 the floating plate70 so displaceable that the displacement axis of the floating plate 70 with respect to the axial direction of the cylinder 256 less likely to tilt. Therefore, the floating plate can 70 in the pressure control chamber 53 easily movable, making it possible to adjust the intake channel 52 into the pressure control chamber 53 to open quickly. This prevents the fuel flow into the pressure control chamber. 53 is guided through the floating plate 70 is restricted.

[0114] This allows the fuel to quickly enter the intake chamber. 53a be inserted and move smoothly into the counter-pressure chamber 53b This allows the time elapsed during the initial displacement of the jet needle to flow. 60 The time required for pressure recovery can be shortened. Furthermore, according to the fuel injection device... 200, the reaction capacity of the jet needle 60 The valve closure time can be improved.

[0115] Additionally, the floor section 257d the connecting groove 257 , on which the pressure of the pressurized fuel is applied, is configured in such a circular arc shape according to the second embodiment that the load is essentially not in the vicinity of the bottom section 257d where it is not compressed. Therefore, the resulting wear on the cylinder can occur. 256 by providing the connecting groove 257 This can be prevented. Furthermore, the depth of the connecting groove can be adjusted by distributing the loads. 257a in the radial direction of the cylinder 256 can be enlarged. Therefore, the width of the connecting groove can be increased. 257 The channel is tapered in the circumferential direction while ensuring sufficient channel area. This allows for a wider sliding contact wall surface.257b , which are located between the adjacent connecting grooves 257 The area is arranged in a circumferential direction and is therefore enlarged. This increases the surface area of ​​the outer circumferential wall surface section. 74 , which is the movable contact wall surface 257b touched, larger, thereby increasing the tilt or deflection of the floating plate 70 relative to the axial direction, this is less likely to occur. Therefore, the responsiveness of the nozzle needle can be... 60 at the valve closing time according to the fuel injection device 200 be improved, while the longevity of the fuel injection device 200 is guaranteed.

[0116] According to the second embodiment, the cylinder 256 an example of a cylindrical element described in the claims, and the inner wall surface section 256a an example of a cylindrical inner wall section described in the claims. (Third embodiment)

[0117] A third embodiment of the present invention, which is described in the Fig. 8 and Fig. Figure 9 shows another modified example of the first embodiment described above. A control body 340 a fuel injection device 300 According to the third embodiment, it has a cylinder 356 corresponding to the cylinder 56 (see Fig. 3) of the first embodiment. Furthermore, the fuel injection device includes 300 the third embodiment a floating plate 370 corresponding to the floating plate of the first embodiment. The construction of the fuel injection device is then described below. 300 according to the third embodiment with regard to the Fig. 8 and Fig. 9 described in detail.

[0118] An interior wall surface section 356a of the cylinder 356is connected by a connecting groove 357a , a movable contact wall surface 357b , a plate stopper section 358a and a sub-connecting groove 357g provided. According to the connecting groove. 257a (see Fig. 6) In the second embodiment, the connecting groove extends 357a along the axial direction of the cylinder 356 , thereby the entrance chamber 53a with the counter-pressure chamber 53b is connected. A pair of connecting grooves. 357a are on the interior wall surface section 356a provided. The connecting grooves 357a are 180° apart in the circumferential direction of the cylinder 356 Provided and spaced apart. Perpendicular to the axial direction of the cylinder in the radial direction of the cross-section. 356 a section of soil 357d the connecting grooves 357a a circular arc shape. The movable contact wall surface 357bis between the connecting groove 357a , which are adjacent to each other, arranged, and slidably touch an outer perimeter wall surface section 74 the floating plate 370 .

[0119] The plate stopper section 358a It has a stepped shape, which differs with respect to the inner wall surface section. 356a extends radially inwards, and is the pressure-bearing surface 377 , which is an end surface of the floating plate 370 on the side of the counter-pressure chamber 53b is, in contrast. The plate stopper section 358a is caused by the displacement of the floating plate 370 , which extend from the inlet channel 52 spaced apart, in such a way as to the pressure-bearing surface 377 the floating plate 370 in contact that the plate stopper section 358a the displacement of the floating plate 370 limited. The two sub-connecting grooves 357gare at the plate stopper section 358a planned.

[0120] The two sub-connecting grooves 357g are connected by the corresponding two connecting grooves 357a connected. Therefore, each connecting groove is 357a with the corresponding sub-connecting groove 357g intended to be the entrance chamber 53a with the counter-pressure chamber 53b to connect. The sub-connection grooves 357g are in the circumferential direction of the cylinder 356 The cylinders are positioned 180° apart. In the radial direction of the cross-section, they are perpendicular to the axial direction of the cylinder. 356 The sub-connecting groove 357g a circular arc shape. The sub-connecting groove 357g and the floor section 357b the connecting groove 357a They are coaxial to each other and have the same radius. A center or the middle of the circular arc shape of the sub-connecting groove. 357ais inside the plate stop section 358a in the radial direction of the cylinder 356 arranged. Thus, a channel area of ​​the sub-connection groove is formed. 357g in the direction of flow from the inlet chamber 53a to the counter-pressure chamber 53b larger upon reaching the downstream side.

[0121] As described above, by providing the plate stop section 358a with the sub-connecting groove 357g , even if the floating plate 370 and the plate stopper section 358 are connected to each other, the fuel between the intake chamber 53a and the counter-pressure chamber 53b flow. Thus, in the pressure-bearing surface 377 the floating plate 370 on a configuration corresponding to the radial groove 77a (see Fig. 3) be waived.

[0122] According to the third embodiment, the sub-connecting groove 357gin the plate stopper section 358a provided and with the connecting groove 357a integrated to the intake chamber 53a with the counter-pressure chamber 53b to connect in such a way that the fuel flow from the intake chamber 53a into the counter-pressure chamber 53b This ensures that pressure recovery in the counter-pressure chamber is prevented. 53b through contact between the pressure-receiving surface 377 and the plate stopper section 358 is interrupted. Thus, the responsiveness of the jet needle can be affected. 60 both at valve closing time and valve opening time according to the fuel injection device 300 can be improved.

[0123] Furthermore, the channel area of ​​the sub-connecting groove will be 357g According to the third embodiment, upon reaching the downstream side, the pressure is so great that the pressure of the fuel passing through the sub-connecting groove increases. 357gThe flow rate decreases upon reaching the downstream side of the fuel. This reduces the amount of fuel flowing through the connecting groove. 357a and the sub-connecting groove 357g flows, pulled in such a direction towards the downstream side that the fuel flows more easily from the intake chamber 53a into the counter-pressure chamber 53b can flow. This allows the printer recovery time to be shortened to such an extent that the responsiveness of the nozzle needle is significantly improved. 60 The valve closure time can be further improved.

[0124] According to the third embodiment, several connecting grooves can be used. 357a and several sub-connecting grooves 357g , which may also be more than two, are provided for, thereby increasing the channel area through which the fuel flows from the intake chamber 53a into the counter-pressure chamber 53bFlow can be ensured. Furthermore, the uniform spacing of the multiple connecting grooves can be achieved. 357a and several sub-connecting grooves 357g from each other in the circumferential direction of the cylinder 356 the fuel evenly around the floating plate 370 Flow. Thus, the inclination of the floating plate can be limited. As described above, the channel area is enlarged and the position of the floating plate is adjusted. 370 stabilized, so that pressure recovery in the counter-pressure chamber 53b It can be reached quickly and easily. This reduces the start-up time of the jet needle. 60 It is positioned forward, and the time variation can be small. Therefore, the responsiveness of the jet needle can be affected. 60 The valve closure time can be improved.

[0125] According to the third embodiment, the floating plate 370The radial groove for connection can be omitted, thus reducing the manufacturing costs of the floating plate. 370 can be reduced. Furthermore, the cross-section of the cylinder is... 356 the sub-connecting groove 357g and the connecting groove 357a Each is defined by its arcs, which are coaxial and have the same radius. Thus, the cutting processes can be used to form the joining groove. 357a and the sub-connecting groove 357g in the cylinder 356 The process is carried out simultaneously with the same tool. Therefore, the joining groove is formed simultaneously. 357a and the sub-connecting groove 357b in a cost reduction in the production of the cylinder 356 This allows the responsiveness of the nozzle element to be adjusted according to the fuel injection device. 300 Both valve closing time and valve opening time can be improved at lower costs.

[0126] According to the third embodiment, the control body 340 an example of a valve body described in the claims, the cylinder 356 an example of a cylindrical element described in the claims, the inner wall surface section 356a a cylindrical inner wall section as described in the claims, and the floating plate 370 an example of a control element described in the claims. (Fourth embodiment)

[0127] One in Fig. Figure 10, the fourth embodiment, shows a modification example of the second embodiment. A fuel injection device. 400 According to the fourth embodiment, it contains a cylinder. 456 corresponding to the cylinder 256 in the second embodiment. According to this, the design of the fuel injection device is... 400 according to the fourth embodiment regarding Fig. 10 and Fig. 6 described in detail.

[0128] An interior wall surface 456a of the cylinder 456 has a connecting wall section 457c and four connecting grooves 457a , essentially according to the connecting groove 257a the second embodiment, the connecting wall section 457c is between the connecting grooves 457a , which in the circumferential direction of the cylinder 456 adjacent to each other, arranged, and defines a connection gap 475 , which is the entrance chamber 53a with the counter-pressure chamber 53b connects, between the floating plate 70 and the outer perimeter wall surface section 74 .

[0129] According to the fourth embodiment, a sufficient channel area of ​​the passage, which leads to the inlet chamber, is provided. 53a with the counter-pressure chamber 53b connects, through the connecting groove 457aThis ensures the responsiveness of the jet needle. 60 The valve closure time can be improved.

[0130] Furthermore, the sufficient channel area is ensured by the connecting groove. 457a such that the channel area, which passes through the connection gap, is ensured 375 The depth of the connection gap is defined, but does not necessarily have to be increased. Therefore, the depth of the connection gap can be adjusted. 475 be so small that the inclination of the axis of the floating plate 70 can be limited. However, even if the channel area of ​​the connection gap results 375 small, the formation of the connection gap 375 in an enlargement of the entire channel area of ​​the passage, which is the inlet channel 53a with the counter-pressure chamber 53b connects. This increases the amount of fuel that enters the intake chamber. 53a into the counter-pressure chamber 53bThe flow rate increases. This shortens the printer recovery time to such an extent that the responsiveness of the nozzle needle is significantly improved. 60 The valve closure time can be further improved.

[0131] According to the fourth embodiment, the cylinder shows 456 an example of a cylindrical element described in the claims and the inner wall surface section 456a an example of a cylindrical inner wall section described in the claims. (Fifth embodiment)

[0132] One in Fig. Figure 11, the fifth embodiment, shows a further modification example of the second embodiment. In a fuel injection device 500 According to the fifth embodiment, a cylinder 556 corresponding to the cylinder 256 the second embodiment. According to this, the structure of the fuel injection device is as follows: 500according to the fifth embodiment with regard to the Fig. 6 and Fig. 11 described in detail.

[0133] In an inner wall surface section or interior wall surface section 556a a cylinder 556 are a connecting groove 557a and a movable contact wall surface 557b , which each form the connecting groove 257a and the movable contact wall surface 257b The second embodiment corresponds to the arrangement of four connecting grooves. According to the fifth embodiment, four connecting grooves are arranged. 557a , which is the entrance chamber 53a and the counter-pressure chamber 53b connect them evenly in the circumferential direction of the cylinder. 556 spaced apart. Each connecting groove 557a is spirally shaped around the central axis of the cylinder 556 wound or coiled along it. A movable contact surface. 557b is between the spiral connecting grooves 557aand the movable contacts of the outer perimeter wall surface section 74 the floating plate 70 planned.

[0134] According to the fifth embodiment described above, even if the connecting groove 557a It is spirally wound, it is possible that the inlet chamber 53a with the counter-pressure chamber 53b via the connecting groove 557a is connected in such a way that pressure recovery occurs in the counter-pressure chamber 53b can be reached quickly. Thus, even if the connecting groove 57a on an interior wall surface section 556a of the cylinder 556 is spirally shaped, the reactivity of the nozzle needle 60 The valve closure time can be improved.

[0135] According to the fifth embodiment, the cylinder 556an example of a cylindrical element described in the claims and the inner wall surface section 556a an example of a cylindrical inner wall section described in the claims. (Sixth and seventh embodiments)

[0136] A sixth embodiment and a seventh embodiment of the present invention, illustrated in the Fig. 12 and Fig. Figure 13 shows further modified examples of the second embodiment. Fuel injection devices 600 , 700 According to the sixth and seventh embodiments, cylinders contain 656 , 756 each corresponding to the cylinder 256 (see Fig. 6) of the second embodiment. On each of the inner wall surface sections. 656a , 756a the cylinder 656 , 756 Regarding the connecting grooves 657a , 757a knurling was carried out to create the inlet chamber350a with the counter-pressure chamber 53a to connect. For example, reference should be made to JISB-0951, which defines this type of knurling.

[0137] More precisely, as in Fig. 12 shows the knurling as the connecting groove. 657a The sixth embodiment is formed by equally spaced microgrooves that extend along the axial direction of the cylinder. 656 from each other in the circumferential direction of the cylinder 656 extend. The knurling in Fig. 12 corresponds to a parallel knurling as defined above in JISB-0951. The fuel entering the intake chamber 53a When introduced, it flows through the knurling and passes the floating plate. 70 in the displacement or axial direction, whereby the fuel enters the counter-pressure chamber 53b reached.

[0138] Furthermore, the knurling, as in Fig. 13, in the seventh embodiment by equally spaced microgrooves which spiral around the central axis of the cylinder 756 extend from each other in the circumferential direction of the cylinder 656 as a connecting groove 757a formed. By changing the direction of rotation of each spiral groove, the multiple microgrooves intersect, creating a diamond pattern. The knurling corresponds to a diamond knurling as defined in JISB-0951 described above. The one in the inlet chamber 53a The introduced fuel flows through the knurling and passes the floating plate. 70 in the axial direction of displacement, causing it to enter the counter-pressure chamber 53b flows.

[0139] As described above according to the sixth and seventh embodiments, the knurling can be described as the connecting grooves. 657a , 757amust be designed. Even the knurling described above allows fuel to flow from the intake port. 53a such a counter-pressure chamber 53b This ensures that pressure recovery occurs in the counter-pressure chamber. 53b can be achieved quickly. Therefore, the responsiveness of the jet needle can be increased. 60 The valve closure time can be improved. (Eighth embodiment)

[0140] One in Fig. Figure 14, the eighth embodiment, shows a further modification example of the first embodiment. In a fuel injection device 800 According to the eighth embodiment, a structure corresponding to the cylinder is used. 56 (see Fig. 3), which determines the radial direction of the pressure control chamber 53 The first embodiment is defined without specifying the nozzle body. Furthermore, the structure or design corresponds to the nozzle body. 41 (see Fig. 3) of the first embodiment a first nozzle body 841a and a second nozzle body 841b planned. This will be based on Fig. 14, the structure of the fuel injection device 800 as described in the eighth embodiment.

[0141] The first nozzle body 841a and the second nozzle body 841b are in this order from the tip of a control body 840 arranged. The injection opening 44 (see Fig. 2) is at one tip of the first nozzle body 841a trained. The pressure control chamber 53 is in the second nozzle body 841b arranged.

[0142] The first nozzle body 841a and the second nozzle body 841b include a nozzle needle housing section 843 and a feed channel 843a The nozzle needle housing section 843 and the feed channel 843acorrespond to the nozzle needle housing section 43 and the feed channel 43a of the first embodiment.

[0143] The nozzle needle housing section 843 is located in the radial central section of the first nozzle body. 841a and the second nozzle body 841b arranged and configured in the nozzle bodies 841a , 841b to be trained. On an interior wall surface section 856a on the side of the second nozzle body 841b are a control wall surface section 857 , a cylindrical displacement surface section 859 , a plate stopper section 858a and a needle stopper section 858b than the nozzle needle housing section 843 planned. The control wall surface section 857 , the cylindrical displacement surface section 859 , the plate stopper section 858a and the needle stopper section 858bare essentially similar to the corresponding components 57 , 59 , 58a , 58b (see Fig. 3), which are located in the interior wall surface section 56a of the cylinder 56 are designed in the first embodiment. The pressure control chamber 53 The eighth embodiment is characterized by the control wall surface section 854 of the second nozzle body 841b , the pressure-bearing surface 61 the jet needle 60 and the opening wall surface 90 defined.

[0144] A feed passage 843a is on an outer circumferential side of the pressure control chamber 53 arranged and configured, located in the first nozzle body 841a and the second nozzle body 841b to extend. The feed passage 843a extends along the axial direction of the control body 840 and is connected to the nozzle needle housing section 843Connected at one end in the axial direction. This allows the feed passage to pass through. 843a the pressurized fuel through the nozzle needle housing section 843 to.

[0145] In the control body 840 The pressure control chamber of the eighth embodiment described above is 53 and the feed passes 843a arranged. The pressure control chamber 53 restricts the movement of the jet needle 60 , and the feed passage 843a is a section through which the pressurized fuel enters the injection opening. 44 flows (see Fig. 2) According to the first embodiment, the pressure control chamber 53 through the cylinder 56 , which is located in the nozzle needle housing section 43 is held by the feed pass 43a (see Fig. 3) separated. In the eighth embodiment, the feed passage is 843ahowever, on the outer circumference side of the pressure control chamber 53 arranged in such a way that the pressure control chamber 53 through the second nozzle body 841b is defined in a state in which the pressure control chamber 53 from the feed passage 843a is separated.

[0146] As described above, the component that controls the pressure control chamber 53 defined, depending on the configuration of the fuel injection device, can be modified or replaced. However, regardless of the component that controls the pressure control chamber 53 defined if on the interior wall surface section 856a , which is the pressure control chamber 53 defined, a connecting groove 857a is designed and this allows the fuel flow from the intake chamber 53a into the counter-pressure chamber 53b flows, the pressure recovery in the counter-pressure chamber 53bThis can be achieved quickly. As a result, regardless of the fuel injection system configuration, the formation of the connecting groove occurs. 857a in improving the responsiveness of the nozzle needle 60 at the time of valve closure.

[0147] According to the eighth embodiment, a control body 840 an example of a valve body described in the claims, the first nozzle body 841a and the second nozzle body 841b Examples of a nozzle element described in the claims, and the inner wall surface section 856a an example of a cylindrical inner wall section described in the claims.

[0148] Although the present invention has been described together with the preferred embodiments with regard to the accompanying figures, it should be mentioned that the person skilled in the art can also deduce various changes and modifications from it.

[0149] In the embodiment described above, the configuration mentioned is one in which two or four connecting grooves are evenly spaced from one another in the circumferential direction of the cylinder on the inner wall surface section. However, the number, position, and configuration of the connecting groove are not limited to this. For example, only one connecting groove may also be provided on the inner wall surface section of the cylinder of the fuel injection device.

[0150] In the embodiment described above, either the movable contact wall surface or the connecting wall section is provided between the connecting grooves arranged on the inner wall surface section of the cylinder. However, both the movable contact wall surface and the connecting wall section can also be provided. This configuration limits the inclination or deflection of the floating plate and ensures sufficient fuel flow from the intake chamber. 53a into the counter-pressure chamber 53b .

[0151] In the third embodiment described above, the channel area of ​​the sub-connecting groove 357g configured to increase in size in the downstream direction. The configuration of the sub-connection groove. 357gHowever, this configuration of the third embodiment is not limited to this specific configuration. For example, the sub-connecting groove can extend along the radial direction and be configured as a homogeneous channel area. Furthermore, the number and position of the sub-connecting grooves are not limited to the configuration described above.

[0152] In the embodiment described above, the pressure control chamber is located in the axial direction of the fuel injection device. 53 in a section closer to the top, where the injection opening 44 is formed as on the base or end side, in which the base section 48cThe present invention is provided for. In a conventional fuel injection device, a configuration corresponding to the pressure control chamber for controlling the movement of the nozzle needle is arranged, however, at a location closer to the base or end side than to the tip side. The present invention can be applied to this conventional fuel injection device. More precisely, in the foregoing first to seventh embodiments, the pressure control chamber is formed by the several components that constitute the control body, and in particular by the cylinder. 53 defined. In the eighth embodiment, the pressure control chamber 53 basically through the second nozzle body 841b defined. The pressure control chamber 53 However, it can also be achieved by components that form the control body, and are not the cylinder or the nozzle body, such as components corresponding to the holder. 48in the embodiment described above.

[0153] According to the embodiment described above, the control section for opening and closing the pressure control valve is used. 80 , which controls the fuel pressure in the pressure control chamber 53 controls the structure to move the movable element through the electromagnetic force of the solenoid. 31 used. However, a control section can also be different from the solenoid. 31 , for example, a piezoelectric element can be used. In this case, too, the control section can be used to open and close a pressure control valve. 80 based on the control signal of the machine control or machine controller 17 can be controlled.

[0154] According to the embodiments described above, the present invention applies to a fuel injection device for a diesel engine. 20applied, the fuel goes directly into a combustion chamber 22 injects. However, the present invention is not limited to the diesel engine. 20 The invention is not limited to, but can also be used, for example, in an internal combustion engine, such as a gasoline engine and the like. Furthermore, the fuel injected by the fuel injection device is not limited to light oil or diesel, but can also be, for example, gasoline, LPG, and the like. Moreover, the present invention can also be applied to a fuel injection device that injects fuel not into a combustion chamber of an internal combustion engine, but into an external combustion engine. QUOTES INCLUDED IN THE DESCRIPTION

[0155] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0156] JP 2010-080838 A

[0001] JP 2010-270647 A

[0001] EP 1656498 A1

[0004] Cited non-patent literature

[0157] JISB-0951

[0030] JISB-0951

[0136] JISB-0951

[0137] JISB-0951

[0138]

Claims

[1] Fuel injection device with: a valve body in which a high-pressure fuel passage is provided, wherein the valve body has an injection opening at a tip from which the high-pressure fuel is injected into a combustion chamber of an internal combustion engine; a valve element which is movable in the valve body in its axial direction and opens or closes the injection port; a pressure control chamber which is provided in the valve body on one side opposite the injection opening with respect to the valve element, and which introduces the high-pressure fuel and controls the movement of the valve element by means of the fuel pressure; an inlet channel through which the high-pressure fuel is introduced into the pressure control chamber; an outlet channel through which the fuel is discharged from the pressure control chamber to an external low-pressure side; and a control element which is located in the valve body in its axial direction and opens or closes the inlet channel, wherein the valve body contains a cylindrical inner wall section that defines the pressure control chamber in its radial direction, and the cylindrical inner wall section contains a connecting groove which connects an inlet chamber, which is provided in the pressure control chamber on one side of the inlet channel with respect to the control element, with a back pressure chamber, which is provided in the pressure control chamber on one side of the valve element with respect to the control element. [2] Fuel injection device according to claim 1, wherein the cylindrical inner wall section is provided with a displaceable contact wall surface on an outer circumferential wall section about a displacement axis of the control element. [3] Fuel injection device according to claim 1 or 2, wherein the cylindrical inner wall section is provided with a connecting wall surface which defines a connecting gap between the cylindrical inner wall section and an outer circumferential wall about a displacement axis of the control element, and the connecting gap connects the inlet chamber to the back pressure chamber. [4] Fuel injection device according to any one of claims 1 to 3, wherein a bottom section of the connecting groove has an arc-shaped cross-section in the radial direction. [5] Fuel injection device according to one of claims 1 to 4, wherein several connecting grooves are arranged in the circumferential direction of the cylindrical inner wall section and are spaced apart from each other. [6] Fuel injection device according to claim 5, wherein the connecting grooves are spaced uniformly apart from each other in the circumferential direction. [7] Fuel injection device according to one of claims 1 to 6, wherein the valve body is provided with a restriction section which is opposite an end face of the control element on one side of the back pressure chamber, and the restriction section is provided with a sub-connecting groove which, together with the connecting groove, connects the inlet chamber to the back pressure chamber. [8] Fuel injection device according to claim 7, wherein the restriction section is configured in a stepped form extending towards the radial inside of the cylindrical inner wall section. [9] Fuel injection device according to claim 7 or 8, wherein the sub-connecting groove is configured to enlarge a channel area downstream in the direction of flow from the inlet chamber to the back pressure chamber. [10] Fuel injection device according to one of claims 7 to 9, wherein the cylindrical inner wall section contains several connecting grooves that are spaced apart from each other in the circumferential direction, the restriction section contains several sub-connecting grooves that are connected to the connecting grooves accordingly and are spaced apart from each other in the circumferential direction, and The connecting grooves and the sub-connecting grooves are evenly spaced from each other in the circumferential direction. [11] Fuel injection device according to one of claims 7 to 10, wherein a bottom section of the connecting groove is configured in a circular arc cross-section, and the sub-connecting groove is configured in a circular arc shape which is coaxial with the bottom section and has the same radius as the bottom section. [12] Fuel injection device according to claim 11, wherein the center of the circular arc shape of the sub-connecting groove is located in the radial center of the confinement section. [13] Fuel injection device according to claim 6, wherein the connecting grooves are configured by knurling provided in the cylindrical inner wall section. [14] Fuel injection device according to one of claims 1 to 13, wherein the connecting groove extends along the axial direction. [15] Fuel injection device according to one of claims 1 to 14, wherein the connecting groove is spirally wound along the central axis of the cylindrical inner wall section. [16] Fuel injection device according to any one of claims 1 to 15, wherein the valve body is provided with a feed passage through which the high-pressure fuel is fed into the injection opening, which is located at the tip end, and the valve body has a cylindrical element that is held in the feed passage, defines the cylindrical inner wall section on an inner circumferential side and separates the pressure control chamber from the feed passage. [17] Fuel injection device according to any one of claims 1 to 15, wherein the valve body has a nozzle element that forms the tip end in which the injection opening is provided, and The nozzle element defines the pressure control chamber through the cylindrical inner wall section, and a feed passage is positioned on an outer circumferential side of the pressure control chamber to feed the high-pressure fuel into the injection port.