JP6408278B2 - Screw-in connector for directing fuel to the injection nozzle - Google Patents

Description

  The present invention relates to a screw-type connector for guiding fuel to an injection nozzle of an internal combustion engine. The screw-type connector includes a pressure connector and a pressure screw, and can be fixed to the internal combustion engine using a holding body. The pressure connector can be fixed against rotation with respect to the holding body.

  An injection nozzle or an injector for dispensing fuel is generally fixed in a cylinder head of an internal combustion engine using a holding body. In this case, the fuel is supplied through a screw-type connector connected to the fuel conduit. The fuel conduit may be a common rail conduit. Therefore, the screw-type connector also serves to supply fuel to the injection nozzle.

  The screw-type connector is fixed in the holding body by a male screw formed on the pressure screw. That is, the sealing surface formed on the pressure connector is fixed so as to contact the corresponding sealing surface in the holding body, thereby preventing the fuel from flowing out of the region of the sealing surface.

  In the conventional screw-type connector derived from the applicant, during the screw connector movement of the pressure connector, a relative movement occurs between the sealing surface of the pressure connector and the sealing surface of the holding body, and the sealing surface is at risk of damage. .

  In order to avoid this, in a further conventional screw-type connector derived from the applicant, a pressure ring is provided in the end region of the pressure connector, so that even in a configuration consisting of two parts, a pressure connector and a pressure screw. When the pressure screw is tightened to provide an axial force to produce a sealing effect, the pressure connector is no longer in relative rotational motion when the pressure connector seal surface is supported on the holder seal surface. It is already possible not to be exposed.

  In this second known embodiment, an anti-rotation device is attached to the pressure connector, and the anti-rotation device protects the pressure connector from rotating relative to the holding body. This is necessary because after installing the screw connector, the fuel conduit must be secured to the remote end of the screw connector using a nut. This leads to rotation of the screw-in connector, and the reaction moment caused thereby is introduced into the cylinder head through the anti-rotation device rather than being supported in the area of the sealing surface.

  However, it has become clear in practice that a certain anti-rotation device is not always installed during the installation of the screw-in connector, and therefore damage can still occur in the area of the sealing surface, In some cases, expensive repairs are required.

  Under these circumstances, in order to eliminate the described drawbacks, the present invention makes it a challenge to configure a screw-type connector so that errors in installation can no longer occur.

  The present invention has the features described in claim 1 in order to solve the problem. Advantageous embodiments thereof are described in the other claims.

  The present invention creates a threaded connector for directing fuel to an injection nozzle of an internal combustion engine. The screw-in type connector has a pressure connector and a pressure screw, and can be fixed to the internal combustion engine using a holding body. The pressure connector can be fixed against rotation with respect to the holding body. The pressure connector has an end having an outer contour that is different from a circular shape.

  Therefore, the pressure connector of the screw-in type connector according to the present invention has an end portion having a characteristic outer contour, and the outer contour is introduced into the shape of the holding body and the recessed portion formed in a surface complementary manner. It is possible that the holding body can again be fixed to an internal combustion engine, for example a cylinder head of the internal combustion engine. That is, when the screw-in type connector is attached to the internal combustion engine according to the configuration of the present invention, a pressure connector having an end formed so as not to rotate with the holding body is introduced into the recess of the holding body. It will be necessary. Mounting such that the end of the pressure connector is not introduced into a complementary recess formed in the holding body is almost impossible with the configuration according to the present invention.

  The screw-in connector is attached to the internal combustion engine, so that the assembler must attach the end to the recess in the holder so that the pressure connector end is received in position in the recess in the holder If this is the case, the arrangement according to the invention makes other positions impossible.

  The attachment is performed so that the pressure connector penetrates the pressure screw and contacts the holding body through the pressure screw. That is, before the male screw formed on the pressure screw is engaged with the female screw formed on the holding body, the attachment is performed so that the end portion of the pressure connector is engaged with the concave portion of the holding body. As a result, when the installer tightens the pressure screw against the holding body, the pressure connector is necessarily fixed in position and is in contact with the holding body so that it does not rotate. Relative rotation between the sealing surface formed on the body can no longer occur. Similarly, when the fuel conduit is attached to the pressure screw, relative movement can no longer occur in the region of the pressure connector and the sealing surface of the retainer.

  According to a preferred embodiment, the end of the pressure connector is formed integrally with the pressure connector, so that the non-circular outer contour is arranged in direct contact with the pressure connector. However, the present invention also provides that the pressure connector is provided with a separate pressure body at its end, the pressure body having a non-circular outer contour. In this way, the pressure connector can be provided with a male screw in the end region, and the pressure body can be provided with a female screw, whereby the pressure body can be releasably fixed to the pressure connector. Yes, it is possible to fit the pressure connector in the recess of the holding body together with the pressure body arranged there. By tightening the pressure screw again, the axial force required to act on the sealing surface necessary to produce a sealing effect is realized without the relative movement between the sealing surfaces being caused by the rotational movement of the pressure screw.

  In a further configuration of the invention, it is provided that the pressure connector is provided with a circumferential collar in the end region, so that the end of the pressure screw can abut against the circumferential collar. Thus, tightening the pressure screw allows the axial force necessary to provide a sealing effect to be applied to the pressure connector. For this purpose, it is possible to provide a circumferential collar at the end of the pressure screw as well, and the region between the circumferential collar of the pressure screw and the circumferential collar of the pressure connector contains, for example, a solid lubricant. It is possible to introduce an insert in the form of a strip of material, which strip receives a relative rotational movement between both circumferential collars. Thereby, the screw-type connector can be repeatedly released and screwed again without damaging the screw-type connector.

  According to a further configuration of the invention, it is provided that the pressure screw has a sleeve-like elongate body with an inner recess, the body being formed for receiving a pressure connector. . In this way, the screw-in connector, together with both the pressure connector and the pressure screw, can be introduced into the cylinder head of the internal combustion engine through the corresponding receiving opening, and the pressure connector is fitted into the recess of the holding body.

  In order to secure the screw-type connector to the holding body, in a further configuration of the invention it is provided that the pressure screw is provided with a male screw at its end. At the end opposite to the axial direction, the pressure screw is provided with a longitudinal opening extending along a partial region of the longitudinal extension of the pressure screw, and the longitudinal opening penetrates the pressure screw. It has a larger diameter than the inner recess and is used to receive the pressure connector.

  The longitudinal opening is used to receive a retaining ring or spring washer, by means of which both members, the pressure connector and the pressure screw, are irreversibly in contact with each other, but axially with respect to each other. Being arranged to be movable and rotatable relative to each other, the pressure connector can be fitted into the recess of the holding body using a pressure screw. For this purpose, the pressure connector and the pressure screw are provided with corresponding markings, which make the orientation of the end of the pressure connector relative to the recess of the holder visible to the assembler. .

  A further configuration of the invention provides that the axial longitudinal extension of the male thread of the pressure screw is smaller or the same as the axial longitudinal extension of the end of the pressure connector. With this arrangement, the pressure connector is its male thread, before the pressure connector can be engaged with the complementary female thread of the holding body to form an axial force in the region of the sealing surface. It is achieved that at the characteristic end it must be received in a recess in the holding body. Thereby, a configuration in which an operation error at the time of attachment is eliminated is created. Because it is only possible to place the screw-in connector in contact with the internal combustion engine if the pressure connector is mounted in the correct position at its characteristic end, which prevents the sealing surface from rotating. It is.

  In a further configuration of the invention, the pressure screw has an engagement portion that is different from a circular shape on the outer periphery so that the engagement portion engages with an anti-rotation device that can be releasably secured to the internal combustion engine. It is also defined that it is formed. It is thereby possible to fix the pressure screw against rotation to the cylinder head after its installation, which determines the axial force in the area of the sealing surface between the pressure connector and the holding body. And, when securing the fuel conduit to the pressure screw using a nut, the torque applied to the pressure screw may have the advantage that it could otherwise lead to changes in the axial force applied to the sealing surface Yes. That is, the screw connector according to the present invention allows both the pressure connector and the pressure screw to be arranged in contact with the cylinder head so as not to rotate.

  In order to allow the fuel conduit to be releasably secured to the screw connector, according to a further configuration of the invention, the pressure screw is opposite to the end provided for placement at the end of the pressure connector. It is defined in the end region on the side that it is configured to engage a nut, whereby the fuel conduit can be releasably secured to the pressure screw in a fluid-conducting and fluid-tight manner. . Thus, fuel can be directed in the direction of the injection nozzle through a screw-in connector.

  Finally, the present invention provides a receiving space for leakage fluid between the nut and the pressure screw, the receiving space being in fluid conductive connection with a spill conduit for discharging the leakage fluid. It is also characterized by being. Thereby, fuel which can possibly flow out to the sealing surface can be guided through the screw-in connector towards the receiving space, through which the fuel is opened in an opening formed in the nut. And a spill conduit for controlled discharge.

  Finally, according to a further configuration of the invention, the pressure connector and / or the end of the pressure body and the engagement part of the pressure screw have a configuration similar to a polygon or a key or a polygon with at least three corners. It is also stipulated. Accordingly, it becomes possible to fix the pressure connector to the holding body so as not to rotate by using the concave portion formed in a shape and surface complementary in the holding body. Neither the rotational movement nor the application of torque to the pressure screw during the installation of the nut during the fixing of the fuel conduit is exposed to relative rotational movement.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The following figure is shown.

1 is a longitudinal sectional view of an embodiment of a screw-type connector according to the present invention. It is sectional drawing of the area | region between the characteristic edge part of a pressure connector, and a holding body. It is a top view of a part of a screw-in type connector arranged on a cylinder head for explaining a rotation prevention device for a pressure screw.

  FIG. 1 shows a longitudinal sectional view of one embodiment of a screw-type connector 1 according to the present invention.

  The screw connector 1 is composed of a pressure screw 2 so as to be composed of two parts. The pressure screw has a sleeve-like elongated main body 3 with an inner recess 4. A pressure connector 5 having an end 6 passes through the inner recess 4 and the end 6 has an outer contour different from the circle shown in detail in FIG. 2, the outer contour being the illustrated embodiment. Is formed to be similar to a key.

  Here, the outer contour formed so as to resemble the key has a length extending in the axial longitudinal direction of the pressure connector 5, which is denoted by “a” in the illustrated embodiment. Has been. The end 6 is disposed in a recess 7 formed in a shape and surface complementary to the outer contour of the end 6. This will be described in detail with reference to FIG.

  The pressure connector 5 has a circumferential collar 8 in the region of the end portion 6, and the circumferential collar 8 is provided with a circumferential collar 9 of the pressure screw 2. Since an axial force can be applied through the screwing movement of the holding body 11 of the pressure screw 2 to the female screw 10, the seal surface 12 formed at the end 6 of the pressure connector 5 is held by a predetermined contact pressure. It abuts against the sealing surface 13 of the body 11 and therefore prevents the fuel from flowing out of the sealing surface region.

  The length of the portion 14 provided with the male screw of the pressure screw 2 marked “b” is smaller than the length of the characteristic end 6 of the pressure connector 5 marked “a”. Thereby, the end 6 of the pressure connector 5 is reliably disposed in the recess 7 of the holding body 11 before the first inter-thread spacing of the male screw 15 of the pressure screw 2 engages the female screw of the holding body 11. Can be done. Accordingly, erroneous fixing of the screw-in connector 1 in the region of the cylinder head 16 of the internal combustion engine not shown in detail is reliably avoided.

  The screw-type connector 1 generally has an elongated structure and passes through an inner recess 17 disposed in the cylinder head 16. The pressure screw 2 has an outer contour different from a circle in the region of its longitudinal extension, which is accessible from the outside when the screw-type connector 1 is placed on the cylinder head 16, and is evident from FIG. As can be seen, in the illustrated embodiment, the outer contour is designed as a hexagon 18. In this way, by means of the hexagon 18, a screwing movement onto the pressure screw 2 can also be caused simultaneously using a tool not shown in detail.

  In the end region opposite to the male screw 15, a further male screw 19 is provided on the pressure screw 2, and a nut 20 having a complementary female screw 21 can be fixed to the male screw 19. .

  Through the fastening of the nut 20, the fuel conduit 22 can be fluidly connected with the screw-in connector 1. The nut 20 has a recess 23, in which fuel that has flowed out from the region of the seal surfaces 12, 13 can be collected. The fuel is contained in the pressure connector 5 and the pressure screw 2. It can move in the direction of the recess 23 along the formed inner recess.

  By making the screw-in connector 1 into a double wall structure in this way, it is possible to control and discharge the fuel leaking from the area of the seal surface, and it is provided in the nut 20 in the area of the recess 23. It is also possible to return the fuel, for example to the fuel collection container, through an opening, not shown in detail, through which a spill conduit can be connected.

  The pressure screw 2 has a longitudinal opening 25 extending along a partial region of the longitudinal extension of the pressure screw 2 at an end 24 opposite to the male screw 15, and along the opening, The retaining ring 26 shown only schematically in FIG. 1 can be displaced. The retaining ring 26 ensures the fixation of the pressure connector 5 to the pressure screw 2 so that both members can be rotated relative to each other and can be axially displaced relative to each other, You can't leave one another. Thereby, both members of the pressure screw 2 and the pressure connector 5 of the screw-type connector 1 can be attached only when they are attached together, and as a result, the pressure connector 5 is again arranged so as not to rotate on the holding body 11. Therefore, the relative movement between the sealing surfaces 12, 13 after the pressure connector 5 is installed in the correct position is automatically prevented. Therefore, the sealing surface is protected from damage.

  This is because, in the embodiment shown in FIG. 2, the end 6, which is designed to be similar to the key of the pressure connector 5, is configured to be complementary to the end 6 in shape and surface. This is made possible by being arranged in the recess 7 so as not to rotate.

  After the application of torque to the pressure screw 2, which is performed to bring the surface pressure to the area of the sealing surfaces 12, 13, the pressure screw with the anti-rotation device 26 shown in detail in FIG. It can be fixed so as not to.

  For this purpose, the anti-rotation device has a holding body 27, which can be fixed to the cylinder head 11 by means of a screw 29 arranged in the slot 28. At this time, the long hole 28 is used so that the double-tooth profile 31 of the anti-rotation device 26 arranged in the recess 30 can adjust the angle with respect to the hexagonal profile of the pressure screw 2.

  The screw-type connector 1 is fluid-tightly sealed against the surroundings in the region of the anti-rotation device 26 by means of a seal 32 shown in detail in FIG. And the area between the nut 20 is sealed. A further seal 34 in the region between the nut 20 and the fuel conduit 22 prevents fuel from flowing out of the fuel supply region formed by the screw-in connector 1.

  With the screw-in connector 1 according to the present invention, the end 6 is introduced into the recess 7 of the holding body 11 and at the same time, the damage of the sealing surfaces 12 and 13 due to the relative rotational movement of the pressure connector 5 with respect to the holding body 11 is eliminated. . As a result, errors during installation are unlikely.

  For features of the invention that have not been described in detail individually, reference is made to the corresponding drawings.

DESCRIPTION OF SYMBOLS 1 Screw-in type connector 2 Pressure screw 3 Main-body part 4 Inner recessed part 5 Pressure connector 6 End part 7 Recessed part 8 Circumferential collar 9 Circumferential collar 10 Screw 11 Holder 12 Sealing surface 13 Sealing surface 14 Part 15 Male screw 16 Cylinder head 17 Inside Recess 18 Hexagon 19 Male screw 20 Nut 21 Female screw 22 Fuel conduit 23 Recess, receiving space 24 End 25 Long opening 26 Anti-rotation device 27 Holding body 28 Long hole 29 Screw 30 Recess 31 Double tooth profile 32 Seal 33 Seal 34 Seal

Claims (10)

A screw-in connector (1) for guiding fuel to an injection nozzle of an internal combustion engine, the screw-in connector (1) having a pressure connector (5) and a pressure screw (2), 11) a screw-type connector (1) that can be fixed to the internal combustion engine by 11) and the pressure connector (5) can be fixed so as not to rotate with respect to the holding body (11);
The pressure connector (5) has an end (6) with an outer contour different from a circle,
The pressure screw (2) is provided with a male screw (15) at its end (14), and an axially long extension of the pressure screw (2) at the end opposite to the axial direction. A longitudinal opening (25) extending along the partial region is provided, the longitudinal opening having a larger diameter than the inner recess (4) passing through the pressure screw (2). A screw-type connector (1) characterized by that.   The screw-type connector (1) according to claim 1, wherein the end (6) is configured to complement the shape and surface of the recess (7) provided in the holding body (11). 1).   Screw-type connector according to claim 1 or 2, characterized in that the pressure connector (5) is provided with a separate pressure body at the end (6) having an outer contour different from a circle. (1).   The pressure connector (5) is provided with a circumferential collar (8) in the region of the end (6), and the end of the pressure screw (2) contacts the circumferential collar. Screw-in connector (1) according to any one of the preceding claims, characterized in that it is possible.   The pressure screw (2) comprises a sleeve-like elongated body (3) having an inner recess (4), the inner recess being formed for receiving the pressure connector (5). The screw-type connector (1) according to any one of claims 1 to 4. The axial longitudinal extension of the male screw (15) of the pressure screw (2) is smaller than or the same as the axial longitudinal extension of the end (6) of the pressure connector (5). The screw-type connector (1) according to any one of claims 1 to 5 , characterized in that. The pressure screw (2) has an engagement portion different from a circular shape on the outer periphery, and the engagement portion engages with an anti-rotation device (26) that can be releasably fixed to the internal combustion engine. The screw-type connector (1) according to any one of claims 1 to 6 , wherein the screw-type connector (1) is formed as described above. The pressure screw (2) engages with a nut (20) in an end region opposite to the end provided for placement at the end (6) of the pressure connector (5). is configured to, by the nut, the fuel conduit (22), fluid conductivity and fluid tight manner, claim 1, wherein the may be releasably secured to the pressure screws (2) 7 Screw-in connector (1) as described in any one. A receiving space (23) for leakage fluid is formed between the nut (20) and the pressure screw (2), the receiving space being a spill conduit and fluid for discharging the leakage fluid. Screw-in connector (1) according to claim 8 , characterized in that it is hermetically connected. Engaging portion of the pressure connector (2) the end of and / or the pressure body (6) and said pressure screw (2) have a polygonal configuration with a polygonal or key, or at least three corners to any one of claims 1 9, characterized in that are listed in the screw-connector (1).

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