JP6068516B2 - Fuel injection device - Google Patents

Description

  The present invention relates to a fuel injection device comprising a plurality of members for an internal combustion engine.

  Internal combustion engines known from practice, for example marine diesel engines, have a plurality of cylinders, each of which is provided with at least one fuel injector, whereby individual cylinders are arranged. Supply fuel to the cylinder. In many cases, such a fuel injection device is composed of a plurality of members or components continuously attached in the longitudinal direction, and the plurality of members or components are (for example, the length of the members or components). They must be installed or fixed to each other in a specific arrangement (with respect to the axis and the rotational position of the member or component).

  In a fuel injection device known from practice, this alignment of a plurality of components in this manner is performed using so-called alignment pins that engage the alignment pin holes of the components. For example, Patent Document 1 discloses a fuel injection device composed of such a plurality of members. In the fuel injection device, a nozzle structure is aligned with a nozzle holder by an alignment pin.

  However, the alignment pin has the following disadvantages. That is, the alignment pins are easily damaged or sheared due to mechanical overloads during installation or removal of the fuel injector, so that the alignment components that are typically broken in the individual components are usually With regard to removing the pins, laborious repair work is required.

  Further disadvantages of the alignment pins are as follows. That is, since the alignment pin hole for receiving the alignment pin is usually provided in the sealing surface between the components, the alignment pin protrudes from the sealing surface after the alignment pin is attached, In order to rework the sealing surface (for example, lapping), first, it is necessary to remove the alignment pin by taking time and effort.

German Patent Application No. 2309134

  It is an object of the present invention to provide a fuel injection device comprising a plurality of members, in which the components of the fuel device are aligned with each other in a manner that is easier and easier to maintain.

  The above object is achieved by a fuel injection device according to claim 1. Further configurations of the invention are defined in the dependent claims.

  According to the present invention, a fuel injection device includes, as a plurality of components coupled to each other, an injection nozzle for injecting fuel, a switching valve for controlling fuel injection, the injection nozzle and the switching valve, The injection nozzle has a predetermined nozzle outer contour at the longitudinal end portion of the injection nozzle, and the switching valve is a longitudinal portion of the switching valve. Having a predetermined valve outer contour at a directional end portion, the connecting sleeve having a predetermined sleeve inner contour, from the first longitudinal end of the connecting sleeve to the sleeve inner contour, The injection nozzles are fitted in a shape connection by the nozzle external contour of the injection nozzles, whereby the injection nozzles are installed in a predetermined arrangement with respect to the connection sleeve, From the second longitudinal end of the connecting sleeve, the switching valve is fitted into the sleeve inner contour in a shape connection by the valve outer contour of the switching valve, so that the switching valve is connected to the connecting sleeve. Are installed in a predetermined arrangement.

  In other words, the valve outer contour is conformally adapted to the sleeve inner contour, whereby a first shape connective coupling of the shaft and hub is created as an alignment means, the nozzle outer contour Is conformally adapted to the inner contour of the sleeve, whereby a second shape connective coupling of the shaft and hub is created as an alignment means. Therefore, the valve outer contour and the nozzle outer contour are each formed complementary to the sleeve inner contour.

  Assembling the individual components of the fuel injector in the axial direction usually involves, for example, one or more connecting nuts that engage the corresponding ring collar and male threads of the component, as seen in the prior art. Surely done.

  By fitting the nozzle outer contour and the valve outer contour to the sleeve inner contour in a shape-connective manner as in the present invention, the components of the fuel injector are aligned with each other in a particularly simple and easy to maintain manner. Yes.

  When the components of the fuel injection device are to be removed and possibly reworked, the shaft and hub connection can be removed by pulling the individual components from the connecting sleeve after removing the axial coupling. All you have to do is release it.

  The fuel injection device according to the invention, having a shaft-hub connection realized via a polygonal cross-section, is clearly more resistant to mechanical loads, so that it is positioned during installation and removal. The risk of damaging the mating means is reduced.

  Furthermore, the implementation of the components as described above makes it possible to transmit a much larger tightening torque, for example using a single or a plurality of connecting nuts, taking into account that the injection pressure is constantly increased. More and more is necessary to achieve sufficient sealing.

  Preferably, the connecting sleeve is sized or configured such that the connecting sleeve forms the weakest member of the component. Thereby, in the event of a mechanical overload, only the connecting sleeve is destroyed or damaged, so that only the connecting sleeve can be replaced in a simple manner and without using various instruments.

  According to one embodiment of the invention, the sleeve inner contour is in the longitudinal direction of the sleeve inner contour adapted to the valve outer contour at the longitudinal end portion of the sleeve inner contour adapted to the nozzle outer contour. It may have a different inner diameter than that at the end portion. This configuration of the present invention has the advantage that the components of the injection nozzle and the switching valve can be dimensioned in consideration of space requirements and fitted into a common connection sleeve.

  According to a further embodiment of the invention, the nozzle outer contour and the valve outer contour are fitted into the sleeve inner contour in a shape-connecting manner, whereby the injection nozzle and the switching valve are respectively the longitudinal lengths of the injection nozzle and the switching valve. With respect to the axis and the rotational position, they are aligned in a defined state, particularly with respect to the connecting sleeve which is a connecting sleeve for centering.

  In other words, the longitudinal axis of the injection nozzle and the switching valve is a position at which the injection nozzle and the switching valve rotate around the longitudinal axis with respect to the longitudinal axis of the connecting sleeve and together with the longitudinal axis of the connecting sleeve by the coupling of the shaft and the hub. And with each other at the same time.

  According to a further embodiment of the invention, the sleeve inner contour has a polygonal shape. Such a polygonal shape is created or present in the nozzle outer contour and in the valve outer contour in a complementary manner because the polygonal shape is, for example, elliptical turning or elliptical polishing, or It can be manufactured by milling.

  Preferably, the polygonal shape is formed at least in the form of a triangle (for example with a uniform thickness P3G as defined in DIN32711) and in particular hexagonal and heptagonal.

  According to one embodiment of the invention, the sleeve inner contour is formed symmetrically with respect to the longitudinal axis of the connecting sleeve.

  In the above case, preferably, a first fitting of the protrusion and the recess is provided between the sleeve inner contour and the nozzle outer contour, and the first fitting of the protrusion and the recess is the connection of the injection nozzle. Defines the only possible rotational alignment for the sleeve, and a second fitting of the protrusion and recess is provided between the sleeve inner contour and the valve outer contour, the second of the protrusion and recess The second fit defines the only possible rotational alignment of the switching valve with respect to the connecting sleeve.

  In this way, a unique rotational alignment is performed among the injection nozzle, the switching valve, and the connecting sleeve.

  According to an alternative embodiment of the invention, the sleeve inner contour is formed asymmetrically with respect to the longitudinal axis of the connecting sleeve.

  In the above case, the polygonal shape having a plurality of sides preferably has a length at least one side different from the other sides of the polygonal shape. More preferably, the polygonal shape includes a first side having a length smaller than the other side of the polygonal shape and a second side having a length larger than the other side of the polygonal shape. Have.

  In this way, also in this case, a unique rotational alignment is performed among the injection nozzle, the switching valve and the connecting sleeve.

  According to a further embodiment of the invention, a fuel orifice is fitted in the sleeve inner contour between the injection nozzle and the switching valve in a shape-connecting manner. In other words, the orifice outer contour is conformally adapted to the sleeve inner contour, or is formed complementary to the sleeve inner contour, thereby providing a third shape connective coupling of the shaft and hub. Has been produced.

  When the orifice outer contour and the sleeve inner contour are formed symmetrically with respect to the longitudinal axis between the orifice outer contour and the sleeve inner contour, a fitting between the protrusion and the recess may be provided. If the sleeve inner contour is formed asymmetrically with respect to the longitudinal axis, the orifice outer contour need only be complementary to the sleeve inner contour.

  Thereby, also with respect to the fuel orifice, a unique rotational alignment with respect to the other components of the fuel injection device is realized.

  All shaft-hub couplings or shape-connective fittings are preferably implemented as clearance fits or intermediate fits with a slight clearance.

  The invention also provides an internal combustion engine, in particular a marine diesel engine, having a fuel injection device according to one, a plurality or all of the above-described embodiments of the invention in all possible combinations.

  In summary, according to an embodiment of the present invention, an injection nozzle of a fuel injection device having a switching valve and, in some cases, a fuel orifice provided in the switching valve are centered and uniquely positioned. (I.e., fixed alignment) is performed, and the alignment is realized using a polygonal cross-sectional shape.

  The centering sleeve or connecting sleeve as a member for connecting the injection nozzle of the fuel injection device having the switching valve, the switching valve, and possibly the fuel orifice, eliminates the need for the alignment pin. Thereby, the number of additional members required for alignment is reduced from four to one.

  If the alignment pin is damaged or sheared during removal or installation and the alignment pin is broken or sheared, the troublesome repair to the switching valve or injection nozzle when removing the broken alignment pin Will do. On the other hand, if a mechanical overload is applied to the connecting sleeve, it can be replaced without the use of further tools.

  Polygonal cross-sections as axisymmetric geometries with mating projections and recesses (such as structures with alignment pins and corresponding alignment pin recesses that traverse the longitudinal direction of the connecting sleeve) Alternatively, by implementing an asymmetric geometry, it is possible to uniquely position or align the injection nozzle, the fuel orifice, and the switching valve.

  Prior art alignment pins were often overloaded in practice. If the spray nozzles are the same size, greater torque is transmitted through the polygonal coupling than through the alignment pins used so far in the prior art.

  The alignment (preferably including centering) of the injection nozzle with respect to the fuel orifice and the switching valve can be achieved by, for example, combining a shaft with a hub, a polygonal shaft such as a polygonal cross-sectional shape P3G (DIN32711) This is done using a hub connection. At least two corners of a triangular polygonal shape, by changing the radius slightly different, or by creating an axisymmetric cross-sectional shape with a centering pin, or at least one shortening, for example By creating an asymmetric cross-sectional shape such as a hexagon having a defined side L-Y and at least one extended side L + X (preferably X = Y), for example, the length of the component of the fuel injector Inadvertent mis-installation, as possible by twisting 120 degrees around the axis, is unlikely. This makes it possible to omit the alignment pin in its original form.

  It is obvious that the present invention extends to embodiments that are not given by the combination of features obtained from the explicit citation of the claims, whereby the features disclosed in the present invention are technically meaningful. As long as they are arbitrarily combined.

  The present invention will be described below based on preferred embodiments with reference to the accompanying drawings.

1 is an exploded perspective view of a fuel injection device according to an embodiment of the present invention. FIG. 6 is a perspective view of a connecting sleeve of a fuel supply device according to a further embodiment of the present invention. It is a figure which shows the cross section or end surface of the connection sleeve of FIG. FIG. 4 shows a longitudinal section of the connecting sleeve of FIG. 2 taken along line AA of FIG. 3.

  FIG. 1 is an exploded view of a fuel injection device 1 of an internal combustion engine (not fully shown) formed as a marine diesel engine in the figure, constructed according to the first embodiment of the present invention. Is shown in perspective.

  The fuel injection device 1 has an injection nozzle 10 for injecting fuel (here, diesel fuel), a switching valve 20 for controlling (allowing / blocking) fuel injection, an injection nozzle 10 and a switching valve 20. And a connecting sleeve or centering sleeve 30 provided between them.

  The injection nozzle 10 has a predetermined nozzle outer contour 12 at a longitudinal end portion 11 facing the connecting sleeve 30 of the injection nozzle, and the switching valve 20 is a longitudinal end facing the connecting sleeve 30 of the switching valve. The part 21 has a predetermined valve outer contour 22.

  The connection sleeve 30 has a predetermined sleeve inner contour 33 on the connection sleeve side, and the injection nozzle 10 is connected to the injection nozzle 10 from the first longitudinal end portion 31 of the connection sleeve 30. The nozzle outer contour 12 is inserted in a shape-connected manner, whereby the injection nozzle 10 is installed in a predetermined arrangement with respect to the connecting sleeve 30.

  In the sleeve inner contour 33, the switching valve 20 is also fitted in a shape-connecting manner from the second longitudinal end 32 of the connecting sleeve 30 by the valve outer contour 22 of the switching valve, whereby the switching valve 20 is The connecting sleeve 30 is installed in a predetermined arrangement.

  In other words, the valve outer contour 22 is conformally adapted to the sleeve inner contour 33, whereby a first shape connective coupling of the shaft and hub is created as an alignment means. Is conformally adapted to the sleeve inner contour 33, whereby a second shape connective coupling of the shaft and hub is created as an alignment means.

  Accordingly, each of the valve outer contour 12 and the nozzle outer contour 22 is complementarily formed with respect to the sleeve inner contour 33.

  Further, a fuel orifice 40 is inserted into the sleeve inner contour 33 between the injection nozzle 10 and the switching valve 20 in a shape-connected manner with the fuel orifice 40 being installed in a predetermined arrangement with respect to the connecting sleeve 30.

  In other words, the orifice outer contour 41 of the fuel orifice 40 is conformally adapted to the sleeve inner contour 33 or is formed complementary to the sleeve inner contour 33 so that the shaft and hub third This shape-connective connection is created as an alignment means.

  All shaft-hub couplings or shape-connective fittings are preferably implemented as clearance fits or intermediate fits with a slight clearance.

  As can be seen from FIG. 1, the injection nozzle 10 has a longitudinal axis L1, the switching valve 20 has a longitudinal axis L2, the connecting sleeve 30 has a longitudinal axis L3, and the fuel orifice 40 has a longitudinal axis L4. Have.

  According to the present invention, the nozzle outer contour 12, the valve outer contour 22, and the orifice outer contour 41 are fitted into the sleeve inner contour 33 in a shape-connected manner, whereby the injection nozzle 10, the switching valve 20, the fuel Orifice 40 refers to the injection nozzle, switching valve and fuel orifice longitudinal axis L1, L2 or L4, and the rotational position of the injection nozzle, switching valve and fuel orifice about each longitudinal axis L1, L2 or L4, respectively. It is aligned in a defined state with respect to the connecting sleeve 30. In other words, the longitudinal axes L1, L2 or L4 of the injection nozzle 10, the switching valve 20 and the fuel orifice 40 are mutually connected to and along with the longitudinal axis L3 of the connecting sleeve 30 by the coupling of the shaft and the hub. The injection nozzle, the switching valve and the fuel orifice are aligned or centered with each other at and together with the position rotating about the longitudinal axis L1, L2 or L4.

  In order to achieve alignment, each of the valve outer contour 12, the nozzle outer contour 22, and the orifice outer contour 41 has a polygonal shape, and the sleeve inner contour 33 corresponds to the outer contour (valve outer contour 12). And a polygonal shape complementary to the nozzle outer contour 22 and the orifice outer contour 41). The inner polygonal shape and the outer polygonal shape can be produced, for example, by elliptical turning or elliptical polishing or milling.

  According to the invention, the individual polygonal shapes of the components of the fuel injection device 1 are at least triangular, and according to FIG.

  Combining the individual components of the fuel injection device 1 in the axial direction (longitudinal) is usually, for example, of the components (such as the ring collar 13 of the injection nozzle 10), as can be seen in the prior art. This is ensured by one or more connecting nuts (not shown) that engage the corresponding ring collars and male threads (not shown).

  Although not shown in FIG. 1, according to one embodiment of the present invention, the sleeve inner contour 33 is at the longitudinal end portion 31.1 of the sleeve inner contour adapted to the nozzle outer contour 12. The sleeve inner contour adapted to the valve outer contour 22 may have a different inner diameter than that at the longitudinal end portion 32.1. This configuration of the present invention has the advantage that the components of the injection nozzle 10 and the switching valve 20 can be dimensioned in consideration of space requirements and can be fitted into the common connecting sleeve 30.

  As can be seen from FIG. 1, the individual polygonal shapes (valve outer contour 12, nozzle outer contour 22, sleeve inner contour 33, and orifice outer contour 41) of the components of the fuel injection device 1 are It is formed asymmetrically with respect to the longitudinal axis L1, L2, L3 or L4, thereby ensuring a unique rotational alignment between the injection nozzle 10, the switching valve 20, the fuel orifice 40 and the connecting sleeve 30. Yes. In other words, each component of the fuel injection device 1 can be inserted into the connecting sleeve 30 only in a predetermined rotary alignment.

  Specifically, each polygonal shape includes a plurality of sides S, S ′, S ″, an angle E connecting the sides, and at least one side having a length different from the other sides S of the polygonal shape. S ′ and S ″ (three sides in FIG. 1).

  According to FIG. 1, each polygonal shape has three sides S ′, S ″ having a smaller length than the other sides S of the polygonal shape, and has a relatively small length. One of the sides S ′, S ″ that is formed is one of the sides S ′, S ″ that is formed with a relatively small length of the polygonal shape. It has a length smaller than the other side S ′.

  FIGS. 2 to 4 show a fuel supply device 1a (completely shown) for an internal combustion engine (not fully shown) formed as a marine diesel engine constructed according to a second embodiment of the invention. (Not shown) is shown.

  The fuel supply device 1a according to the second embodiment of the present invention is formed in the same manner as the fuel supply device 1 according to the first embodiment of the present invention except for some differences. Accordingly, in the following, only the differences will be shown, and the same or similar components as in FIG. 1 are represented by the same or similar reference numerals, and the reference numerals of the modified components are represented by lowercase letters. The alphabet “a” is followed. As is apparent from FIGS. 2 to 4, the individual polygonal shapes of the components of the fuel supply device 1a are at least triangular, and according to the figure, they are particularly hexagonal.

  The individual polygonal shapes (valve outer contour, nozzle outer contour, sleeve inner contour 33a and orifice outer contour) of the components of the fuel injection device 1a are again formed asymmetrically with respect to the longitudinal axis of the polygonal shape. This guarantees an unambiguous rotational alignment between the injection nozzle, the switching valve, the fuel orifice and the connecting sleeve 30a. Thereby, each component of the fuel injection device 1a can be inserted into the connecting sleeve 30a only in a predetermined rotary alignment. Specifically, the individual polygonal shapes of the components of the fuel injection device 1a are different from the plurality of sides S, S ′, S ″, the angle E connecting the sides, and the other sides S of the polygonal shape. It has at least one side S ′, S ″ (two sides in FIGS. 2 to 4) having a length.

  According to FIGS. 2 to 4, the individual polygonal shapes of the components of the fuel injection device 1 a are the first side and have a length (L−Y) smaller than the other side S of the polygonal shape. And a second side having a length (L + X) greater than the other side S of the polygonal shape (having a length dimension L). It has a second side S ′, preferably the length dimension X is the same as the length dimension Y.

  According to modifications not shown in the drawings of the first and second embodiments of the present invention, individual polygonal shapes (valve external contour, nozzle external contour, sleeve internal contour, and orifice external (Contour) may be formed symmetrically with respect to the longitudinal axis of the polygonal shape.

  In this case, a first fitting of the projection and the recess is provided between the sleeve inner contour and the nozzle outer contour, and the first fitting of the projection and the recess is the only one with respect to the connecting sleeve of the injection nozzle. Stipulates possible rotational alignments. In addition, a second fitting of the protrusion and the recess is provided between the sleeve inner contour and the valve outer contour, and the second fitting of the protrusion and the recess is the only one for the switching sleeve of the switching valve. Specifies possible rotational alignment. Finally, there is also a protrusion and recess fit between the orifice outer contour and the sleeve inner contour, which is the only possible connection of the fuel orifice to the connecting sleeve. Specifies rotary alignment.

  The alignment of the individual protrusions and recesses is, for example, an alignment pin recess that extends transversely to the longitudinal axis (injection nozzle, switching valve or fuel orifice) in the individual external contour according to the depth And an alignment pin that is transverse to the longitudinal axis, protrudes radially inward from the inner contour of the sleeve, and engages with the alignment pin recess. Preferably, the alignment pin recess has an open end in the longitudinal direction of the individual components, through which the alignment pin allows the component to be connected to the connecting sleeve. Upon insertion, it can be inserted into the individual alignment pin recess.

DESCRIPTION OF SYMBOLS 1 Fuel injection apparatus 1a Fuel injection apparatus 10 Injection nozzle 11 Longitudinal end part 12 Nozzle external outline 13 Ring collar 20 Switching valve 21 Longitudinal end part 22 Valve external outline 30 Connection sleeve 30a Connection sleeve 31 Longitudinal end 31. DESCRIPTION OF SYMBOLS 1 Longitudinal edge part 31.1a Longitudinal edge part 32 Longitudinal edge part 32.1 Longitudinal edge part 32.1a Longitudinal edge part 33 Sleeve internal outline 33a Sleeve internal outline 40 Fuel orifice 41 Orifice external outline L1, L2 Longitudinal axis L3, L4 Longitudinal axis L Length dimension X, Y Length dimension S, S ', S "Side E Angle

Claims (7)

An injection nozzle (10) for injecting fuel, a switching valve (20) for controlling fuel injection, and a connection provided between the injection nozzle (10) and the switching valve (20) A fuel injection device (1; 1a) having a sleeve (30; 30a),
The injection nozzle (10) has a predetermined nozzle outer contour (12) at a longitudinal end portion (11) of the injection nozzle, and the switching valve (20) is a longitudinal end portion of the switching valve. (21) having a predetermined valve outer contour (22);
The connecting sleeve (30; 30a) has a predetermined sleeve inner contour (33; 33a), and the sleeve inner contour has a first longitudinal end (31) of the connecting sleeve (30; 30a). ), The injection nozzle (10) is fitted in a shape-connected manner by the nozzle external contour (12) of the injection nozzle, whereby the injection nozzle (10) is in relation to the connecting sleeve (30; 30a) It is installed in a predetermined arrangement,
From the second longitudinal end (32) of the coupling sleeve (30; 30a), the switching valve (20) is fitted into the sleeve inner contour in a shape-connected manner by the valve outer contour (22) of the switching valve. The switching valve (20) is thereby installed in a predetermined arrangement with respect to the connecting sleeve (30; 30a) ,
The sleeve inner contour (33; 33a) has a polygonal shape, and the sleeve inner contour (33; 33a) is formed asymmetrically with respect to the longitudinal axis (L3) of the connecting sleeve (30; 30a). Injection device.   The nozzle outer contour (12) and the valve outer contour (22) are fitted into the sleeve inner contour (33; 33a) in a shape-connected manner, whereby the injection nozzle (10) and the switching valve ( 20) is a state defined with respect to the connection sleeve (30; 30a) with respect to the longitudinal axis (L1, L2) of the injection nozzle and the switching valve and the rotational position of the injection nozzle and the switching valve, respectively. 2. The fuel injection device (1; 1a) according to claim 1, which is aligned at It said polygonal shape, at least triangular, is formed in a hexagon or heptagon, fuel injection device according to claim 1 (1; 1a). A first fitting of a protrusion and a recess is provided between the sleeve inner contour (33; 33a) and the nozzle outer contour (12). Defines the only possible rotational alignment of the injection nozzle (10) with respect to the connecting sleeve (30; 30a), between the sleeve inner contour (33; 33a) and the valve outer contour (22) It provided second mating projections and recesses, the second mating of the protrusion and the recess, the coupling sleeve of the switching valve (20); only possible for (30 30a) 2. The fuel injection device (1; 1a) according to claim 1 , wherein the rotary alignment is defined. The polygonal shape includes a plurality of sides (S, S ′, S ″) and at least one side (S ′, S ″) having a different length from the other sides (S) of the polygonal shape. the has a fuel injection device according to claim 1 (1; 1a). The polygonal shape is a first side (S ″) having a length smaller than the other side (S) of the polygonal shape and a second side ( a S '), and a, a second side having a length greater than the other side of the polygonal shape (S), the fuel injection device according to claim 5 ( 1a). Said sleeve inner contour; between (33 33a) in the switching valve the injection nozzle (10) (20), the fuel orifice (40) is shaped connectively fitted, any one of claims 1 to 6 The fuel injection device (1; 1a) according to one item.

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